diff --git a/.github/workflows/pull-request.yml b/.github/workflows/pull-request.yml
index ef506506..1ecbe9ad 100644
--- a/.github/workflows/pull-request.yml
+++ b/.github/workflows/pull-request.yml
@@ -199,7 +199,7 @@ jobs:
         timeout-minutes: 30
         uses: ./.github/actions/setup
       - name: Build and test
-        timeout-minutes: 25
+        timeout-minutes: 30
         run: |
           ./gradlew test
       - name: Collect Artifacts
@@ -292,7 +292,7 @@ jobs:
         timeout-minutes: 30
         uses: ./.github/actions/setup
       - name: Build and test
-        timeout-minutes: 25
+        timeout-minutes: 30
         env:
           ORG_GRADLE_PROJECT_ZCASH_EMULATOR_WTF_API_KEY: ${{ secrets.EMULATOR_WTF_API_KEY }}
         run: |
@@ -336,7 +336,7 @@ jobs:
         run: |
           keytool -genkey -v -keystore $SIGNING_KEY_PATH -keypass android -storepass android -alias androiddebugkey -keyalg RSA -keysize 2048 -validity 100000 -dname "CN=, OU=, O=Test, L=, S=, C=" -noprompt
       - name: Build
-        timeout-minutes: 30
+        timeout-minutes: 35
         env:
           ORG_GRADLE_PROJECT_ZCASH_RELEASE_KEYSTORE_PATH: ${{ format('{0}/release.jks', env.home) }}
           ORG_GRADLE_PROJECT_ZCASH_RELEASE_KEYSTORE_PASSWORD: android
@@ -395,7 +395,7 @@ jobs:
         with:
           name: Demo app release binaries
       - name: Robo test
-        timeout-minutes: 15
+        timeout-minutes: 20
         env:
           # Path depends on `release_build` job, plus path of `Download a single artifact` step
           BINARIES_ZIP_PATH: binaries.zip
diff --git a/.gitignore b/.gitignore
index 90af866e..fc0bfdd3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -51,6 +51,7 @@ captures/
 .idea/workspace.xml
 .idea/protoeditor.xml
 .idea/appInsightsSettings.xml
+.idea/migrations.xml
 *.iml
 
 # Keystore files
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6e770d4f..799d7831 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,8 +1,60 @@
-# Change Log
+# Changelog
+All notable changes to this library will be documented in this file.
 
-## 1.21.0-beta01
-Note: This is the last _1.x_ version release. The upcoming version _2.0_ brings the **Spend-before-Sync** feature, 
-which speeds up discovering the wallet's spendable balance.  
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this library adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [2.0.0-rc.1] - 2023-09-12
+
+### Notable Changes
+
+- `CompactBlockProcessor` now processes compact blocks from the lightwalletd
+  server using the **Spend-before-Sync** algorithm, which allows scanning of
+  wallet blocks to be performed in arbitrary order and optimized to make it
+  possible to spend received notes without waiting for synchronization to be
+  complete. This feature shortens the time until a wallet's spendable balance
+  can be used.
+- The block synchronization mechanism is additionally about one-third faster
+  thanks to an optimized `CompactBlockProcessor.SYNC_BATCH_SIZE` (issue **#1206**).
+
+### Removed
+- `CompactBlockProcessor.ProcessorInfo.lastSyncHeight` no longer had a
+  well-defined meaning after implementation of the **SpendBeforeSync**
+  synchronization algorithm and has been removed.
+  `CompactBlockProcessor.ProcessorInfo.overallSyncRange` provides related
+  information.
+- `CompactBlockProcessor.ProcessorInfo.isSyncing`. Use `Synchronizer.status` instead.
+- `CompactBlockProcessor.ProcessorInfo.syncProgress`. Use `Synchronizer.progress` instead.
+- `alsoClearBlockCache` parameter from rewind functions of `Synchronizer` and
+  `CompactBlockProcessor`, as it has no effect on the current behaviour of
+  these functions.
+- Internally, we removed access to the shared block table from the Kotlin
+  layer, which resulted in eliminating these APIs:
+  - `SdkSynchronizer.findBlockHash()`
+  - `SdkSynchronizer.findBlockHashAsHex()`
+
+### Changed
+- `CompactBlockProcessor.quickRewind()` and `CompactBlockProcessor.rewindToNearestHeight()`
+  now might fail due to internal changes in getting scanned height. Thus, these
+  functions now return `Boolean` results.
+- `Synchronizer.new()` and `PersistableWallet` APIs require a new
+  `walletInitMode` parameter of type `WalletInitMode`, which describes wallet
+  initialization mode. See related function and sealed class documentation.
+
+### Fixed
+- `Synchronizer.getMemos()` now correctly returns a flow of strings for sent
+  and received transactions. Issue **#1154**.
+- `CompactBlockProcessor` now triggers transaction polling while block
+  synchronization is in progress as expected. Clients will be notified shortly
+  after every new transaction is discovered via `Synchronizer.transactions`
+  API. Issue **#1170**.
+
+## [1.21.0-beta01]
+
+Note: This is the last _1.x_ version release. The upcoming version _2.0_ brings the **Spend-before-Sync** feature,
+which speeds up discovering the wallet's spendable balance.
 
 ### Changed
 - Updated dependencies:
@@ -18,7 +70,7 @@ which speeds up discovering the wallet's spendable balance.
 
 ## 1.20.0-beta01
 - The SDK internally migrated from `BackendExt` rust backend extension functions to more type-safe `TypesafeBackend`.
-- `Synchronizer.getMemos()` now internally handles expected `RuntimeException` from the rust layer and transforms it 
+- `Synchronizer.getMemos()` now internally handles expected `RuntimeException` from the rust layer and transforms it
   in an empty string.
 
 ## 1.19.0-beta01
@@ -28,16 +80,16 @@ which speeds up discovering the wallet's spendable balance.
 ### Fixed
 - `TransactionOverview` object returned with `SdkSynchronizer.transactions` now contains a correct `TransactionState.
   Pending` in case of the transaction is mined,but not fully confirmed.
-- When the SDK internally works with a recently created transaction there was a moment in which could the transaction 
+- When the SDK internally works with a recently created transaction there was a moment in which could the transaction
   causes the SDK to crash, because of its invalid mined height. Fixed now.
 
 ## 1.18.0-beta01
-- Synchronizer's functions `getUnifiedAddress`, `getSaplingAddress`, `getTransparentAddress`, and `refreshUtxos` now 
-  do not provide `Account.DEFAULT` value for the account argument. As accounts are not fully supported by the SDK 
-  yet, the caller should explicitly set Account.DEFAULT as the account argument to keep the same behavior.   
+- Synchronizer's functions `getUnifiedAddress`, `getSaplingAddress`, `getTransparentAddress`, and `refreshUtxos` now
+  do not provide `Account.DEFAULT` value for the account argument. As accounts are not fully supported by the SDK
+  yet, the caller should explicitly set Account.DEFAULT as the account argument to keep the same behavior.
 - Gradle 8.1.1
 - AGP 8.0.2
- 
+
 ## 1.17.0-beta01
 - Transparent fund balances are now displayed almost immediately
 - Synchronization of shielded balances and transaction history is about 30% faster
@@ -46,7 +98,7 @@ which speeds up discovering the wallet's spendable balance.
 - `Synchronizer.progress` now returns `Flow<PercentDecimal>` instead of `Flow<Int>`. PercentDecimal is a type-safe model. Use `PercentDecimal.toPercentage()` to get a number within 0-100% scale.
 - `Synchronizer.clearedTransactions` has been renamed to `Synchronizer.transactions` and includes sent, received, and pending transactions.  Synchronizer APIs for listing sent, received, and pending transactions have been removed.  Clients can determine whether a transaction is sent, received, or pending by filtering the `TransactionOverview` objects returned by `Synchronizer.transactions`
 - `Synchronizer.send()` and `shieldFunds()` are now `suspend` functions with `Long` return values representing the ID of the newly created transaction.  Errors are reported by thrown exceptions.
- - `DerivationTool` is now an interface, rather than an `object`, which makes it easier to inject alternative implementations into tests.  To adapt to the new API, replace calls to `DerivationTool.methodName()` with `DerivationTool.getInstance().methodName()`.  
+ - `DerivationTool` is now an interface, rather than an `object`, which makes it easier to inject alternative implementations into tests.  To adapt to the new API, replace calls to `DerivationTool.methodName()` with `DerivationTool.getInstance().methodName()`.
  - `DerivationTool` methods are no longer suspending, which should make it easier to call them in various situations.  Obtaining a `DerivationTool` instance via `DerivationTool.getInstance()` frontloads the need for a suspending call.
  - `DerivationTool.deriveUnifiedFullViewingKeys()` no longer has a default argument for `numberOfAccounts`.  Clients should now pass `DerivationTool.DEFAULT_NUMBER_OF_ACCOUNTS` as the value. Note that the SDK does not currently have proper support for multiple accounts.
  - The SDK's internals for connecting with librustzcash have been refactored to a separate Gradle module `backend-lib` (and therefore a separate artifact) which is a transitive dependency of the Zcash Android SDK.  SDK consumers that use Gradle dependency locks may notice this difference, but otherwise it should be mostly an invisible change.
@@ -59,7 +111,7 @@ which speeds up discovering the wallet's spendable balance.
 ## 1.15.0-beta01
 ### Changed
 - A new package `sdk-incubator-lib` is now available as a public API.  This package contains experimental APIs that may be promoted to the SDK in the future.  The APIs in this package are not guaranteed to be stable, and may change at any time.
-- `Synchronizer.refreshUtxos` now takes `Account` type as first parameter instead of transparent address of type 
+- `Synchronizer.refreshUtxos` now takes `Account` type as first parameter instead of transparent address of type
     `String`, and thus it downloads all UTXOs for the given account addresses. The Account object provides a default `0` index Account with `Account.DEFAULT`.
 
 ## 1.14.0-beta01
@@ -68,11 +120,11 @@ which speeds up discovering the wallet's spendable balance.
 
 ## 1.13.0-beta01
 ### Changed
-- The SDK's internal networking has been refactored to a separate Gradle module `lightwallet-client-lib` (and 
+- The SDK's internal networking has been refactored to a separate Gradle module `lightwallet-client-lib` (and
   therefore a separate artifact) which is a transitive dependency of the Zcash Android SDK.
     - The `z.cash.ecc.android.sdk.model.LightWalletEndpoint` class has been moved to `co.electriccoin.lightwallet.client.model.LightWalletEndpoint`
     - The new networking module now provides a `LightWalletClient` for asynchronous calls.
-    - Most unary calls respond with the new `Response` class and its subclasses. Streaming calls will be updated 
+    - Most unary calls respond with the new `Response` class and its subclasses. Streaming calls will be updated
       with the Response class later.
     - SDK clients should avoid using generated GRPC objects, as these are an internal implementation detail and are in process of being removed from the public API.  Any clients using GRPC objects will find these have been repackaged from `cash.z.wallet.sdk.rpc` to `cash.z.wallet.sdk.internal.rpc` to signal they are not a public API.
 
@@ -129,7 +181,7 @@ which speeds up discovering the wallet's spendable balance.
   - `Synchronizer.sendToAddress()` and `Synchronizer.shieldFunds()` return flows that can now be collected multiple times.  Prior versions of the SDK had a bug that could submit transactions multiple times if the flow was collected more than once.
 - Updated dependencies:
   - Kotlin 1.7.21
-  - AndroidX  
+  - AndroidX
   - etc.
 - Updated checkpoints
 
@@ -154,14 +206,14 @@ which speeds up discovering the wallet's spendable balance.
   - `DerivationTool.deriveTransparentSecretKey` (use `DerivationTool.deriveUnifiedSpendingKey` instead).
   - `DerivationTool.deriveShieldedAddress`
   - `DerivationTool.deriveUnifiedViewingKeys` (use `DerivationTool.deriveUnifiedFullViewingKey` instead)
-  - `DerivationTool.validateUnifiedViewingKey` 
+  - `DerivationTool.validateUnifiedViewingKey`
 
 ## Version 1.9.0-beta05
 - The minimum version of Android supported is now API 21
 - Fixed R8/ProGuard consumer rule, which eliminates a runtime crash for minified apps
 
 ## Version 1.9.0-beta04
-- The SDK now stores sapling param files in `no_backup/co.electricoin.zcash` folder instead of the `cache/params` 
+- The SDK now stores sapling param files in `no_backup/co.electricoin.zcash` folder instead of the `cache/params`
   folder. Besides that, `SaplingParamTool` also does validation of downloaded sapling param file hash and size.
 **No action required from client app**.
 
@@ -177,7 +229,7 @@ which speeds up discovering the wallet's spendable balance.
  - Updated checkpoints
 
 ## Version 1.8.0-beta01
-- Enabled automated unit tests run on the CI server 
+- Enabled automated unit tests run on the CI server
 - Added `BlockHeight` typesafe object to represent block heights
 - Significantly reduced memory usage, fixing potential OutOfMemoryError during block download
 - Kotlin 1.7.10
diff --git a/LICENSE b/LICENSE
index 51ce0d39..4e6dfe52 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017-2021 Electric Coin Company
+Copyright (c) 2017-2023 Electric Coin Company
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index 355902db..f02c0803 100644
--- a/README.md
+++ b/README.md
@@ -53,3 +53,9 @@ Note that we aim for the main branch of this repository to be stable and releasa
 1. Intel-based machines may have trouble building in Android Studio.  The workaround is to add the following line to `~/.gradle/gradle.properties`: `ZCASH_IS_DEPENDENCY_LOCKING_ENABLED=false`
 1. During builds, a warning will be printed that says "Unable to detect AGP versions for included builds. All projects in the build should use the same AGP version."  This can be safely ignored.  The version under build-conventions is the same as the version used elsewhere in the application.
 1. Android Studio will warn about the Gradle checksum.  This is a [known issue](https://github.com/gradle/gradle/issues/9361) and can be safely ignored.
+
+## Unstable Features
+### Spend-before-Sync compact blocks synchronization algorithm
+`CompactBlockProcessor` now processes compact blocks from the lightwalletd server in non-linear order with the 
+**Spend-before-Sync** algorithm. This feature speeds up discovering the wallet's spendable balance. Please note that 
+this new block synchronization algorithm is still under development.
diff --git a/backend-lib/Cargo.lock b/backend-lib/Cargo.lock
index 98e9eebe..96697766 100644
--- a/backend-lib/Cargo.lock
+++ b/backend-lib/Cargo.lock
@@ -4,9 +4,9 @@ version = 3
 
 [[package]]
 name = "addr2line"
-version = "0.19.0"
+version = "0.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a76fd60b23679b7d19bd066031410fb7e458ccc5e958eb5c325888ce4baedc97"
+checksum = "8a30b2e23b9e17a9f90641c7ab1549cd9b44f296d3ccbf309d2863cfe398a0cb"
 dependencies = [
  "gimli",
 ]
@@ -24,14 +24,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d122413f284cf2d62fb1b7db97e02edb8cda96d769b16e443a4f6195e35662b0"
 dependencies = [
  "crypto-common",
- "generic-array 0.14.7",
+ "generic-array",
 ]
 
 [[package]]
 name = "aes"
-version = "0.8.2"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "433cfd6710c9986c576a25ca913c39d66a6474107b406f34f91d4a8923395241"
+checksum = "ac1f845298e95f983ff1944b728ae08b8cebab80d684f0a832ed0fc74dfa27e2"
 dependencies = [
  "cfg-if",
  "cipher",
@@ -40,20 +40,35 @@ dependencies = [
 
 [[package]]
 name = "ahash"
-version = "0.7.6"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fcb51a0695d8f838b1ee009b3fbf66bda078cd64590202a864a8f3e8c4315c47"
+checksum = "2c99f64d1e06488f620f932677e24bc6e2897582980441ae90a671415bd7ec2f"
 dependencies = [
- "getrandom",
+ "cfg-if",
  "once_cell",
  "version_check",
 ]
 
 [[package]]
-name = "anyhow"
-version = "1.0.71"
+name = "aho-corasick"
+version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c7d0618f0e0b7e8ff11427422b64564d5fb0be1940354bfe2e0529b18a9d9b8"
+checksum = "0c378d78423fdad8089616f827526ee33c19f2fddbd5de1629152c9593ba4783"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "allocator-api2"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0942ffc6dcaadf03badf6e6a2d0228460359d5e34b57ccdc720b7382dfbd5ec5"
+
+[[package]]
+name = "anyhow"
+version = "1.0.75"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4668cab20f66d8d020e1fbc0ebe47217433c1b6c8f2040faf858554e394ace6"
 
 [[package]]
 name = "arrayref"
@@ -63,9 +78,9 @@ checksum = "6b4930d2cb77ce62f89ee5d5289b4ac049559b1c45539271f5ed4fdc7db34545"
 
 [[package]]
 name = "arrayvec"
-version = "0.7.2"
+version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8da52d66c7071e2e3fa2a1e5c6d088fec47b593032b254f5e980de8ea54454d6"
+checksum = "96d30a06541fbafbc7f82ed10c06164cfbd2c401138f6addd8404629c4b16711"
 
 [[package]]
 name = "autocfg"
@@ -75,9 +90,9 @@ checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
 [[package]]
 name = "backtrace"
-version = "0.3.67"
+version = "0.3.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "233d376d6d185f2a3093e58f283f60f880315b6c60075b01f36b3b85154564ca"
+checksum = "2089b7e3f35b9dd2d0ed921ead4f6d318c27680d4a5bd167b3ee120edb105837"
 dependencies = [
  "addr2line",
  "cc",
@@ -88,23 +103,17 @@ dependencies = [
  "rustc-demangle",
 ]
 
-[[package]]
-name = "base-x"
-version = "0.2.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4cbbc9d0964165b47557570cce6c952866c2678457aca742aafc9fb771d30270"
-
 [[package]]
 name = "base58"
-version = "0.1.0"
+version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5024ee8015f02155eee35c711107ddd9a9bf3cb689cf2a9089c97e79b6e1ae83"
+checksum = "6107fe1be6682a68940da878d9e9f5e90ca5745b3dec9fd1bb393c8777d4f581"
 
 [[package]]
 name = "base64"
-version = "0.21.0"
+version = "0.21.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a4a4ddaa51a5bc52a6948f74c06d20aaaddb71924eab79b8c97a8c556e942d6a"
+checksum = "414dcefbc63d77c526a76b3afcf6fbb9b5e2791c19c3aa2297733208750c6e53"
 
 [[package]]
 name = "base64ct"
@@ -148,7 +157,7 @@ dependencies = [
  "hmac",
  "pbkdf2",
  "rand",
- "sha2 0.10.6",
+ "sha2",
  "unicode-normalization",
  "zeroize",
 ]
@@ -159,6 +168,12 @@ version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
+[[package]]
+name = "bitflags"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b4682ae6287fcf752ecaabbfcc7b6f9b72aa33933dc23a554d853aea8eea8635"
+
 [[package]]
 name = "bitvec"
 version = "1.0.1"
@@ -193,43 +208,13 @@ dependencies = [
  "constant_time_eq",
 ]
 
-[[package]]
-name = "block-buffer"
-version = "0.7.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c0940dc441f31689269e10ac70eb1002a3a1d3ad1390e030043662eb7fe4688b"
-dependencies = [
- "block-padding",
- "byte-tools",
- "byteorder",
- "generic-array 0.12.4",
-]
-
-[[package]]
-name = "block-buffer"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4152116fd6e9dadb291ae18fc1ec3575ed6d84c29642d97890f4b4a3417297e4"
-dependencies = [
- "generic-array 0.14.7",
-]
-
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3078c7629b62d3f0439517fa394996acacc5cbc91c5a20d8c658e77abd503a71"
 dependencies = [
- "generic-array 0.14.7",
-]
-
-[[package]]
-name = "block-padding"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa79dedbb091f449f1f39e53edf88d5dbe95f895dae6135a8d7b881fb5af73f5"
-dependencies = [
- "byte-tools",
+ "generic-array",
 ]
 
 [[package]]
@@ -247,24 +232,19 @@ dependencies = [
 
 [[package]]
 name = "bs58"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "771fe0050b883fcc3ea2359b1a96bcfbc090b7116eae7c3c512c7a083fdf23d3"
+checksum = "f5353f36341f7451062466f0b755b96ac3a9547e4d7f6b70d603fc721a7d7896"
 dependencies = [
- "sha2 0.9.9",
+ "sha2",
+ "tinyvec",
 ]
 
 [[package]]
 name = "bumpalo"
-version = "3.12.1"
+version = "3.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9b1ce199063694f33ffb7dd4e0ee620741495c32833cde5aa08f02a0bf96f0c8"
-
-[[package]]
-name = "byte-tools"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3b5ca7a04898ad4bcd41c90c5285445ff5b791899bb1b0abdd2a2aa791211d7"
+checksum = "a3e2c3daef883ecc1b5d58c15adae93470a91d425f3532ba1695849656af3fc1"
 
 [[package]]
 name = "byteorder"
@@ -274,9 +254,9 @@ checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
 [[package]]
 name = "bytes"
-version = "1.4.0"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "89b2fd2a0dcf38d7971e2194b6b6eebab45ae01067456a7fd93d5547a61b70be"
+checksum = "a2bd12c1caf447e69cd4528f47f94d203fd2582878ecb9e9465484c4148a8223"
 
 [[package]]
 name = "cbc"
@@ -289,9 +269,12 @@ dependencies = [
 
 [[package]]
 name = "cc"
-version = "1.0.79"
+version = "1.0.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "50d30906286121d95be3d479533b458f87493b30a4b5f79a607db8f5d11aa91f"
+checksum = "f1174fb0b6ec23863f8b971027804a42614e347eafb0a95bf0b12cdae21fc4d0"
+dependencies = [
+ "libc",
+]
 
 [[package]]
 name = "cesu8"
@@ -350,23 +333,17 @@ dependencies = [
  "memchr",
 ]
 
-[[package]]
-name = "const_fn"
-version = "0.4.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fbdcdcb6d86f71c5e97409ad45898af11cbc995b4ee8112d59095a28d376c935"
-
 [[package]]
 name = "constant_time_eq"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "13418e745008f7349ec7e449155f419a61b92b58a99cc3616942b926825ec76b"
+checksum = "21a53c0a4d288377e7415b53dcfc3c04da5cdc2cc95c8d5ac178b58f0b861ad6"
 
 [[package]]
 name = "cpufeatures"
-version = "0.2.7"
+version = "0.2.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3e4c1eaa2012c47becbbad2ab175484c2a84d1185b566fb2cc5b8707343dfe58"
+checksum = "a17b76ff3a4162b0b27f354a0c87015ddad39d35f9c0c36607a3bdd175dde1f1"
 dependencies = [
  "libc",
 ]
@@ -394,9 +371,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-epoch"
-version = "0.9.14"
+version = "0.9.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "46bd5f3f85273295a9d14aedfb86f6aadbff6d8f5295c4a9edb08e819dcf5695"
+checksum = "ae211234986c545741a7dc064309f67ee1e5ad243d0e48335adc0484d960bcc7"
 dependencies = [
  "autocfg",
  "cfg-if",
@@ -407,9 +384,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.15"
+version = "0.8.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c063cd8cc95f5c377ed0d4b49a4b21f632396ff690e8470c29b3359b346984b"
+checksum = "5a22b2d63d4d1dc0b7f1b6b2747dd0088008a9be28b6ddf0b1e7d335e3037294"
 dependencies = [
  "cfg-if",
 ]
@@ -426,7 +403,7 @@ version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
 dependencies = [
- "generic-array 0.14.7",
+ "generic-array",
  "typenum",
 ]
 
@@ -440,66 +417,27 @@ dependencies = [
 ]
 
 [[package]]
-name = "digest"
-version = "0.8.1"
+name = "deranged"
+version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3d0c8c8752312f9713efd397ff63acb9f85585afbf179282e720e7704954dd5"
-dependencies = [
- "generic-array 0.12.4",
-]
+checksum = "f2696e8a945f658fd14dc3b87242e6b80cd0f36ff04ea560fa39082368847946"
 
 [[package]]
 name = "digest"
-version = "0.9.0"
+version = "0.10.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d3dd60d1080a57a05ab032377049e0591415d2b31afd7028356dbf3cc6dcb066"
+checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
 dependencies = [
- "generic-array 0.14.7",
-]
-
-[[package]]
-name = "digest"
-version = "0.10.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8168378f4e5023e7218c89c891c0fd8ecdb5e5e4f18cb78f38cf245dd021e76f"
-dependencies = [
- "block-buffer 0.10.4",
+ "block-buffer",
  "crypto-common",
  "subtle",
 ]
 
-[[package]]
-name = "directories"
-version = "5.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a49173b84e034382284f27f1af4dcbbd231ffa358c0fe316541a7337f376a35"
-dependencies = [
- "dirs-sys",
-]
-
-[[package]]
-name = "dirs-sys"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "520f05a5cbd335fae5a99ff7a6ab8627577660ee5cfd6a94a6a929b52ff0321c"
-dependencies = [
- "libc",
- "option-ext",
- "redox_users",
- "windows-sys 0.48.0",
-]
-
-[[package]]
-name = "discard"
-version = "1.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "212d0f5754cb6769937f4501cc0e67f4f4483c8d2c3e1e922ee9edbe4ab4c7c0"
-
 [[package]]
 name = "dlopen2"
-version = "0.4.1"
+version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b121caccfc363e4d9a4589528f3bef7c71b83c6ed01c8dc68cbeeb7fd29ec698"
+checksum = "6bc2c7ed06fd72a8513ded8d0d2f6fd2655a85d6885c48cae8625d80faf28c03"
 dependencies = [
  "dlopen2_derive",
  "libc",
@@ -509,20 +447,20 @@ dependencies = [
 
 [[package]]
 name = "dlopen2_derive"
-version = "0.2.0"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3a09ac8bb8c16a282264c379dffba707b9c998afc7506009137f3c6136888078"
+checksum = "f2b99bf03862d7f545ebc28ddd33a665b50865f4dfd84031a393823879bd4c54"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 1.0.109",
+ "syn 2.0.31",
 ]
 
 [[package]]
 name = "either"
-version = "1.8.1"
+version = "1.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7fcaabb2fef8c910e7f4c7ce9f67a1283a1715879a7c230ca9d6d1ae31f16d91"
+checksum = "a26ae43d7bcc3b814de94796a5e736d4029efb0ee900c12e2d54c993ad1a1e07"
 
 [[package]]
 name = "equihash"
@@ -535,14 +473,20 @@ dependencies = [
 ]
 
 [[package]]
-name = "errno"
-version = "0.3.1"
+name = "equivalent"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4bcfec3a70f97c962c307b2d2c56e358cf1d00b558d74262b5f929ee8cc7e73a"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
+[[package]]
+name = "errno"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "136526188508e25c6fef639d7927dfb3e0e3084488bf202267829cf7fc23dbdd"
 dependencies = [
  "errno-dragonfly",
  "libc",
- "windows-sys 0.48.0",
+ "windows-sys",
 ]
 
 [[package]]
@@ -600,12 +544,9 @@ checksum = "7360491ce676a36bf9bb3c56c1aa791658183a54d2744120f27285738d90465a"
 
 [[package]]
 name = "fastrand"
-version = "1.9.0"
+version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e51093e27b0797c359783294ca4f0a911c270184cb10f85783b118614a1501be"
-dependencies = [
- "instant",
-]
+checksum = "6999dc1837253364c2ebb0704ba97994bd874e8f195d665c50b7548f6ea92764"
 
 [[package]]
 name = "ff"
@@ -644,15 +585,6 @@ version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6d5a32815ae3f33302d95fdcb2ce17862f8c65363dcfd29360480ba1001fc9c"
 
-[[package]]
-name = "generic-array"
-version = "0.12.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ffdf9f34f1447443d37393cc6c2b8313aebddcd96906caf34e54c68d8e57d7bd"
-dependencies = [
- "typenum",
-]
-
 [[package]]
 name = "generic-array"
 version = "0.14.7"
@@ -665,9 +597,9 @@ dependencies = [
 
 [[package]]
 name = "getrandom"
-version = "0.2.9"
+version = "0.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c85e1d9ab2eadba7e5040d4e09cbd6d072b76a557ad64e797c2cb9d4da21d7e4"
+checksum = "be4136b2a15dd319360be1c07d9933517ccf0be8f16bf62a3bee4f0d618df427"
 dependencies = [
  "cfg-if",
  "libc",
@@ -676,9 +608,9 @@ dependencies = [
 
 [[package]]
 name = "gimli"
-version = "0.27.2"
+version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad0a93d233ebf96623465aad4046a8d3aa4da22d4f4beba5388838c8a434bbb4"
+checksum = "6fb8d784f27acf97159b40fc4db5ecd8aa23b9ad5ef69cdd136d3bc80665f0c0"
 
 [[package]]
 name = "group"
@@ -734,50 +666,46 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.11.2"
+version = "0.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+checksum = "2c6201b9ff9fd90a5a3bac2e56a830d0caa509576f0e503818ee82c181b3437a"
 dependencies = [
  "ahash",
+ "allocator-api2",
 ]
 
-[[package]]
-name = "hashbrown"
-version = "0.12.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
-
 [[package]]
 name = "hashlink"
-version = "0.7.0"
+version = "0.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7249a3129cbc1ffccd74857f81464a323a152173cdb134e0fd81bc803b29facf"
+checksum = "e8094feaf31ff591f651a2664fb9cfd92bba7a60ce3197265e9482ebe753c8f7"
 dependencies = [
- "hashbrown 0.11.2",
+ "hashbrown",
 ]
 
 [[package]]
 name = "hdwallet"
-version = "0.3.1"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9cd89bf343be18dbe1e505100e48168bbd084760e842a8fed0317d2361470193"
+checksum = "5a03ba7d4c9ea41552cd4351965ff96883e629693ae85005c501bb4b9e1c48a7"
 dependencies = [
  "lazy_static",
  "rand_core",
  "ring",
  "secp256k1",
+ "thiserror",
 ]
 
 [[package]]
 name = "hdwallet-bitcoin"
-version = "0.3.0"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "969c513e03167e65d4bb59f5c51ec3820210975044ad7f218ab801fc169760fa"
+checksum = "4412333586deae44def90f2627065d95928decda2315de17df4551ac32059542"
 dependencies = [
  "base58",
  "hdwallet",
  "hex",
- "ripemd160",
+ "ripemd",
 ]
 
 [[package]]
@@ -788,18 +716,9 @@ checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
 
 [[package]]
 name = "hermit-abi"
-version = "0.2.6"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ee512640fe35acbfb4bb779db6f0d80704c2cacfa2e39b601ef3e3f47d1ae4c7"
-dependencies = [
- "libc",
-]
-
-[[package]]
-name = "hermit-abi"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fed44880c466736ef9a5c5b5facefb5ed0785676d0c02d612db14e54f0d84286"
+checksum = "443144c8cdadd93ebf52ddb4056d257f5b52c04d3c804e657d19eb73fc33668b"
 
 [[package]]
 name = "hex"
@@ -813,26 +732,35 @@ version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6c49c37c09c17a53d937dfbb742eb3a961d65a994e6bcdcf37e7399d0cc8ab5e"
 dependencies = [
- "digest 0.10.6",
+ "digest",
+]
+
+[[package]]
+name = "home"
+version = "0.5.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5444c27eef6923071f7ebcc33e3444508466a76f7a2b93da00ed6e19f30c1ddb"
+dependencies = [
+ "windows-sys",
 ]
 
 [[package]]
 name = "incrementalmerkletree"
-version = "0.3.1"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5ad43a3f5795945459d577f6589cf62a476e92c79b75e70cd954364e14ce17b"
+checksum = "361c467824d4d9d4f284be4b2608800839419dccc4d4608f28345237fe354623"
 dependencies = [
- "serde",
+ "either",
 ]
 
 [[package]]
 name = "indexmap"
-version = "1.9.3"
+version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd070e393353796e801d209ad339e89596eb4c8d430d18ede6a1cced8fafbd99"
+checksum = "d5477fe2230a79769d8dc68e0eabf5437907c0457a5614a9e8dddb67f65eb65d"
 dependencies = [
- "autocfg",
- "hashbrown 0.12.3",
+ "equivalent",
+ "hashbrown",
 ]
 
 [[package]]
@@ -841,27 +769,7 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a0c10553d664a4d0bcff9f4215d0aac67a639cc68ef660840afe309b807bc9f5"
 dependencies = [
- "generic-array 0.14.7",
-]
-
-[[package]]
-name = "instant"
-version = "0.1.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a5bbe824c507c5da5956355e86a746d82e0e1464f65d862cc5e71da70e94b2c"
-dependencies = [
- "cfg-if",
-]
-
-[[package]]
-name = "io-lifetimes"
-version = "1.0.10"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c66c74d2ae7e79a5a8f7ac924adbe38ee42a859c6539ad869eb51f0b52dc220"
-dependencies = [
- "hermit-abi 0.3.1",
- "libc",
- "windows-sys 0.48.0",
+ "generic-array",
 ]
 
 [[package]]
@@ -875,9 +783,9 @@ dependencies = [
 
 [[package]]
 name = "itoa"
-version = "1.0.6"
+version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "453ad9f582a441959e5f0d088b02ce04cfe8d51a8eaf077f12ac6d3e94164ca6"
+checksum = "af150ab688ff2122fcef229be89cb50dd66af9e01a4ff320cc137eecc9bacc38"
 
 [[package]]
 name = "jni"
@@ -901,9 +809,9 @@ checksum = "8eaf4bc02d17cbdd7ff4c7438cafcdf7fb9a4613313ad11b4f8fefe7d3fa0130"
 
 [[package]]
 name = "js-sys"
-version = "0.3.61"
+version = "0.3.64"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "445dde2150c55e483f3d8416706b97ec8e8237c307e5b7b4b8dd15e6af2a0730"
+checksum = "c5f195fe497f702db0f318b07fdd68edb16955aed830df8363d837542f8f935a"
 dependencies = [
  "wasm-bindgen",
 ]
@@ -922,6 +830,15 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "known-folders"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b6f1427d9c43b1cce87434c4d9eca33f43bdbb6246a762aa823a582f74c1684"
+dependencies = [
+ "windows-sys",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -933,21 +850,21 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.142"
+version = "0.2.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6a987beff54b60ffa6d51982e1aa1146bc42f19bd26be28b0586f252fccf5317"
+checksum = "b4668fb0ea861c1df094127ac5f1da3409a82116a4ba74fca2e58ef927159bb3"
 
 [[package]]
 name = "libm"
-version = "0.2.6"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "348108ab3fba42ec82ff6e9564fc4ca0247bdccdc68dd8af9764bbc79c3c8ffb"
+checksum = "f7012b1bbb0719e1097c47611d3898568c546d597c2e74d66f6087edd5233ff4"
 
 [[package]]
 name = "libsqlite3-sys"
-version = "0.22.2"
+version = "0.26.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "290b64917f8b0cb885d9de0f9959fe1f775d7fa12f1da2db9001c1c8ab60f89d"
+checksum = "afc22eff61b133b115c6e8c74e818c628d6d5e7a502afea6f64dee076dd94326"
 dependencies = [
  "cc",
  "pkg-config",
@@ -956,18 +873,15 @@ dependencies = [
 
 [[package]]
 name = "linux-raw-sys"
-version = "0.3.6"
+version = "0.4.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b64f40e5e03e0d54f03845c8197d0291253cdbedfb1cb46b13c2c117554a9f4c"
+checksum = "57bcfdad1b858c2db7c38303a6d2ad4dfaf5eb53dfeb0910128b2c26d6158503"
 
 [[package]]
 name = "log"
-version = "0.4.17"
+version = "0.4.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "abb12e687cfb44aa40f41fc3978ef76448f9b6038cad6aef4259d3c095a2382e"
-dependencies = [
- "cfg-if",
-]
+checksum = "b5e6163cb8c49088c2c36f57875e58ccd8c87c7427f7fbd50ea6710b2f3f2e8f"
 
 [[package]]
 name = "log-panics"
@@ -990,15 +904,15 @@ dependencies = [
 
 [[package]]
 name = "memchr"
-version = "2.5.0"
+version = "2.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+checksum = "8f232d6ef707e1956a43342693d2a31e72989554d58299d7a88738cc95b0d35c"
 
 [[package]]
 name = "memoffset"
-version = "0.8.0"
+version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d61c719bcfbcf5d62b3a09efa6088de8c54bc0bfcd3ea7ae39fcc186108b8de1"
+checksum = "5a634b1c61a95585bd15607c6ab0c4e5b226e695ff2800ba0cdccddf208c406c"
 dependencies = [
  "autocfg",
 ]
@@ -1020,9 +934,9 @@ checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
 
 [[package]]
 name = "miniz_oxide"
-version = "0.6.2"
+version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b275950c28b37e794e8c55d88aeb5e139d0ce23fdbbeda68f8d7174abdf9e8fa"
+checksum = "e7810e0be55b428ada41041c41f32c9f1a42817901b4ccf45fa3d4b6561e74c7"
 dependencies = [
  "adler",
 ]
@@ -1070,9 +984,9 @@ dependencies = [
 
 [[package]]
 name = "num-bigint"
-version = "0.4.3"
+version = "0.4.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f93ab6289c7b344a8a9f60f88d80aa20032336fe78da341afc91c8a2341fc75f"
+checksum = "608e7659b5c3d7cba262d894801b9ec9d00de989e8a82bd4bef91d08da45cdc0"
 dependencies = [
  "autocfg",
  "num-integer",
@@ -1091,43 +1005,37 @@ dependencies = [
 
 [[package]]
 name = "num-traits"
-version = "0.2.15"
+version = "0.2.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "578ede34cf02f8924ab9447f50c28075b4d3e5b269972345e7e0372b38c6cdcd"
+checksum = "f30b0abd723be7e2ffca1272140fac1a2f084c77ec3e123c192b66af1ee9e6c2"
 dependencies = [
  "autocfg",
 ]
 
 [[package]]
 name = "num_cpus"
-version = "1.15.0"
+version = "1.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0fac9e2da13b5eb447a6ce3d392f23a29d8694bff781bf03a16cd9ac8697593b"
+checksum = "4161fcb6d602d4d2081af7c3a45852d875a03dd337a6bfdd6e06407b61342a43"
 dependencies = [
- "hermit-abi 0.2.6",
+ "hermit-abi",
  "libc",
 ]
 
 [[package]]
 name = "object"
-version = "0.30.3"
+version = "0.32.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea86265d3d3dcb6a27fc51bd29a4bf387fae9d2986b823079d4986af253eb439"
+checksum = "9cf5f9dd3933bd50a9e1f149ec995f39ae2c496d31fd772c1fd45ebc27e902b0"
 dependencies = [
  "memchr",
 ]
 
 [[package]]
 name = "once_cell"
-version = "1.17.1"
+version = "1.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b7e5500299e16ebb147ae15a00a942af264cf3688f47923b8fc2cd5858f23ad3"
-
-[[package]]
-name = "opaque-debug"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2839e79665f131bdb5782e51f2c6c9599c133c6098982a54c794358bf432529c"
+checksum = "dd8b5dd2ae5ed71462c540258bedcb51965123ad7e7ccf4b9a8cafaa4a63576d"
 
 [[package]]
 name = "opaque-debug"
@@ -1135,17 +1043,11 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "624a8340c38c1b80fd549087862da4ba43e08858af025b236e509b6649fc13d5"
 
-[[package]]
-name = "option-ext"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "04744f49eae99ab78e0d5c0b603ab218f515ea8cfe5a456d7629ad883a3b6e7d"
-
 [[package]]
 name = "orchard"
-version = "0.4.0"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2c6f418f2c25573923f81a091f38b4b19bc20f6c92b5070fb8f0711e64a2b998"
+checksum = "5d31e68534df32024dcc89a8390ec6d7bef65edd87d91b45cfb481a2eb2d77c5"
 dependencies = [
  "aes",
  "bitvec",
@@ -1230,21 +1132,21 @@ version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "271779f35b581956db91a3e55737327a03aa051e90b1c47aeb189508533adfd7"
 dependencies = [
- "digest 0.10.6",
+ "digest",
  "password-hash",
 ]
 
 [[package]]
 name = "percent-encoding"
-version = "2.2.0"
+version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "478c572c3d73181ff3c2539045f6eb99e5491218eae919370993b890cdbdd98e"
+checksum = "9b2a4787296e9989611394c33f193f676704af1686e70b8f8033ab5ba9a35a94"
 
 [[package]]
 name = "petgraph"
-version = "0.6.3"
+version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4dd7d28ee937e54fe3080c91faa1c3a46c06de6252988a7f4592ba2310ef22a4"
+checksum = "e1d3afd2628e69da2be385eb6f2fd57c8ac7977ceeff6dc166ff1657b0e386a9"
 dependencies = [
  "fixedbitset",
  "indexmap",
@@ -1252,15 +1154,15 @@ dependencies = [
 
 [[package]]
 name = "pin-project-lite"
-version = "0.2.9"
+version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e0a7ae3ac2f1173085d398531c705756c94a4c56843785df85a60c1a0afac116"
+checksum = "8afb450f006bf6385ca15ef45d71d2288452bc3683ce2e2cacc0d18e4be60b58"
 
 [[package]]
 name = "pkg-config"
-version = "0.3.26"
+version = "0.3.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6ac9a59f73473f1b8d852421e59e64809f025994837ef743615c6d0c5b305160"
+checksum = "26072860ba924cbfa98ea39c8c19b4dd6a4a25423dbdf219c1eca91aa0cf6964"
 
 [[package]]
 name = "poly1305"
@@ -1269,7 +1171,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8159bd90725d2df49889a078b54f4f79e87f1f8a8444194cdca81d38f5393abf"
 dependencies = [
  "cpufeatures",
- "opaque-debug 0.3.0",
+ "opaque-debug",
  "universal-hash",
 ]
 
@@ -1281,34 +1183,28 @@ checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
 [[package]]
 name = "prettyplease"
-version = "0.1.25"
+version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6c8646e95016a7a6c4adea95bafa8a16baab64b583356217f2c85db4a39d9a86"
+checksum = "ae005bd773ab59b4725093fd7df83fd7892f7d8eafb48dbd7de6e024e4215f9d"
 dependencies = [
  "proc-macro2",
- "syn 1.0.109",
+ "syn 2.0.31",
 ]
 
-[[package]]
-name = "proc-macro-hack"
-version = "0.5.20+deprecated"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc375e1527247fe1a97d8b7156678dfe7c1af2fc075c9a4db3690ecd2a148068"
-
 [[package]]
 name = "proc-macro2"
-version = "1.0.56"
+version = "1.0.66"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+checksum = "18fb31db3f9bddb2ea821cde30a9f70117e3f119938b5ee630b7403aa6e2ead9"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "prost"
-version = "0.11.9"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b82eaa1d779e9a4bc1c3217db8ffbeabaae1dca241bf70183242128d48681cd"
+checksum = "aa8473a65b88506c106c28ae905ca4a2b83a2993640467a41bb3080627ddfd2c"
 dependencies = [
  "bytes",
  "prost-derive",
@@ -1316,53 +1212,53 @@ dependencies = [
 
 [[package]]
 name = "prost-build"
-version = "0.11.9"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "119533552c9a7ffacc21e099c24a0ac8bb19c2a2a3f363de84cd9b844feab270"
+checksum = "30d3e647e9eb04ddfef78dfee2d5b3fefdf94821c84b710a3d8ebc89ede8b164"
 dependencies = [
  "bytes",
  "heck",
  "itertools",
- "lazy_static",
  "log",
  "multimap",
+ "once_cell",
  "petgraph",
  "prettyplease",
  "prost",
  "prost-types",
  "regex",
- "syn 1.0.109",
+ "syn 2.0.31",
  "tempfile",
  "which",
 ]
 
 [[package]]
 name = "prost-derive"
-version = "0.11.9"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5d2d8d10f3c6ded6da8b05b5fb3b8a5082514344d56c9f871412d29b4e075b4"
+checksum = "56075c27b20ae524d00f247b8a4dc333e5784f889fe63099f8e626bc8d73486c"
 dependencies = [
  "anyhow",
  "itertools",
  "proc-macro2",
  "quote",
- "syn 1.0.109",
+ "syn 2.0.31",
 ]
 
 [[package]]
 name = "prost-types"
-version = "0.11.9"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "213622a1460818959ac1181aaeb2dc9c7f63df720db7d788b3e24eacd1983e13"
+checksum = "cebe0a918c97f86c217b0f76fd754e966f8b9f41595095cf7d74cb4e59d730f6"
 dependencies = [
  "prost",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.26"
+version = "1.0.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4424af4bf778aae2051a77b60283332f386554255d722233d09fbfc7e30da2fc"
+checksum = "5267fca4496028628a95160fc423a33e8b2e6af8a5302579e322e4b520293cae"
 dependencies = [
  "proc-macro2",
 ]
@@ -1427,9 +1323,9 @@ dependencies = [
 
 [[package]]
 name = "reddsa"
-version = "0.5.0"
+version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "54b34d2c0df43159d2ff79d3cf929c9f11415529127344edb8160ad2be499fcd"
+checksum = "78a5191930e84973293aa5f532b513404460cd2216c1cfb76d08748c15b40b02"
 dependencies = [
  "blake2b_simd",
  "byteorder",
@@ -1456,49 +1352,43 @@ dependencies = [
  "zeroize",
 ]
 
-[[package]]
-name = "redox_syscall"
-version = "0.2.16"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fb5a58c1855b4b6819d59012155603f0b22ad30cad752600aadfcb695265519a"
-dependencies = [
- "bitflags",
-]
-
 [[package]]
 name = "redox_syscall"
 version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "567664f262709473930a4bf9e51bf2ebf3348f2e748ccc50dea20646858f8f29"
 dependencies = [
- "bitflags",
-]
-
-[[package]]
-name = "redox_users"
-version = "0.4.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b033d837a7cf162d7993aded9304e30a83213c648b6e389db233191f891e5c2b"
-dependencies = [
- "getrandom",
- "redox_syscall 0.2.16",
- "thiserror",
+ "bitflags 1.3.2",
 ]
 
 [[package]]
 name = "regex"
-version = "1.8.1"
+version = "1.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af83e617f331cc6ae2da5443c602dfa5af81e517212d9d611a5b3ba1777b5370"
+checksum = "697061221ea1b4a94a624f67d0ae2bfe4e22b8a17b6a192afb11046542cc8c47"
 dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c2f401f4955220693b56f8ec66ee9c78abffd8d1c4f23dc41a23839eb88f0795"
+dependencies = [
+ "aho-corasick",
+ "memchr",
  "regex-syntax",
 ]
 
 [[package]]
 name = "regex-syntax"
-version = "0.7.1"
+version = "0.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a5996294f19bd3aae0453a862ad728f60e6600695733dd5df01da90c54363a3c"
+checksum = "dbb5fb1acd8a1a18b3dd5be62d25485eb770e05afb408a9627d14d451bae12da"
 
 [[package]]
 name = "ring"
@@ -1521,33 +1411,20 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bd124222d17ad93a644ed9d011a40f4fb64aa54275c08cc216524a9ea82fb09f"
 dependencies = [
- "digest 0.10.6",
-]
-
-[[package]]
-name = "ripemd160"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad5112e0dbbb87577bfbc56c42450235e3012ce336e29c5befd7807bd626da4a"
-dependencies = [
- "block-buffer 0.7.3",
- "digest 0.8.1",
- "opaque-debug 0.2.3",
+ "digest",
 ]
 
 [[package]]
 name = "rusqlite"
-version = "0.25.4"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c4b1eaf239b47034fb450ee9cdedd7d0226571689d8823030c4b6c2cb407152"
+checksum = "549b9d036d571d42e6e85d1c1425e2ac83491075078ca9a15be021c56b1641f2"
 dependencies = [
- "bitflags",
+ "bitflags 2.4.0",
  "fallible-iterator",
  "fallible-streaming-iterator",
  "hashlink",
- "lazy_static",
  "libsqlite3-sys",
- "memchr",
  "smallvec",
  "time",
 ]
@@ -1558,35 +1435,19 @@ version = "0.1.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d626bb9dae77e28219937af045c257c28bfd3f69333c512553507f5f9798cb76"
 
-[[package]]
-name = "rustc_version"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
-dependencies = [
- "semver",
-]
-
 [[package]]
 name = "rustix"
-version = "0.37.18"
+version = "0.38.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8bbfc1d1c7c40c01715f47d71444744a81669ca84e8b63e25a55e169b1f86433"
+checksum = "c0c3dde1fc030af041adc40e79c0e7fbcf431dd24870053d187d7c66e4b87453"
 dependencies = [
- "bitflags",
+ "bitflags 2.4.0",
  "errno",
- "io-lifetimes",
  "libc",
  "linux-raw-sys",
- "windows-sys 0.48.0",
+ "windows-sys",
 ]
 
-[[package]]
-name = "ryu"
-version = "1.0.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f91339c0467de62360649f8d3e185ca8de4224ff281f66000de5eb2a77a79041"
-
 [[package]]
 name = "same-file"
 version = "1.0.6"
@@ -1610,9 +1471,9 @@ dependencies = [
 
 [[package]]
 name = "schemer-rusqlite"
-version = "0.2.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c1f34ab2dd976536b8518fe5b868756cf6e6caec89f38d8b6f432ba27f1d5f27"
+checksum = "0fb5ac1fa52c58e2c6a618e3149d464e7ad8d0effca74990ea29c1fe2338b3b1"
 dependencies = [
  "rusqlite",
  "schemer",
@@ -1621,24 +1482,24 @@ dependencies = [
 
 [[package]]
 name = "scopeguard"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
+checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
 [[package]]
 name = "secp256k1"
-version = "0.21.3"
+version = "0.26.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c42e6f1735c5f00f51e43e28d6634141f2bcad10931b2609ddd74a86d751260"
+checksum = "4124a35fe33ae14259c490fd70fa199a32b9ce9502f2ee6bc4f81ec06fa65894"
 dependencies = [
  "secp256k1-sys",
 ]
 
 [[package]]
 name = "secp256k1-sys"
-version = "0.4.2"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "957da2573cde917463ece3570eab4a0b3f19de6f1646cde62e6fd3868f566036"
+checksum = "70a129b9e9efbfb223753b9163c4ab3b13cff7fd9c7f010fbac25ab4099fa07e"
 dependencies = [
  "cc",
 ]
@@ -1652,89 +1513,35 @@ dependencies = [
  "zeroize",
 ]
 
-[[package]]
-name = "semver"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
-dependencies = [
- "semver-parser",
-]
-
-[[package]]
-name = "semver-parser"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
-
 [[package]]
 name = "serde"
-version = "1.0.160"
+version = "1.0.188"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bb2f3770c8bce3bcda7e149193a069a0f4365bda1fa5cd88e03bca26afc1216c"
+checksum = "cf9e0fcba69a370eed61bcf2b728575f726b50b55cba78064753d708ddc7549e"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.160"
+version = "1.0.188"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "291a097c63d8497e00160b166a967a4a79c64f3facdd01cbd7502231688d77df"
+checksum = "4eca7ac642d82aa35b60049a6eccb4be6be75e599bd2e9adb5f875a737654af2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.15",
-]
-
-[[package]]
-name = "serde_json"
-version = "1.0.96"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "057d394a50403bcac12672b2b18fb387ab6d289d957dab67dd201875391e52f1"
-dependencies = [
- "itoa",
- "ryu",
- "serde",
-]
-
-[[package]]
-name = "sha1"
-version = "0.6.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c1da05c97445caa12d05e848c4a4fcbbea29e748ac28f7e80e9b010392063770"
-dependencies = [
- "sha1_smol",
-]
-
-[[package]]
-name = "sha1_smol"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ae1a47186c03a32177042e55dbc5fd5aee900b8e0069a8d70fba96a9375cd012"
-
-[[package]]
-name = "sha2"
-version = "0.9.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4d58a1e1bf39749807d89cf2d98ac2dfa0ff1cb3faa38fbb64dd88ac8013d800"
-dependencies = [
- "block-buffer 0.9.0",
- "cfg-if",
- "cpufeatures",
- "digest 0.9.0",
- "opaque-debug 0.3.0",
+ "syn 2.0.31",
 ]
 
 [[package]]
 name = "sha2"
-version = "0.10.6"
+version = "0.10.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "82e6b795fe2e3b1e845bafcb27aa35405c4d47cdfc92af5fc8d3002f76cebdc0"
+checksum = "479fb9d862239e610720565ca91403019f2f00410f1864c5aa7479b950a76ed8"
 dependencies = [
  "cfg-if",
  "cpufeatures",
- "digest 0.10.6",
+ "digest",
 ]
 
 [[package]]
@@ -1747,10 +1554,22 @@ dependencies = [
 ]
 
 [[package]]
-name = "smallvec"
-version = "1.10.0"
+name = "shardtree"
+version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a507befe795404456341dfab10cef66ead4c041f62b8b11bbb92bffe5d0953e0"
+checksum = "c19f96dde3a8693874f7e7c53d95616569b4009379a903789efbd448f4ea9cc7"
+dependencies = [
+ "bitflags 2.4.0",
+ "either",
+ "incrementalmerkletree",
+ "tracing",
+]
+
+[[package]]
+name = "smallvec"
+version = "1.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62bb4feee49fdd9f707ef802e22365a35de4b7b299de4763d44bfea899442ff9"
 
 [[package]]
 name = "spin"
@@ -1758,70 +1577,12 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
-[[package]]
-name = "standback"
-version = "0.2.17"
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-[[package]]
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-
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@@ -1841,9 +1602,9 @@ dependencies = [
 
 [[package]]
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 dependencies = [
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@@ -1870,35 +1631,35 @@ checksum = "55937e1799185b12863d447f42597ed69d9928686b8d88a1df17376a097d8369"
 
 [[package]]
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 dependencies = [
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+ "redox_syscall",
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- "windows-sys 0.45.0",
+ "windows-sys",
 ]
 
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 [[package]]
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 dependencies = [
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+ "syn 2.0.31",
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 [[package]]
@@ -1913,40 +1674,30 @@ dependencies = [
 
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 dependencies = [
- "const_fn",
- "libc",
- "standback",
- "stdweb",
+ "deranged",
+ "itoa",
+ "serde",
+ "time-core",
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- "version_check",
- "winapi",
 ]
 
+[[package]]
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+checksum = "7300fbefb4dadc1af235a9cef3737cea692a9d97e1b9cbcd4ebdae6f8868e6fb"
+
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+checksum = "1a942f44339478ef67935ab2bbaec2fb0322496cf3cbe84b261e06ac3814c572"
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-dependencies = [
- "proc-macro-hack",
- "proc-macro2",
- "quote",
- "standback",
- "syn 1.0.109",
+ "time-core",
 ]
 
 [[package]]
@@ -1966,15 +1717,15 @@ checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 
 [[package]]
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-checksum = "a6fdaae4c2c638bb70fe42803a26fbd6fc6ac8c72f5c59f67ecc2a2dcabf4b07"
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 dependencies = [
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  "proc-macro2",
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  "quote",
- "syn 1.0.109",
+ "syn 2.0.31",
 ]
 
 [[package]]
@@ -1991,20 +1742,20 @@ dependencies = [
 
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+ "syn 2.0.31",
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@@ -2055,9 +1806,9 @@ dependencies = [
 
 [[package]]
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 [[package]]
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@@ -2076,9 +1827,9 @@ checksum = "f962df74c8c05a667b5ee8bcf162993134c104e96440b663c8daa176dc772d8c"
 
 [[package]]
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@@ -2092,9 +1843,9 @@ checksum = "a156c684c91ea7d62626509bce3cb4e1d9ed5c4d978f7b4352658f96a4c26b4a"
 
 [[package]]
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 [[package]]
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@@ -2116,9 +1867,9 @@ checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
 [[package]]
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 dependencies = [
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@@ -2132,9 +1883,9 @@ checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
 [[package]]
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@@ -2142,24 +1893,24 @@ dependencies = [
 
 [[package]]
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 dependencies = [
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+ "syn 2.0.31",
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 [[package]]
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@@ -2167,28 +1918,28 @@ dependencies = [
 
 [[package]]
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 dependencies = [
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 [[package]]
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 [[package]]
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 dependencies = [
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@@ -2196,13 +1947,14 @@ dependencies = [
 
 [[package]]
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 dependencies = [
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- "libc",
+ "home",
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+ "rustix",
 ]
 
 [[package]]
@@ -2236,137 +1988,71 @@ version = "0.4.0"
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 checksum = "677d2418bec65e3338edb076e806bc1ec15693c5d0104683f2efe857f61056a9"
 dependencies = [
- "windows-targets 0.48.0",
+ "windows-targets",
 ]
 
 [[package]]
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- "windows_x86_64_gnu 0.48.0",
- "windows_x86_64_gnullvm 0.48.0",
- "windows_x86_64_msvc 0.48.0",
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
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 [[package]]
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-name = "windows_x86_64_msvc"
-version = "0.48.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1a515f5799fe4961cb532f983ce2b23082366b898e52ffbce459c86f67c8378a"
+checksum = "ed94fce61571a4006852b7389a063ab983c02eb1bb37b47f8272ce92d06d9538"
 
 [[package]]
 name = "wyz"
@@ -2377,6 +2063,12 @@ dependencies = [
  "tap",
 ]
 
+[[package]]
+name = "xdg"
+version = "2.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "213b7324336b53d2414b2db8537e56544d981803139155afa84f76eeebb7a546"
+
 [[package]]
 name = "zcash-android-wallet-sdk"
 version = "0.0.4"
@@ -2391,7 +2083,9 @@ dependencies = [
  "log-panics",
  "orchard",
  "paranoid-android",
+ "prost",
  "rayon",
+ "rusqlite",
  "schemer",
  "secp256k1",
  "secrecy",
@@ -2406,9 +2100,9 @@ dependencies = [
 
 [[package]]
 name = "zcash_address"
-version = "0.2.1"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "52be35a205369d480378646bff9c9fedafd8efe8af1e0e54bb858f405883f2b2"
+checksum = "8944af5c206cf2e37020ad54618e1825501b98548d35a638b73e0ec5762df8d5"
 dependencies = [
  "bech32",
  "bs58",
@@ -2418,9 +2112,9 @@ dependencies = [
 
 [[package]]
 name = "zcash_client_backend"
-version = "0.9.0"
+version = "0.10.0-rc.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a55db8d2cb4ca82a71fa66ccd9fa5b211f5ab90c866721311ddd85f8f90d0701"
+checksum = "432f902a7308d10435351275a33629c61905f5b4289dc8b89259b1b8c1a87a86"
 dependencies = [
  "base64",
  "bech32",
@@ -2430,6 +2124,8 @@ dependencies = [
  "crossbeam-channel",
  "group",
  "hdwallet",
+ "hex",
+ "incrementalmerkletree",
  "memuse",
  "nom",
  "orchard",
@@ -2437,6 +2133,7 @@ dependencies = [
  "prost",
  "rayon",
  "secrecy",
+ "shardtree",
  "subtle",
  "time",
  "tonic-build",
@@ -2450,23 +2147,28 @@ dependencies = [
 
 [[package]]
 name = "zcash_client_sqlite"
-version = "0.7.1"
+version = "0.8.0-rc.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6be255cd5f217fa8bbe599cf07d56ded68b1f43180dbeda1822bee851f5f1971"
+checksum = "a7f5ac4a1ff9258f215b090d97df506c0bcb3ada3f13aa388cdceeb69f67492d"
 dependencies = [
  "bs58",
+ "byteorder",
  "group",
  "hdwallet",
+ "incrementalmerkletree",
  "jubjub",
+ "maybe-rayon",
  "prost",
  "rusqlite",
  "schemer",
  "schemer-rusqlite",
  "secrecy",
+ "shardtree",
  "time",
  "tracing",
  "uuid",
  "zcash_client_backend",
+ "zcash_encoding",
  "zcash_primitives",
 ]
 
@@ -2482,9 +2184,9 @@ dependencies = [
 
 [[package]]
 name = "zcash_note_encryption"
-version = "0.3.0"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2eb2149e6cd5fbee36c5b87c601715a8c35554602f7fe84af38b636afa2db318"
+checksum = "5b4580cd6cee12e44421dac43169be8d23791650816bdb34e6ddfa70ac89c1c5"
 dependencies = [
  "chacha20",
  "chacha20poly1305",
@@ -2495,9 +2197,9 @@ dependencies = [
 
 [[package]]
 name = "zcash_primitives"
-version = "0.11.0"
+version = "0.13.0-rc.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "914d2195a478d5b63191584dff126f552751115181857b290211ec88e68acc3e"
+checksum = "0cc4391d9325e0a51a7cbff02b5c4b5472d66087bd9c903ddb12dea7ec22f3e0"
 dependencies = [
  "aes",
  "bip0039",
@@ -2522,7 +2224,7 @@ dependencies = [
  "rand_core",
  "ripemd",
  "secp256k1",
- "sha2 0.10.6",
+ "sha2",
  "subtle",
  "zcash_address",
  "zcash_encoding",
@@ -2531,20 +2233,22 @@ dependencies = [
 
 [[package]]
 name = "zcash_proofs"
-version = "0.11.0"
+version = "0.13.0-rc.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5c8147884952748b00aa443d36511ae2d7b49acfec74cfd39c0959fbb61ef14"
+checksum = "48f22eff3bdc382327ef28f809024ddc89ec6d903ba71be629b2cbea34afdda2"
 dependencies = [
  "bellman",
  "blake2b_simd",
  "bls12_381",
- "directories",
  "group",
+ "home",
  "jubjub",
+ "known-folders",
  "lazy_static",
  "rand_core",
  "redjubjub",
  "tracing",
+ "xdg",
  "zcash_primitives",
 ]
 
@@ -2565,5 +2269,5 @@ checksum = "ce36e65b0d2999d2aafac989fb249189a141aee1f53c612c1f37d72631959f69"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.15",
+ "syn 2.0.31",
 ]
diff --git a/backend-lib/Cargo.toml b/backend-lib/Cargo.toml
index 0d72c256..6b634645 100644
--- a/backend-lib/Cargo.toml
+++ b/backend-lib/Cargo.toml
@@ -12,19 +12,21 @@ rust-version = "1.60"
 
 [dependencies]
 failure = "0.1"
-hdwallet = "0.3.1"
-hdwallet-bitcoin = "0.3"
+hdwallet = "0.4"
+hdwallet-bitcoin = "0.4"
 hex = "0.4"
 jni = { version = "0.20", default-features = false }
+prost = "0.12"
+rusqlite = "0.29"
 schemer = "0.2"
-secp256k1 = "0.21"
+secp256k1 = "0.26"
 secrecy = "0.8"
-zcash_address = "0.2"
-zcash_client_backend = { version = "0.9", features = ["transparent-inputs", "unstable"] }
-zcash_client_sqlite = { version = "0.7.1", features = ["transparent-inputs", "unstable"] }
-zcash_primitives = "0.11"
-zcash_proofs = "0.11"
-orchard = { version = "0.4", default-features = false }
+zcash_address = "0.3"
+zcash_client_backend = { version = "=0.10.0-rc.2", features = ["transparent-inputs", "unstable"] }
+zcash_client_sqlite = { version = "=0.8.0-rc.3", features = ["transparent-inputs", "unstable"] }
+zcash_primitives = "=0.13.0-rc.1"
+zcash_proofs = "=0.13.0-rc.1"
+orchard = { version = "0.6", default-features = false }
 
 # Initialization
 rayon = "1.7"
@@ -36,7 +38,7 @@ tracing = "0.1"
 tracing-subscriber = "0.3"
 
 # Conditional access to newer NDK features
-dlopen2 = "0.4"
+dlopen2 = "0.6"
 libc = "0.2"
 
 ## Uncomment this to test librustzcash changes locally
diff --git a/backend-lib/build.gradle.kts b/backend-lib/build.gradle.kts
index 21e0e8a6..aa0027a3 100644
--- a/backend-lib/build.gradle.kts
+++ b/backend-lib/build.gradle.kts
@@ -104,6 +104,9 @@ dependencies {
     implementation(libs.kotlinx.coroutines.core)
     implementation(libs.kotlinx.coroutines.android)
 
+    // Tests
+    testImplementation(libs.kotlin.test)
+
     androidTestImplementation(libs.androidx.multidex)
     androidTestImplementation(libs.androidx.test.runner)
     androidTestImplementation(libs.androidx.test.junit)
diff --git a/backend-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/jni/RustDerivationToolTest.kt b/backend-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/jni/RustDerivationToolTest.kt
index f5efd906..f7a7d4af 100644
--- a/backend-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/jni/RustDerivationToolTest.kt
+++ b/backend-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/jni/RustDerivationToolTest.kt
@@ -1,7 +1,6 @@
 package cash.z.ecc.android.sdk.internal.jni
 
 import cash.z.ecc.android.bip39.Mnemonics
-import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.test.runTest
 import org.junit.Test
 import kotlin.test.assertContentEquals
@@ -15,7 +14,6 @@ class RustDerivationToolTest {
     }
 
     @Test
-    @OptIn(ExperimentalCoroutinesApi::class)
     fun create_spending_key_does_not_mutate_passed_bytes() = runTest {
         val bytesOne = Mnemonics.MnemonicCode(SEED_PHRASE).toEntropy()
         val bytesTwo = Mnemonics.MnemonicCode(SEED_PHRASE).toEntropy()
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/Backend.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/Backend.kt
index 295a76f6..d0958510 100644
--- a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/Backend.kt
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/Backend.kt
@@ -1,9 +1,10 @@
 package cash.z.ecc.android.sdk.internal
 
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.internal.model.JniScanProgress
+import cash.z.ecc.android.sdk.internal.model.JniScanRange
+import cash.z.ecc.android.sdk.internal.model.JniSubtreeRoot
 import cash.z.ecc.android.sdk.internal.model.JniUnifiedSpendingKey
-import java.lang.RuntimeException
-import kotlin.jvm.Throws
 
 /**
  * Contract defining the exposed capabilities of the Rust backend.
@@ -25,37 +26,34 @@ interface Backend {
         to: String,
         value: Long,
         memo: ByteArray? = byteArrayOf()
-    ): Long
+    ): ByteArray
 
     suspend fun shieldToAddress(
         account: Int,
         unifiedSpendingKey: ByteArray,
         memo: ByteArray? = byteArrayOf()
-    ): Long
+    ): ByteArray
 
     suspend fun decryptAndStoreTransaction(tx: ByteArray)
 
     /**
-     * @param keys A list of UFVKs to initialize the accounts table with
+     * Sets up the internal structure of the data database.
+     *
+     * If `seed` is `null`, database migrations will be attempted without it.
+     *
+     * @return 0 if successful, 1 if the seed must be provided in order to execute the requested migrations, or -1
+     * otherwise.
+     *
      * @throws RuntimeException as a common indicator of the operation failure
      */
     @Throws(RuntimeException::class)
-    suspend fun initAccountsTable(vararg keys: String)
+    suspend fun initDataDb(seed: ByteArray?): Int
 
     /**
      * @throws RuntimeException as a common indicator of the operation failure
      */
     @Throws(RuntimeException::class)
-    suspend fun initBlocksTable(
-        checkpointHeight: Long,
-        checkpointHash: String,
-        checkpointTime: Long,
-        checkpointSaplingTree: String,
-    )
-
-    suspend fun initDataDb(seed: ByteArray?): Int
-
-    suspend fun createAccount(seed: ByteArray): JniUnifiedSpendingKey
+    suspend fun createAccount(seed: ByteArray, treeState: ByteArray, recoverUntil: Long?): JniUnifiedSpendingKey
 
     fun isValidShieldedAddr(addr: String): Boolean
 
@@ -71,6 +69,10 @@ interface Backend {
 
     suspend fun listTransparentReceivers(account: Int): List<String>
 
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
     suspend fun getBalance(account: Int): Long
 
     fun getBranchIdForHeight(height: Long): Long
@@ -79,14 +81,12 @@ interface Backend {
      * @throws RuntimeException as a common indicator of the operation failure
      */
     @Throws(RuntimeException::class)
-    suspend fun getReceivedMemoAsUtf8(idNote: Long): String?
+    suspend fun getMemoAsUtf8(txId: ByteArray, outputIndex: Int): String?
 
     /**
      * @throws RuntimeException as a common indicator of the operation failure
      */
     @Throws(RuntimeException::class)
-    suspend fun getSentMemoAsUtf8(idNote: Long): String?
-
     suspend fun getVerifiedBalance(account: Int): Long
 
     suspend fun getNearestRewindHeight(height: Long): Long
@@ -101,7 +101,57 @@ interface Backend {
      * @throws RuntimeException as a common indicator of the operation failure
      */
     @Throws(RuntimeException::class)
-    suspend fun scanBlocks(limit: Long?)
+    suspend fun putSaplingSubtreeRoots(
+        startIndex: Long,
+        roots: List<JniSubtreeRoot>,
+    )
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun updateChainTip(height: Long)
+
+    /**
+     * Returns the height to which the wallet has been fully scanned.
+     *
+     * This is the height for which the wallet has fully trial-decrypted this and all
+     * preceding blocks above the wallet's birthday height.
+     *
+     * @return The height to which the wallet has been fully scanned, or Null if no blocks have been scanned.
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    suspend fun getFullyScannedHeight(): Long?
+
+    /**
+     * Returns the maximum height that the wallet has scanned.
+     *
+     * If the wallet is fully synced, this will be equivalent to `getFullyScannedHeight`;
+     * otherwise the maximal scanned height is likely to be greater than the fully scanned
+     * height due to the fact that out-of-order scanning can leave gaps.
+     *
+     * @return The maximum height that the wallet has scanned, or Null if no blocks have been scanned.
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    suspend fun getMaxScannedHeight(): Long?
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun getScanProgress(): JniScanProgress?
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun suggestScanRanges(): List<JniScanRange>
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun scanBlocks(fromHeight: Long, limit: Long)
 
     /**
      * @throws RuntimeException as a common indicator of the operation failure
@@ -112,18 +162,12 @@ interface Backend {
     /**
      * @return The latest height in the CompactBlock cache metadata DB, or Null if no blocks have been cached.
      */
-    suspend fun getLatestHeight(): Long?
+    suspend fun getLatestCacheHeight(): Long?
 
     suspend fun findBlockMetadata(height: Long): JniBlockMeta?
 
     suspend fun rewindBlockMetadataToHeight(height: Long)
 
-    /**
-     * @param limit The limit provides an efficient way how to restrict the portion of blocks, which will be validated.
-     * @return Null if successful. If an error occurs, the height will be the blockheight where the error was detected.
-     */
-    suspend fun validateCombinedChainOrErrorHeight(limit: Long?): Long?
-
     suspend fun getVerifiedTransparentBalance(address: String): Long
     suspend fun getTotalTransparentBalance(address: String): Long
 
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/NumberExt.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/NumberExt.kt
new file mode 100644
index 00000000..0ad93baf
--- /dev/null
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/NumberExt.kt
@@ -0,0 +1,7 @@
+@file:Suppress("ktlint:standard:filename")
+
+package cash.z.ecc.android.sdk.internal.ext
+
+fun Long.isInUIntRange(): Boolean {
+    return this >= 0L && this <= UInt.MAX_VALUE.toLong()
+}
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/jni/RustBackend.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/jni/RustBackend.kt
index ed6dcbf5..b1307c3f 100644
--- a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/jni/RustBackend.kt
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/jni/RustBackend.kt
@@ -5,6 +5,9 @@ import cash.z.ecc.android.sdk.internal.SdkDispatchers
 import cash.z.ecc.android.sdk.internal.ext.deleteRecursivelySuspend
 import cash.z.ecc.android.sdk.internal.ext.deleteSuspend
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.internal.model.JniScanProgress
+import cash.z.ecc.android.sdk.internal.model.JniScanRange
+import cash.z.ecc.android.sdk.internal.model.JniSubtreeRoot
 import cash.z.ecc.android.sdk.internal.model.JniUnifiedSpendingKey
 import kotlinx.coroutines.withContext
 import java.io.File
@@ -66,42 +69,17 @@ class RustBackend private constructor(
         )
     }
 
-    override suspend fun createAccount(seed: ByteArray): JniUnifiedSpendingKey {
+    override suspend fun createAccount(
+        seed: ByteArray,
+        treeState: ByteArray,
+        recoverUntil: Long?
+    ): JniUnifiedSpendingKey {
         return withContext(SdkDispatchers.DATABASE_IO) {
             createAccount(
                 dataDbFile.absolutePath,
                 seed,
-                networkId = networkId
-            )
-        }
-    }
-
-    /**
-     * @param keys A list of UFVKs to initialize the accounts table with
-     */
-    override suspend fun initAccountsTable(vararg keys: String) {
-        return withContext(SdkDispatchers.DATABASE_IO) {
-            initAccountsTableWithKeys(
-                dataDbFile.absolutePath,
-                keys,
-                networkId = networkId
-            )
-        }
-    }
-
-    override suspend fun initBlocksTable(
-        checkpointHeight: Long,
-        checkpointHash: String,
-        checkpointTime: Long,
-        checkpointSaplingTree: String,
-    ) {
-        return withContext(SdkDispatchers.DATABASE_IO) {
-            initBlocksTable(
-                dataDbFile.absolutePath,
-                checkpointHeight,
-                checkpointHash,
-                checkpointTime,
-                checkpointSaplingTree,
+                treeState,
+                recoverUntil ?: -1,
                 networkId = networkId
             )
         }
@@ -154,20 +132,12 @@ class RustBackend private constructor(
         return longValue
     }
 
-    override suspend fun getReceivedMemoAsUtf8(idNote: Long) =
+    override suspend fun getMemoAsUtf8(txId: ByteArray, outputIndex: Int) =
         withContext(SdkDispatchers.DATABASE_IO) {
-            getReceivedMemoAsUtf8(
+            getMemoAsUtf8(
                 dataDbFile.absolutePath,
-                idNote,
-                networkId = networkId
-            )
-        }
-
-    override suspend fun getSentMemoAsUtf8(idNote: Long) =
-        withContext(SdkDispatchers.DATABASE_IO) {
-            getSentMemoAsUtf8(
-                dataDbFile.absolutePath,
-                idNote,
+                txId,
+                outputIndex,
                 networkId = networkId
             )
         }
@@ -180,9 +150,9 @@ class RustBackend private constructor(
             )
         }
 
-    override suspend fun getLatestHeight() =
+    override suspend fun getLatestCacheHeight() =
         withContext(SdkDispatchers.DATABASE_IO) {
-            val height = getLatestHeight(fsBlockDbRoot.absolutePath)
+            val height = getLatestCacheHeight(fsBlockDbRoot.absolutePath)
 
             if (-1L == height) {
                 null
@@ -207,22 +177,6 @@ class RustBackend private constructor(
             )
         }
 
-    override suspend fun validateCombinedChainOrErrorHeight(limit: Long?) =
-        withContext(SdkDispatchers.DATABASE_IO) {
-            val validationResult = validateCombinedChain(
-                dbCachePath = fsBlockDbRoot.absolutePath,
-                dbDataPath = dataDbFile.absolutePath,
-                limit = limit ?: -1,
-                networkId = networkId
-            )
-
-            if (-1L == validationResult) {
-                null
-            } else {
-                validationResult
-            }
-        }
-
     override suspend fun getVerifiedTransparentBalance(address: String): Long =
         withContext(SdkDispatchers.DATABASE_IO) {
             getVerifiedTransparentBalance(
@@ -264,12 +218,79 @@ class RustBackend private constructor(
             )
         }
 
-    override suspend fun scanBlocks(limit: Long?) {
+    override suspend fun putSaplingSubtreeRoots(
+        startIndex: Long,
+        roots: List<JniSubtreeRoot>,
+    ) = withContext(SdkDispatchers.DATABASE_IO) {
+        putSaplingSubtreeRoots(
+            dataDbFile.absolutePath,
+            startIndex,
+            roots.toTypedArray(),
+            networkId = networkId
+        )
+    }
+
+    override suspend fun updateChainTip(height: Long) =
+        withContext(SdkDispatchers.DATABASE_IO) {
+            updateChainTip(
+                dataDbFile.absolutePath,
+                height,
+                networkId = networkId
+            )
+        }
+
+    override suspend fun getFullyScannedHeight() =
+        withContext(SdkDispatchers.DATABASE_IO) {
+            val height = getFullyScannedHeight(
+                dataDbFile.absolutePath,
+                networkId = networkId
+            )
+
+            if (-1L == height) {
+                null
+            } else {
+                height
+            }
+        }
+
+    override suspend fun getMaxScannedHeight() =
+        withContext(SdkDispatchers.DATABASE_IO) {
+            val height = getMaxScannedHeight(
+                dataDbFile.absolutePath,
+                networkId = networkId
+            )
+
+            if (-1L == height) {
+                null
+            } else {
+                height
+            }
+        }
+
+    override suspend fun getScanProgress(): JniScanProgress? =
+        withContext(SdkDispatchers.DATABASE_IO) {
+            getScanProgress(
+                dataDbFile.absolutePath,
+                networkId = networkId
+            )
+        }
+
+    override suspend fun suggestScanRanges(): List<JniScanRange> {
+        return withContext(SdkDispatchers.DATABASE_IO) {
+            suggestScanRanges(
+                dataDbFile.absolutePath,
+                networkId = networkId
+            ).asList()
+        }
+    }
+
+    override suspend fun scanBlocks(fromHeight: Long, limit: Long) {
         return withContext(SdkDispatchers.DATABASE_IO) {
             scanBlocks(
                 fsBlockDbRoot.absolutePath,
                 dataDbFile.absolutePath,
-                limit ?: -1,
+                fromHeight,
+                limit,
                 networkId = networkId
             )
         }
@@ -290,7 +311,7 @@ class RustBackend private constructor(
         to: String,
         value: Long,
         memo: ByteArray?
-    ): Long = withContext(SdkDispatchers.DATABASE_IO) {
+    ): ByteArray = withContext(SdkDispatchers.DATABASE_IO) {
         createToAddress(
             dataDbFile.absolutePath,
             unifiedSpendingKey,
@@ -308,7 +329,7 @@ class RustBackend private constructor(
         account: Int,
         unifiedSpendingKey: ByteArray,
         memo: ByteArray?
-    ): Long {
+    ): ByteArray {
         return withContext(SdkDispatchers.DATABASE_IO) {
             shieldToAddress(
                 dataDbFile.absolutePath,
@@ -403,25 +424,13 @@ class RustBackend private constructor(
         private external fun initDataDb(dbDataPath: String, seed: ByteArray?, networkId: Int): Int
 
         @JvmStatic
-        private external fun initAccountsTableWithKeys(
+        private external fun createAccount(
             dbDataPath: String,
-            ufvks: Array<out String>,
+            seed: ByteArray,
+            treeState: ByteArray,
+            recoverUntil: Long,
             networkId: Int
-        )
-
-        @JvmStatic
-        @Suppress("LongParameterList")
-        private external fun initBlocksTable(
-            dbDataPath: String,
-            height: Long,
-            hash: String,
-            time: Long,
-            saplingTree: String,
-            networkId: Int
-        )
-
-        @JvmStatic
-        private external fun createAccount(dbDataPath: String, seed: ByteArray, networkId: Int): JniUnifiedSpendingKey
+        ): JniUnifiedSpendingKey
 
         @JvmStatic
         private external fun getCurrentAddress(
@@ -439,8 +448,7 @@ class RustBackend private constructor(
         @JvmStatic
         private external fun listTransparentReceivers(dbDataPath: String, account: Int, networkId: Int): Array<String>
 
-        fun validateUnifiedSpendingKey(bytes: ByteArray) =
-            isValidSpendingKey(bytes)
+        fun validateUnifiedSpendingKey(bytes: ByteArray) = isValidSpendingKey(bytes)
 
         @JvmStatic
         private external fun isValidSpendingKey(bytes: ByteArray): Boolean
@@ -465,16 +473,10 @@ class RustBackend private constructor(
         ): Long
 
         @JvmStatic
-        private external fun getReceivedMemoAsUtf8(
+        private external fun getMemoAsUtf8(
             dbDataPath: String,
-            idNote: Long,
-            networkId: Int
-        ): String?
-
-        @JvmStatic
-        private external fun getSentMemoAsUtf8(
-            dbDataPath: String,
-            dNote: Long,
+            txId: ByteArray,
+            outputIndex: Int,
             networkId: Int
         ): String?
 
@@ -485,7 +487,7 @@ class RustBackend private constructor(
         )
 
         @JvmStatic
-        private external fun getLatestHeight(dbCachePath: String): Long
+        private external fun getLatestCacheHeight(dbCachePath: String): Long
 
         @JvmStatic
         private external fun findBlockMetadata(
@@ -499,14 +501,6 @@ class RustBackend private constructor(
             height: Long
         )
 
-        @JvmStatic
-        private external fun validateCombinedChain(
-            dbCachePath: String,
-            dbDataPath: String,
-            limit: Long,
-            networkId: Int
-        ): Long
-
         @JvmStatic
         private external fun getNearestRewindHeight(
             dbDataPath: String,
@@ -521,10 +515,50 @@ class RustBackend private constructor(
             networkId: Int
         )
 
+        @JvmStatic
+        private external fun putSaplingSubtreeRoots(
+            dbDataPath: String,
+            startIndex: Long,
+            roots: Array<JniSubtreeRoot>,
+            networkId: Int
+        )
+
+        @JvmStatic
+        private external fun updateChainTip(
+            dbDataPath: String,
+            height: Long,
+            networkId: Int
+        )
+
+        @JvmStatic
+        private external fun getFullyScannedHeight(
+            dbDataPath: String,
+            networkId: Int
+        ): Long
+
+        @JvmStatic
+        private external fun getMaxScannedHeight(
+            dbDataPath: String,
+            networkId: Int
+        ): Long
+
+        @JvmStatic
+        private external fun getScanProgress(
+            dbDataPath: String,
+            networkId: Int
+        ): JniScanProgress?
+
+        @JvmStatic
+        private external fun suggestScanRanges(
+            dbDataPath: String,
+            networkId: Int
+        ): Array<JniScanRange>
+
         @JvmStatic
         private external fun scanBlocks(
             dbCachePath: String,
             dbDataPath: String,
+            fromHeight: Long,
             limit: Long,
             networkId: Int
         )
@@ -548,7 +582,7 @@ class RustBackend private constructor(
             outputParamsPath: String,
             networkId: Int,
             useZip317Fees: Boolean
-        ): Long
+        ): ByteArray
 
         @JvmStatic
         @Suppress("LongParameterList")
@@ -560,7 +594,7 @@ class RustBackend private constructor(
             outputParamsPath: String,
             networkId: Int,
             useZip317Fees: Boolean
-        ): Long
+        ): ByteArray
 
         @JvmStatic
         private external fun branchIdForHeight(height: Long, networkId: Int): Long
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniBlockMeta.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniBlockMeta.kt
index faf7f324..6dfbe4dd 100644
--- a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniBlockMeta.kt
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniBlockMeta.kt
@@ -1,6 +1,7 @@
 package cash.z.ecc.android.sdk.internal.model
 
 import androidx.annotation.Keep
+import cash.z.ecc.android.sdk.internal.ext.isInUIntRange
 import co.electriccoin.lightwallet.client.model.CompactBlockUnsafe
 
 /**
@@ -23,20 +24,18 @@ class JniBlockMeta(
     init {
         // We require some of the parameters below to be in the range of unsigned integer, because of the Rust layer
         // implementation.
-        require(UINT_RANGE.contains(height)) {
-            "Height $height is outside of allowed range $UINT_RANGE"
+        require(height.isInUIntRange()) {
+            "Height $height is outside of allowed UInt range"
         }
-        require(UINT_RANGE.contains(saplingOutputsCount)) {
-            "SaplingOutputsCount $saplingOutputsCount is outside of allowed range $UINT_RANGE"
+        require(saplingOutputsCount.isInUIntRange()) {
+            "SaplingOutputsCount $saplingOutputsCount is outside of allowed UInt range"
         }
-        require(UINT_RANGE.contains(orchardOutputsCount)) {
-            "SaplingOutputsCount $orchardOutputsCount is outside of allowed range $UINT_RANGE"
+        require(orchardOutputsCount.isInUIntRange()) {
+            "SaplingOutputsCount $orchardOutputsCount is outside of allowed UInt range"
         }
     }
 
     companion object {
-        private val UINT_RANGE = 0.toLong()..UInt.MAX_VALUE.toLong()
-
         fun new(block: CompactBlockUnsafe): JniBlockMeta {
             return JniBlockMeta(
                 height = block.height,
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniScanProgress.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniScanProgress.kt
new file mode 100644
index 00000000..f0fec273
--- /dev/null
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniScanProgress.kt
@@ -0,0 +1,32 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import androidx.annotation.Keep
+
+/**
+ * Serves as cross layer (Kotlin, Rust) communication class.
+ *
+ * @throws IllegalArgumentException unless (numerator is nonnegative, denominator is
+ *         positive, and the represented ratio is in the range 0.0 to 1.0 inclusive).
+ * @param numerator the numerator of the progress ratio
+ * @param denominator the denominator of the progress ratio
+ */
+@Keep
+class JniScanProgress(
+    val numerator: Long,
+    val denominator: Long
+) {
+    init {
+        require(numerator >= 0L) {
+            "Numerator $numerator is outside of allowed range [0, Long.MAX_VALUE]"
+        }
+        require(denominator >= 1L) {
+            "Denominator $denominator is outside of allowed range [1, Long.MAX_VALUE]"
+        }
+        require(numerator.toFloat().div(denominator) >= 0f) {
+            "Result of ${numerator.toFloat()}/$denominator is outside of allowed range"
+        }
+        require(numerator.toFloat().div(denominator) <= 1f) {
+            "Result of ${numerator.toFloat()}/$denominator is outside of allowed range"
+        }
+    }
+}
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniScanRange.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniScanRange.kt
new file mode 100644
index 00000000..640dd173
--- /dev/null
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniScanRange.kt
@@ -0,0 +1,32 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import androidx.annotation.Keep
+import cash.z.ecc.android.sdk.internal.ext.isInUIntRange
+
+/**
+ * Serves as cross layer (Kotlin, Rust) communication class.
+ *
+ * @param startHeight the minimum height in the range (inclusive) - although it's type Long, it needs to be a UInt
+ * @param endHeight the maximum height in the range (exclusive) - although it's type Long, it needs to be a UInt
+ * @param priority the priority of the range for scanning
+ */
+@Keep
+class JniScanRange(
+    val startHeight: Long,
+    val endHeight: Long,
+    val priority: Long
+) {
+    init {
+        // We require some of the parameters below to be in the range of unsigned integer, because of the Rust layer
+        // implementation.
+        require(startHeight.isInUIntRange()) {
+            "Height $startHeight is outside of allowed UInt range"
+        }
+        require(endHeight.isInUIntRange()) {
+            "Height $endHeight is outside of allowed UInt range"
+        }
+        require(endHeight >= startHeight) {
+            "End height $endHeight must be greater than start height $startHeight."
+        }
+    }
+}
diff --git a/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniSubtreeRoot.kt b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniSubtreeRoot.kt
new file mode 100644
index 00000000..9fd50ba9
--- /dev/null
+++ b/backend-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/JniSubtreeRoot.kt
@@ -0,0 +1,34 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import androidx.annotation.Keep
+import cash.z.ecc.android.sdk.internal.ext.isInUIntRange
+
+/**
+ * Serves as cross layer (Kotlin, Rust) communication class.
+ *
+ * @param rootHash the subtree's root hash
+ * @param completingBlockHeight the block height in which the subtree was completed - although it's type Long, it needs
+ * to be in UInt range
+ */
+@Keep
+class JniSubtreeRoot(
+    val rootHash: ByteArray,
+    val completingBlockHeight: Long
+) {
+    init {
+        // We require some of the parameters below to be in the range of unsigned integer,
+        // because of the Rust layer implementation.
+        require(completingBlockHeight.isInUIntRange()) {
+            "Height $completingBlockHeight is outside of allowed UInt range"
+        }
+    }
+
+    companion object {
+        fun new(rootHash: ByteArray, completingBlockHeight: Long): JniSubtreeRoot {
+            return JniSubtreeRoot(
+                rootHash = rootHash,
+                completingBlockHeight = completingBlockHeight
+            )
+        }
+    }
+}
diff --git a/backend-lib/src/main/rust/lib.rs b/backend-lib/src/main/rust/lib.rs
index 283b3dc5..d16a23ff 100644
--- a/backend-lib/src/main/rust/lib.rs
+++ b/backend-lib/src/main/rust/lib.rs
@@ -1,5 +1,5 @@
-use std::collections::HashMap;
 use std::convert::{TryFrom, TryInto};
+use std::num::NonZeroU32;
 use std::panic;
 use std::path::Path;
 use std::ptr;
@@ -11,34 +11,40 @@ use jni::{
     sys::{jboolean, jbyteArray, jint, jlong, jobject, jobjectArray, jstring, JNI_FALSE, JNI_TRUE},
     JNIEnv,
 };
+use prost::Message;
 use schemer::MigratorError;
 use secrecy::{ExposeSecret, SecretVec};
 use tracing::{debug, error};
 use tracing_subscriber::prelude::*;
 use tracing_subscriber::reload;
 use zcash_address::{ToAddress, ZcashAddress};
+use zcash_client_backend::data_api::{
+    scanning::{ScanPriority, ScanRange},
+    AccountBirthday, NoteId, Ratio, ShieldedProtocol,
+};
 use zcash_client_backend::keys::{DecodingError, UnifiedSpendingKey};
 use zcash_client_backend::{
     address::{RecipientAddress, UnifiedAddress},
     data_api::{
-        chain::{self, scan_cached_blocks, validate_chain},
+        chain::{scan_cached_blocks, CommitmentTreeRoot},
         wallet::{
             decrypt_and_store_transaction, input_selection::GreedyInputSelector,
             shield_transparent_funds, spend,
         },
-        WalletRead, WalletWrite,
+        WalletCommitmentTrees, WalletRead, WalletWrite,
     },
     encoding::AddressCodec,
     fees::DustOutputPolicy,
     keys::{Era, UnifiedFullViewingKey},
+    proto::service::TreeState,
     wallet::{OvkPolicy, WalletTransparentOutput},
     zip321::{Payment, TransactionRequest},
 };
 use zcash_client_sqlite::chain::init::init_blockmeta_db;
 use zcash_client_sqlite::{
     chain::BlockMeta,
-    wallet::init::{init_accounts_table, init_blocks_table, init_wallet_db, WalletMigrationError},
-    FsBlockDb, NoteId, WalletDb,
+    wallet::init::{init_wallet_db, WalletMigrationError},
+    FsBlockDb, WalletDb,
 };
 use zcash_primitives::consensus::Network::{MainNetwork, TestNetwork};
 use zcash_primitives::{
@@ -46,9 +52,11 @@ use zcash_primitives::{
     consensus::{BlockHeight, BranchId, Network, Parameters},
     legacy::{Script, TransparentAddress},
     memo::{Memo, MemoBytes},
+    merkle_tree::HashSer,
+    sapling,
     transaction::{
         components::{amount::NonNegativeAmount, Amount, OutPoint, TxOut},
-        Transaction,
+        Transaction, TxId,
     },
     zip32::{AccountId, DiversifierIndex},
 };
@@ -68,7 +76,8 @@ mod zip317 {
     pub(super) use zcash_primitives::transaction::fees::zip317::*;
 }
 
-const ANCHOR_OFFSET: u32 = 10;
+const ANCHOR_OFFSET_U32: u32 = 10;
+const ANCHOR_OFFSET: NonZeroU32 = unsafe { NonZeroU32::new_unchecked(ANCHOR_OFFSET_U32) };
 
 #[cfg(debug_assertions)]
 fn print_debug_state() {
@@ -84,7 +93,7 @@ fn wallet_db<P: Parameters>(
     env: &JNIEnv<'_>,
     params: P,
     db_data: JString<'_>,
-) -> Result<WalletDb<P>, failure::Error> {
+) -> Result<WalletDb<rusqlite::Connection, P>, failure::Error> {
     WalletDb::for_path(utils::java_string_to_rust(&env, db_data), params)
         .map_err(|e| format_err!("Error opening wallet database connection: {}", e))
 }
@@ -252,16 +261,32 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_cr
     _: JClass<'_>,
     db_data: JString<'_>,
     seed: jbyteArray,
+    treestate: jbyteArray,
+    recover_until: jlong,
     network_id: jint,
 ) -> jobject {
+    use zcash_client_backend::data_api::BirthdayError;
+
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
         let seed = SecretVec::new(env.convert_byte_array(seed).unwrap());
+        let treestate = TreeState::decode(&env.convert_byte_array(treestate).unwrap()[..])
+            .map_err(|e| format_err!("Invalid TreeState: {}", e))?;
+        let recover_until = recover_until.try_into().ok();
 
-        let mut db_ops = db_data.get_update_ops()?;
-        let (account, usk) = db_ops
-            .create_account(&seed)
+        let birthday =
+            AccountBirthday::from_treestate(treestate, recover_until).map_err(|e| match e {
+                BirthdayError::HeightInvalid(e) => {
+                    format_err!("Invalid TreeState: Invalid height: {}", e)
+                }
+                BirthdayError::Decode(e) => {
+                    format_err!("Invalid TreeState: Invalid frontier encoding: {}", e)
+                }
+            })?;
+
+        let (account, usk) = db_data
+            .create_account(&seed, birthday)
             .map_err(|e| format_err!("Error while initializing accounts: {}", e))?;
 
         encode_usk(&env, account, usk)
@@ -269,52 +294,6 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_cr
     unwrap_exc_or(&env, res, ptr::null_mut())
 }
 
-/// Initialises the data database with the given set of unified full viewing keys.
-///
-/// This should only be used in special cases for implementing wallet recovery; prefer
-/// `RustBackend.createAccount` for normal account creation purposes.
-#[no_mangle]
-pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_initAccountsTableWithKeys(
-    env: JNIEnv<'_>,
-    _: JClass<'_>,
-    db_data: JString<'_>,
-    ufvks_arr: jobjectArray,
-    network_id: jint,
-) -> jboolean {
-    let res = panic::catch_unwind(|| {
-        let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        // TODO: avoid all this unwrapping and also surface errors, better
-        let count = env.get_array_length(ufvks_arr).unwrap();
-        let ufvks = (0..count)
-            .map(|i| env.get_object_array_element(ufvks_arr, i))
-            .map(|jstr| utils::java_string_to_rust(&env, jstr.unwrap().into()))
-            .map(|ufvkstr| {
-                UnifiedFullViewingKey::decode(&network, &ufvkstr).map_err(|e| {
-                    if e.starts_with("UFVK is for network") {
-                            let (network_name, other) = if network == TestNetwork {
-                                ("testnet", "mainnet")
-                            } else {
-                                ("mainnet", "testnet")
-                            };
-                            format_err!("Error: Wrong network! Unable to decode viewing key for {}. Check whether this is a key for {}.", network_name, other)
-                    } else {
-                        format_err!("Invalid Unified Full Viewing Key: {}", e)
-                    }
-                })
-            })
-            .enumerate() // TODO: Pass account IDs across the FFI.
-            .map(|(i, res)| res.map(|ufvk| (AccountId::from(i as u32), ufvk)))
-            .collect::<Result<HashMap<_,_>, _>>()?;
-
-        match init_accounts_table(&db_data, &ufvks) {
-            Ok(()) => Ok(JNI_TRUE),
-            Err(e) => Err(format_err!("Error while initializing accounts: {}", e)),
-        }
-    });
-    unwrap_exc_or(&env, res, JNI_FALSE)
-}
-
 /// Derives and returns a unified spending key from the given seed for the given account ID.
 ///
 /// Returns the newly created [ZIP 316] account identifier, along with the binary encoding
@@ -472,48 +451,6 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustDerivation
     unwrap_exc_or(&env, res, ptr::null_mut())
 }
 
-#[no_mangle]
-pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_initBlocksTable(
-    env: JNIEnv<'_>,
-    _: JClass<'_>,
-    db_data: JString<'_>,
-    height: jlong,
-    hash_string: JString<'_>,
-    time: jlong,
-    sapling_tree_string: JString<'_>,
-    network_id: jint,
-) -> jboolean {
-    let res = panic::catch_unwind(|| {
-        let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let hash = {
-            let mut hash = hex::decode(utils::java_string_to_rust(&env, hash_string)).unwrap();
-            hash.reverse();
-            BlockHash::from_slice(&hash)
-        };
-        let time = if time >= 0 && time <= jlong::from(u32::max_value()) {
-            time as u32
-        } else {
-            return Err(format_err!("time argument must fit in a u32"));
-        };
-        let sapling_tree =
-            hex::decode(utils::java_string_to_rust(&env, sapling_tree_string)).unwrap();
-
-        debug!("initializing blocks table with height {}", height);
-        match init_blocks_table(
-            &db_data,
-            (height as u32).try_into()?,
-            hash,
-            time,
-            &sapling_tree,
-        ) {
-            Ok(()) => Ok(JNI_TRUE),
-            Err(e) => Err(format_err!("Error while initializing blocks table: {}", e)),
-        }
-    });
-    unwrap_exc_or(&env, res, JNI_FALSE)
-}
-
 #[no_mangle]
 pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getCurrentAddress(
     env: JNIEnv<'_>,
@@ -720,27 +657,20 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_ge
         let db_data = wallet_db(&env, network, db_data)?;
         let account = AccountId::from(u32::try_from(accountj)?);
 
-        // We query the unverified balance including unmined transactions. Shielded notes
-        // in unmined transactions are never spendable, but this ensures that the balance
-        // reported to users does not drop temporarily in a way that they don't expect.
-        // `getVerifiedBalance` requires `ANCHOR_OFFSET` confirmations, which means it
-        // always shows a spendable balance.
-        let min_confirmations = 0;
-
-        (&db_data)
-            .get_target_and_anchor_heights(min_confirmations)
-            .map_err(|e| format_err!("Error while fetching anchor height: {}", e))
-            .and_then(|opt_anchor| {
-                opt_anchor
-                    .map(|(_, a)| a)
-                    .ok_or(format_err!("Anchor height not available; scan required."))
-            })
-            .and_then(|anchor| {
-                (&db_data)
-                    .get_balance_at(account, anchor)
-                    .map_err(|e| format_err!("Error while fetching verified balance: {}", e))
-            })
-            .map(|amount| amount.into())
+        if let Some(wallet_summary) = db_data
+            .get_wallet_summary(0)
+            .map_err(|e| format_err!("Error while fetching balance: {}", e))?
+        {
+            wallet_summary
+                .account_balances()
+                .get(&account)
+                .ok_or_else(|| format_err!("Unknown account"))
+                .map(|balances| Amount::from(balances.sapling_balance.total()).into())
+        } else {
+            // `None` means that the caller has not yet called `updateChainTip` on a
+            // brand-new wallet, so we can assume the balance is zero.
+            Ok(0)
+        }
     });
     unwrap_exc_or(&env, res, -1)
 }
@@ -797,16 +727,14 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_ge
         let addr = utils::java_string_to_rust(&env, address);
         let taddr = TransparentAddress::decode(&network, &addr).unwrap();
 
-        // We select all transparent funds including unmined coins, as that is the same
-        // set of UTXOs we shield from.
-        let min_confirmations = 0;
+        let min_confirmations = NonZeroU32::new(1).unwrap();
 
         let amount = (&db_data)
             .get_target_and_anchor_heights(min_confirmations)
             .map_err(|e| format_err!("Error while fetching anchor height: {}", e))
             .and_then(|opt_anchor| {
                 opt_anchor
-                    .map(|(_, a)| a)
+                    .map(|(target, _)| target) // Include unconfirmed funds.
                     .ok_or(format_err!("Anchor height not available; scan required."))
             })
             .and_then(|anchor| {
@@ -838,70 +766,49 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_ge
         let db_data = wallet_db(&env, network, db_data)?;
         let account = AccountId::from(u32::try_from(account)?);
 
-        (&db_data)
-            .get_target_and_anchor_heights(ANCHOR_OFFSET)
-            .map_err(|e| format_err!("Error while fetching anchor height: {}", e))
-            .and_then(|opt_anchor| {
-                opt_anchor
-                    .map(|(_, a)| a)
-                    .ok_or(format_err!("Anchor height not available; scan required."))
-            })
-            .and_then(|anchor| {
-                (&db_data)
-                    .get_balance_at(account, anchor)
-                    .map_err(|e| format_err!("Error while fetching verified balance: {}", e))
-            })
-            .map(|amount| amount.into())
+        if let Some(wallet_summary) = db_data
+            .get_wallet_summary(ANCHOR_OFFSET_U32)
+            .map_err(|e| format_err!("Error while fetching verified balance: {}", e))?
+        {
+            wallet_summary
+                .account_balances()
+                .get(&account)
+                .ok_or_else(|| format_err!("Unknown account"))
+                .map(|balances| Amount::from(balances.sapling_balance.spendable_value).into())
+        } else {
+            // `None` means that the caller has not yet called `updateChainTip` on a
+            // brand-new wallet, so we can assume the balance is zero.
+            Ok(0)
+        }
     });
 
     unwrap_exc_or(&env, res, -1)
 }
 
 #[no_mangle]
-pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getReceivedMemoAsUtf8(
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getMemoAsUtf8(
     env: JNIEnv<'_>,
     _: JClass<'_>,
     db_data: JString<'_>,
-    id_note: jlong,
+    txid_bytes: jbyteArray,
+    output_index: jint,
     network_id: jint,
 ) -> jstring {
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
         let db_data = wallet_db(&env, network, db_data)?;
 
-        let memo = (&db_data)
-            .get_memo(NoteId::ReceivedNoteId(id_note))
-            .map_err(|e| format_err!("An error occurred retrieving the memo, {}", e))
-            .and_then(|memo| match memo {
-                Memo::Empty => Ok("".to_string()),
-                Memo::Text(memo) => Ok(memo.into()),
-                _ => Err(format_err!("This memo does not contain UTF-8 text")),
-            })?;
-
-        let output = env.new_string(memo).expect("Couldn't create Java string!");
-        Ok(output.into_raw())
-    });
-    unwrap_exc_or(&env, res, ptr::null_mut())
-}
-
-#[no_mangle]
-pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getSentMemoAsUtf8(
-    env: JNIEnv<'_>,
-    _: JClass<'_>,
-    db_data: JString<'_>,
-    id_note: jlong,
-    network_id: jint,
-) -> jstring {
-    let res = panic::catch_unwind(|| {
-        let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
+        let txid_bytes = env.convert_byte_array(txid_bytes)?;
+        let txid = TxId::read(&txid_bytes[..])?;
+        let output_index = u16::try_from(output_index)?;
 
         let memo = (&db_data)
-            .get_memo(NoteId::SentNoteId(id_note))
+            .get_memo(NoteId::new(txid, ShieldedProtocol::Sapling, output_index))
             .map_err(|e| format_err!("An error occurred retrieving the memo, {}", e))
             .and_then(|memo| match memo {
-                Memo::Empty => Ok("".to_string()),
-                Memo::Text(memo) => Ok(memo.into()),
+                Some(Memo::Empty) => Ok("".to_string()),
+                Some(Memo::Text(memo)) => Ok(memo.into()),
+                None => Err(format_err!("Memo not available")),
                 _ => Err(format_err!("This memo does not contain UTF-8 text")),
             })?;
 
@@ -984,7 +891,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_wr
 }
 
 #[no_mangle]
-pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getLatestHeight(
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getLatestCacheHeight(
     env: JNIEnv<'_>,
     _: JClass<'_>,
     fsblockdb_root: JString<'_>,
@@ -1051,44 +958,6 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_re
     unwrap_exc_or(&env, res, ())
 }
 
-#[no_mangle]
-pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_validateCombinedChain(
-    env: JNIEnv<'_>,
-    _: JClass<'_>,
-    db_cache: JString<'_>,
-    db_data: JString<'_>,
-    limit: jlong,
-    network_id: jint,
-) -> jlong {
-    let res = panic::catch_unwind(|| {
-        let network = parse_network(network_id as u32)?;
-        let block_db = block_db(&env, db_cache)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let validate_limit = u32::try_from(limit).ok();
-
-        let validate_from = (&db_data)
-            .get_max_height_hash()
-            .map_err(|e| format_err!("Error while validating chain: {}", e))?;
-
-        let val_res = validate_chain(&block_db, validate_from, validate_limit);
-
-        if let Err(e) = val_res {
-            match e {
-                chain::error::Error::Chain(e) => {
-                    let upper_bound_u32 = u32::from(e.at_height());
-                    Ok(upper_bound_u32 as i64)
-                }
-                _ => Err(format_err!("Error while validating chain: {:?}", e)),
-            }
-        } else {
-            // All blocks are valid, so "highest invalid block height" is below genesis.
-            Ok(-1)
-        }
-    });
-
-    unwrap_exc_or(&env, res, 0) as jlong
-}
-
 #[no_mangle]
 pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getNearestRewindHeight(
     env: JNIEnv<'_>,
@@ -1135,8 +1004,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_re
 ) -> jboolean {
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let mut db_data = db_data.get_update_ops()?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
 
         let height = BlockHeight::try_from(height)?;
         db_data
@@ -1148,23 +1016,247 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_re
     unwrap_exc_or(&env, res, JNI_FALSE)
 }
 
+fn decode_sapling_subtree_root(
+    env: &JNIEnv<'_>,
+    obj: JObject<'_>,
+) -> Result<CommitmentTreeRoot<sapling::Node>, failure::Error> {
+    let long_as_u32 = |name| -> Result<u32, failure::Error> {
+        Ok(u32::try_from(env.get_field(obj, name, "J")?.j()?)?)
+    };
+
+    fn byte_array(
+        env: &JNIEnv<'_>,
+        obj: JObject<'_>,
+        name: &str,
+    ) -> Result<Vec<u8>, failure::Error> {
+        let field = env.get_field(obj, name, "[B")?.l()?.into_raw();
+        Ok(env.convert_byte_array(field)?[..].try_into()?)
+    }
+
+    Ok(CommitmentTreeRoot::from_parts(
+        BlockHeight::from_u32(long_as_u32("completingBlockHeight")?),
+        sapling::Node::read(&byte_array(env, obj, "rootHash")?[..])?,
+    ))
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_putSaplingSubtreeRoots(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    start_index: jlong,
+    roots: jobjectArray,
+    network_id: jint,
+) -> jboolean {
+    let res = panic::catch_unwind(|| {
+        let network = parse_network(network_id as u32)?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
+
+        let start_index = if start_index >= 0 {
+            start_index as u64
+        } else {
+            return Err(format_err!("Start index must be nonnegative."));
+        };
+        let roots = {
+            let count = env.get_array_length(roots).unwrap();
+            (0..count)
+                .map(|i| {
+                    env.get_object_array_element(roots, i)
+                        .map_err(|e| e.into())
+                        .and_then(|jobj| decode_sapling_subtree_root(&env, jobj))
+                })
+                .collect::<Result<Vec<_>, _>>()?
+        };
+
+        db_data
+            .put_sapling_subtree_roots(start_index, &roots)
+            .map(|()| JNI_TRUE)
+            .map_err(|e| format_err!("Error while storing Sapling subtree roots: {}", e))
+    });
+
+    unwrap_exc_or(&env, res, JNI_FALSE)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_updateChainTip(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    height: jlong,
+    network_id: jint,
+) -> jboolean {
+    let res = panic::catch_unwind(|| {
+        let network = parse_network(network_id as u32)?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
+        let height = BlockHeight::try_from(height)?;
+
+        db_data
+            .update_chain_tip(height)
+            .map(|()| JNI_TRUE)
+            .map_err(|e| format_err!("Error while updating chain tip to height {}: {}", height, e))
+    });
+
+    unwrap_exc_or(&env, res, JNI_FALSE)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getFullyScannedHeight(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    network_id: jint,
+) -> jlong {
+    let res = panic::catch_unwind(|| {
+        let network = parse_network(network_id as u32)?;
+        let db_data = wallet_db(&env, network, db_data)?;
+
+        match db_data.block_fully_scanned() {
+            Ok(Some(metadata)) => Ok(i64::from(u32::from(metadata.block_height()))),
+            // Use -1 to return null across the FFI.
+            Ok(None) => Ok(-1),
+            Err(e) => Err(format_err!(
+                "Failed to read block metadata from WalletDb: {:?}",
+                e
+            )),
+        }
+    });
+    unwrap_exc_or(&env, res, -1)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getMaxScannedHeight(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    network_id: jint,
+) -> jlong {
+    let res = panic::catch_unwind(|| {
+        let network = parse_network(network_id as u32)?;
+        let db_data = wallet_db(&env, network, db_data)?;
+
+        match db_data.block_max_scanned() {
+            Ok(Some(metadata)) => Ok(i64::from(u32::from(metadata.block_height()))),
+            // Use -1 to return null across the FFI.
+            Ok(None) => Ok(-1),
+            Err(e) => Err(format_err!(
+                "Failed to read block metadata from WalletDb: {:?}",
+                e
+            )),
+        }
+    });
+    unwrap_exc_or(&env, res, -1)
+}
+
+/// Returns a `JniScanProgress` object, provided that numerator is nonnegative, denominator
+/// is positive, and the represented ratio is in the range 0.0 to 1.0 inclusive.
+fn encode_scan_progress(env: &JNIEnv<'_>, progress: Ratio<u64>) -> Result<jobject, failure::Error> {
+    let output = env.new_object(
+        "cash/z/ecc/android/sdk/internal/model/JniScanProgress",
+        "(JJ)V",
+        &[
+            JValue::Long(*progress.numerator() as i64),
+            JValue::Long(*progress.denominator() as i64),
+        ],
+    )?;
+    Ok(output.into_raw())
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_getScanProgress(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    network_id: jint,
+) -> jobject {
+    let res = panic::catch_unwind(|| {
+        let network = parse_network(network_id as u32)?;
+        let db_data = wallet_db(&env, network, db_data)?;
+
+        match db_data
+            .get_wallet_summary(0)
+            .map_err(|e| format_err!("Error while fetching scan progress: {}", e))?
+            .and_then(|summary| summary.scan_progress().filter(|r| r.denominator() > &0))
+        {
+            Some(progress) => encode_scan_progress(&env, progress),
+            None => Ok(ptr::null_mut()),
+        }
+    });
+    unwrap_exc_or(&env, res, ptr::null_mut())
+}
+
+fn encode_scan_range<'a>(
+    env: &JNIEnv<'a>,
+    scan_range: ScanRange,
+) -> jni::errors::Result<JObject<'a>> {
+    let priority = match scan_range.priority() {
+        ScanPriority::Ignored => 0,
+        ScanPriority::Scanned => 10,
+        ScanPriority::Historic => 20,
+        ScanPriority::OpenAdjacent => 30,
+        ScanPriority::FoundNote => 40,
+        ScanPriority::ChainTip => 50,
+        ScanPriority::Verify => 60,
+    };
+    env.new_object(
+        "cash/z/ecc/android/sdk/internal/model/JniScanRange",
+        "(JJJ)V",
+        &[
+            JValue::Long(i64::from(u32::from(scan_range.block_range().start))),
+            JValue::Long(i64::from(u32::from(scan_range.block_range().end))),
+            JValue::Long(priority),
+        ],
+    )
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_suggestScanRanges(
+    env: JNIEnv<'_>,
+    _: JClass<'_>,
+    db_data: JString<'_>,
+    network_id: jint,
+) -> jobjectArray {
+    let res = panic::catch_unwind(|| {
+        let network = parse_network(network_id as u32)?;
+        let db_data = wallet_db(&env, network, db_data)?;
+
+        let ranges = db_data
+            .suggest_scan_ranges()
+            .map_err(|e| format_err!("Error while fetching suggested scan ranges: {}", e))?;
+
+        Ok(utils::rust_vec_to_java(
+            &env,
+            ranges,
+            "cash/z/ecc/android/sdk/internal/model/JniScanRange",
+            |env, scan_range| encode_scan_range(env, scan_range),
+            |env| {
+                encode_scan_range(
+                    env,
+                    ScanRange::from_parts((0.into())..(0.into()), ScanPriority::Scanned),
+                )
+            },
+        ))
+    });
+    unwrap_exc_or(&env, res, ptr::null_mut())
+}
+
 #[no_mangle]
 pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_scanBlocks(
     env: JNIEnv<'_>,
     _: JClass<'_>,
     db_cache: JString<'_>,
     db_data: JString<'_>,
+    from_height: jlong,
     limit: jlong,
     network_id: jint,
 ) -> jboolean {
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
         let db_cache = block_db(&env, db_cache)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let mut db_data = db_data.get_update_ops()?;
-        let limit = u32::try_from(limit).ok();
+        let mut db_data = wallet_db(&env, network, db_data)?;
+        let from_height = BlockHeight::try_from(from_height)?;
+        let limit = usize::try_from(limit)?;
 
-        match scan_cached_blocks(&network, &db_cache, &mut db_data, limit) {
+        match scan_cached_blocks(&network, &db_cache, &mut db_data, from_height, limit) {
             Ok(()) => Ok(JNI_TRUE),
             Err(e) => Err(format_err!(
                 "Rust error while scanning blocks (limit {:?}): {:?}",
@@ -1199,8 +1291,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_pu
         txid.copy_from_slice(&txid_bytes);
 
         let script_pubkey = Script(env.convert_byte_array(script).unwrap());
-        let db_data = wallet_db(&env, network, db_data)?;
-        let mut db_data = db_data.get_update_ops()?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
         let addr = utils::java_string_to_rust(&env, address);
         let _address = TransparentAddress::decode(&network, &addr).unwrap();
 
@@ -1233,8 +1324,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_de
 ) -> jboolean {
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let mut db_data = db_data.get_update_ops()?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
         let tx_bytes = env.convert_byte_array(tx).unwrap();
         // The consensus branch ID passed in here does not matter:
         // - v4 and below cache it internally, but all we do with this transaction while
@@ -1289,11 +1379,10 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_cr
     output_params: JString<'_>,
     network_id: jint,
     use_zip317_fees: jboolean,
-) -> jlong {
+) -> jbyteArray {
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let mut db_data = db_data.get_update_ops()?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
         let usk = decode_usk(&env, usk)?;
         let to = utils::java_string_to_rust(&env, to);
         let value =
@@ -1334,7 +1423,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_cr
         }])
         .map_err(|e| format_err!("Error creating transaction request: {:?}", e))?;
 
-        zip317_helper(
+        let txid = zip317_helper(
             (&mut db_data, prover, request),
             use_zip317_fees,
             |(wallet_db, prover, request), input_selector| {
@@ -1363,9 +1452,11 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_cr
                 )
                 .map_err(|e| format_err!("Error while creating transaction: {}", e))
             },
-        )
+        )?;
+
+        utils::rust_bytes_to_java(&env, txid.as_ref())
     });
-    unwrap_exc_or(&env, res, -1)
+    unwrap_exc_or(&env, res, ptr::null_mut())
 }
 
 #[no_mangle]
@@ -1379,17 +1470,16 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_sh
     output_params: JString<'_>,
     network_id: jint,
     use_zip317_fees: jboolean,
-) -> jlong {
+) -> jbyteArray {
     let res = panic::catch_unwind(|| {
         let network = parse_network(network_id as u32)?;
-        let db_data = wallet_db(&env, network, db_data)?;
-        let mut db_data = db_data.get_update_ops()?;
+        let mut db_data = wallet_db(&env, network, db_data)?;
         let usk = decode_usk(&env, usk)?;
         let memo_bytes = env.convert_byte_array(memo).unwrap();
         let spend_params = utils::java_string_to_rust(&env, spend_params);
         let output_params = utils::java_string_to_rust(&env, output_params);
 
-        let min_confirmations = 0;
+        let min_confirmations = NonZeroU32::new(1).unwrap();
 
         let account = db_data
             .get_account_for_ufvk(&usk.to_unified_full_viewing_key())?
@@ -1400,7 +1490,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_sh
             .map_err(|e| format_err!("Error while fetching anchor height: {}", e))
             .and_then(|opt_anchor| {
                 opt_anchor
-                    .map(|(_, a)| a)
+                    .map(|(target, _)| target) // Include unconfirmed funds.
                     .ok_or(format_err!("Anchor height not available; scan required."))
             })
             .and_then(|anchor| {
@@ -1423,7 +1513,7 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_sh
 
         let shielding_threshold = NonNegativeAmount::from_u64(100000).unwrap();
 
-        zip317_helper(
+        let txid = zip317_helper(
             (&mut db_data, prover),
             use_zip317_fees,
             |(wallet_db, prover), input_selector| {
@@ -1454,9 +1544,11 @@ pub unsafe extern "C" fn Java_cash_z_ecc_android_sdk_internal_jni_RustBackend_sh
                 )
                 .map_err(|e| format_err!("Error while shielding transaction: {}", e))
             },
-        )
+        )?;
+
+        utils::rust_bytes_to_java(&env, txid.as_ref())
     });
-    unwrap_exc_or(&env, res, -1)
+    unwrap_exc_or(&env, res, ptr::null_mut())
 }
 
 #[no_mangle]
diff --git a/backend-lib/src/main/rust/utils.rs b/backend-lib/src/main/rust/utils.rs
index 70068f25..584f7d3e 100644
--- a/backend-lib/src/main/rust/utils.rs
+++ b/backend-lib/src/main/rust/utils.rs
@@ -1,13 +1,13 @@
+use core::slice;
+
 use jni::{
     descriptors::Desc,
     errors::Result as JNIResult,
     objects::{JClass, JObject, JString},
-    sys::{jobjectArray, jsize},
+    sys::{jbyteArray, jobjectArray, jsize},
     JNIEnv,
 };
 
-use std::ops::Deref;
-
 pub(crate) mod exception;
 pub(crate) mod target_ndk;
 pub(crate) mod trace;
@@ -18,6 +18,17 @@ pub(crate) fn java_string_to_rust(env: &JNIEnv<'_>, jstring: JString<'_>) -> Str
         .into()
 }
 
+pub(crate) fn rust_bytes_to_java(
+    env: &JNIEnv<'_>,
+    data: &[u8],
+) -> Result<jbyteArray, failure::Error> {
+    // SAFETY: jbyte (i8) has the same size and alignment as u8.
+    let buf = unsafe { slice::from_raw_parts(data.as_ptr().cast(), data.len()) };
+    let jret = env.new_byte_array(data.len() as jsize)?;
+    env.set_byte_array_region(jret, 0, buf)?;
+    Ok(jret)
+}
+
 pub(crate) fn rust_vec_to_java<'a, T, U, V, F, G>(
     env: &JNIEnv<'a>,
     data: Vec<T>,
@@ -27,17 +38,17 @@ pub(crate) fn rust_vec_to_java<'a, T, U, V, F, G>(
 ) -> jobjectArray
 where
     U: Desc<'a, JClass<'a>>,
-    V: Deref<Target = JObject<'a>>,
+    V: Into<JObject<'a>>,
     F: Fn(&JNIEnv<'a>, T) -> JNIResult<V>,
     G: Fn(&JNIEnv<'a>) -> JNIResult<V>,
 {
     let jempty = empty_element(env).expect("Couldn't create Java string!");
     let jret = env
-        .new_object_array(data.len() as jsize, element_class, *jempty)
+        .new_object_array(data.len() as jsize, element_class, jempty.into())
         .expect("Couldn't create Java array!");
     for (i, elem) in data.into_iter().enumerate() {
         let jelem = element_map(env, elem).expect("Couldn't map element to Java!");
-        env.set_object_array_element(jret, i as jsize, *jelem)
+        env.set_object_array_element(jret, i as jsize, jelem.into())
             .expect("Couldn't set Java array element!");
     }
     jret
diff --git a/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/ext/NumberExtTest.kt b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/ext/NumberExtTest.kt
new file mode 100644
index 00000000..44d2ae68
--- /dev/null
+++ b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/ext/NumberExtTest.kt
@@ -0,0 +1,24 @@
+package cash.z.ecc.android.sdk.internal.ext
+
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class NumberExtTest {
+    @Test
+    fun is_in_range_test() {
+        assertTrue(1L.isInUIntRange())
+        assertTrue(0L.isInUIntRange())
+        assertTrue(UInt.MAX_VALUE.toLong().isInUIntRange())
+        assertTrue(UInt.MIN_VALUE.toLong().isInUIntRange())
+    }
+
+    @Test
+    fun is_not_in_range_test() {
+        assertFalse(0L.minus(1L).isInUIntRange())
+        assertFalse(Long.MAX_VALUE.isInUIntRange())
+        assertFalse(Long.MIN_VALUE.isInUIntRange())
+        assertFalse(UInt.MAX_VALUE.toLong().plus(1L).isInUIntRange())
+        assertFalse(UInt.MIN_VALUE.toLong().minus(1L).isInUIntRange())
+    }
+}
diff --git a/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniBlockMetaTest.kt b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniBlockMetaTest.kt
new file mode 100644
index 00000000..8194c06a
--- /dev/null
+++ b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniBlockMetaTest.kt
@@ -0,0 +1,32 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+import kotlin.test.assertIs
+
+class JniBlockMetaTest {
+    @Test
+    fun attributes_within_constraints() {
+        val instance = JniBlockMeta(
+            height = UInt.MAX_VALUE.toLong(),
+            hash = byteArrayOf(),
+            time = 0L,
+            saplingOutputsCount = UInt.MIN_VALUE.toLong(),
+            orchardOutputsCount = UInt.MIN_VALUE.toLong()
+        )
+        assertIs<JniBlockMeta>(instance)
+    }
+
+    @Test
+    fun attributes_not_in_constraints() {
+        assertFailsWith(IllegalArgumentException::class) {
+            JniBlockMeta(
+                height = Long.MAX_VALUE,
+                hash = byteArrayOf(),
+                time = 0L,
+                saplingOutputsCount = Long.MIN_VALUE,
+                orchardOutputsCount = Long.MIN_VALUE
+            )
+        }
+    }
+}
diff --git a/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniScanRangeTest.kt b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniScanRangeTest.kt
new file mode 100644
index 00000000..ada935b5
--- /dev/null
+++ b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniScanRangeTest.kt
@@ -0,0 +1,28 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+import kotlin.test.assertIs
+
+class JniScanRangeTest {
+    @Test
+    fun attributes_within_constraints() {
+        val instance = JniScanRange(
+            startHeight = UInt.MIN_VALUE.toLong(),
+            endHeight = UInt.MAX_VALUE.toLong(),
+            priority = 10
+        )
+        assertIs<JniScanRange>(instance)
+    }
+
+    @Test
+    fun attributes_not_in_constraints() {
+        assertFailsWith(IllegalArgumentException::class) {
+            JniScanRange(
+                startHeight = Long.MIN_VALUE,
+                endHeight = Long.MAX_VALUE,
+                priority = 10
+            )
+        }
+    }
+}
diff --git a/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniSubtreeRootTest.kt b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniSubtreeRootTest.kt
new file mode 100644
index 00000000..a9690f6d
--- /dev/null
+++ b/backend-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/JniSubtreeRootTest.kt
@@ -0,0 +1,26 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+import kotlin.test.assertIs
+
+class JniSubtreeRootTest {
+    @Test
+    fun attributes_within_constraints() {
+        val instance = JniSubtreeRoot(
+            rootHash = byteArrayOf(),
+            completingBlockHeight = UInt.MAX_VALUE.toLong()
+        )
+        assertIs<JniSubtreeRoot>(instance)
+    }
+
+    @Test
+    fun attributes_not_in_constraints() {
+        assertFailsWith(IllegalArgumentException::class) {
+            JniSubtreeRoot(
+                rootHash = byteArrayOf(),
+                completingBlockHeight = Long.MAX_VALUE
+            )
+        }
+    }
+}
diff --git a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/TransparentIntegrationTest.kt b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/TransparentIntegrationTest.kt
index 0c58b536..b25021a8 100644
--- a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/TransparentIntegrationTest.kt
+++ b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/TransparentIntegrationTest.kt
@@ -10,11 +10,13 @@ import org.junit.runner.RunWith
 /**
  * Integration test to run in order to catch any regressions in transparent behavior.
  */
+// TODO [#1224]: Refactor and re-enable disabled darkside tests
+// TODO [#1224]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1224
 @RunWith(AndroidJUnit4::class)
 class TransparentIntegrationTest : DarksideTest() {
     @Before
     fun setup() = runOnce {
-        sithLord.await()
+        // sithLord.await()
     }
 
     @Test
diff --git a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/InboundTxTests.kt b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/InboundTxTests.kt
index 8e0e136c..4f014e1a 100644
--- a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/InboundTxTests.kt
+++ b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/InboundTxTests.kt
@@ -6,15 +6,19 @@ import cash.z.ecc.android.sdk.darkside.test.ScopedTest
 import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.ZcashNetwork
 import org.junit.BeforeClass
+import org.junit.Ignore
 import org.junit.Test
 import org.junit.runner.RunWith
 
+// TODO [#1224]: Refactor and re-enable disabled darkside tests
+// TODO [#1224]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1224
 @RunWith(AndroidJUnit4::class)
 class InboundTxTests : ScopedTest() {
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testTargetBlock_synced() {
-        validator.validateMinHeightSynced(firstBlock)
+        // validator.validateMinHeightSynced(firstBlock)
     }
 
     @Test
@@ -28,10 +32,11 @@ class InboundTxTests : ScopedTest() {
     }
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testTxCountAfter() {
         // add 2 transactions to block 663188 and 'mine' that block
         addTransactions(targetTxBlock, tx663174, tx663188)
-        sithLord.await(timeout = 30_000L, targetHeight = targetTxBlock)
+        // sithLord.await(timeout = 30_000L, targetHeight = targetTxBlock)
         validator.validateTxCount(2)
     }
 
@@ -91,7 +96,7 @@ class InboundTxTests : ScopedTest() {
                 .stageEmptyBlocks(firstBlock + 1, 100)
                 .applyTipHeight(BlockHeight.new(ZcashNetwork.Mainnet, targetTxBlock.value - 1))
 
-            sithLord.await()
+            // sithLord.await()
         }
     }
 }
diff --git a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSetupTest.kt b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSetupTest.kt
index 0d1334c1..f4e82721 100644
--- a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSetupTest.kt
+++ b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSetupTest.kt
@@ -3,34 +3,39 @@ package cash.z.ecc.android.sdk.darkside.reorgs
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import cash.z.ecc.android.sdk.darkside.test.DarksideTestCoordinator
 import cash.z.ecc.android.sdk.darkside.test.ScopedTest
-import cash.z.ecc.android.sdk.model.BlockHeight
-import cash.z.ecc.android.sdk.model.ZcashNetwork
 import org.junit.Before
 import org.junit.BeforeClass
+import org.junit.Ignore
 import org.junit.Test
 import org.junit.runner.RunWith
 
+// TODO [#1224]: Refactor and re-enable disabled darkside tests
+// TODO [#1224]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1224
 @RunWith(AndroidJUnit4::class)
 class ReorgSetupTest : ScopedTest() {
 
+    /*
     private val birthdayHeight = BlockHeight.new(ZcashNetwork.Mainnet, 663150)
     private val targetHeight = BlockHeight.new(ZcashNetwork.Mainnet, 663250)
+     */
 
     @Before
     fun setup() {
-        sithLord.await()
+        // sithLord.await()
     }
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testBeforeReorg_minHeight() = timeout(30_000L) {
         // validate that we are synced, at least to the birthday height
-        validator.validateMinHeightSynced(birthdayHeight)
+        // validator.validateMinHeightSynced(birthdayHeight)
     }
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testBeforeReorg_maxHeight() = timeout(30_000L) {
         // validate that we are not synced beyond the target height
-        validator.validateMaxHeightSynced(targetHeight)
+        // validator.validateMaxHeightSynced(targetHeight)
     }
 
     companion object {
diff --git a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSmallTest.kt b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSmallTest.kt
index 3de23724..bf58e840 100644
--- a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSmallTest.kt
+++ b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/reorgs/ReorgSmallTest.kt
@@ -3,45 +3,49 @@ package cash.z.ecc.android.sdk.darkside.reorgs
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import cash.z.ecc.android.sdk.darkside.test.DarksideTestCoordinator
 import cash.z.ecc.android.sdk.darkside.test.ScopedTest
-import cash.z.ecc.android.sdk.model.BlockHeight
-import cash.z.ecc.android.sdk.model.ZcashNetwork
 import org.junit.Assert.assertTrue
 import org.junit.Before
 import org.junit.BeforeClass
+import org.junit.Ignore
 import org.junit.Test
 import org.junit.runner.RunWith
 
 @RunWith(AndroidJUnit4::class)
 class ReorgSmallTest : ScopedTest() {
 
+    /*
     private val targetHeight = BlockHeight.new(
         ZcashNetwork.Mainnet,
         663250
     )
     private val hashBeforeReorg = "09ec0d5de30d290bc5a2318fbf6a2427a81c7db4790ce0e341a96aeac77108b9"
     private val hashAfterReorg = "tbd"
+     */
 
     @Before
     fun setup() {
-        sithLord.await()
+        // sithLord.await()
     }
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testBeforeReorg_latestBlockHash() = timeout(30_000L) {
-        validator.validateBlockHash(targetHeight, hashBeforeReorg)
+        // validator.validateBlockHash(targetHeight, hashBeforeReorg)
     }
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testAfterReorg_callbackTriggered() = timeout(30_000L) {
         hadReorg = false
 //        sithLord.triggerSmallReorg()
-        sithLord.await()
+//         sithLord.await()
         assertTrue(hadReorg)
     }
 
     @Test
+    @Ignore("Temporarily disabled")
     fun testAfterReorg_latestBlockHash() = timeout(30_000L) {
-        validator.validateBlockHash(targetHeight, hashAfterReorg)
+        // validator.validateBlockHash(targetHeight, hashAfterReorg)
     }
 
     companion object {
diff --git a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/DarksideTestCoordinator.kt b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/DarksideTestCoordinator.kt
index 76526d06..912258f6 100644
--- a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/DarksideTestCoordinator.kt
+++ b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/DarksideTestCoordinator.kt
@@ -2,7 +2,6 @@ package cash.z.ecc.android.sdk.darkside.test
 
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.platform.app.InstrumentationRegistry
-import cash.z.ecc.android.sdk.Synchronizer
 import cash.z.ecc.android.sdk.model.Account
 import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.Darkside
@@ -13,15 +12,14 @@ import co.electriccoin.lightwallet.client.model.BlockHeightUnsafe
 import co.electriccoin.lightwallet.client.model.LightWalletEndpoint
 import io.grpc.StatusRuntimeException
 import kotlinx.coroutines.delay
-import kotlinx.coroutines.flow.filter
 import kotlinx.coroutines.flow.first
-import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.runBlocking
 import org.junit.Assert
 import org.junit.Assert.assertEquals
-import org.junit.Assert.assertNotNull
 import org.junit.Assert.assertTrue
 
+// TODO [#1224]: Refactor and re-enable disabled darkside tests
+// TODO [#1224]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1224
 class DarksideTestCoordinator(val wallet: TestWallet) {
     constructor(
         alias: String = "DarksideTestCoordinator",
@@ -95,6 +93,7 @@ class DarksideTestCoordinator(val wallet: TestWallet) {
      * Waits for, at most, the given amount of time for the synchronizer to download and scan blocks
      * and reach a 'SYNCED' status.
      */
+    /*
     fun await(timeout: Long = 60_000L, targetHeight: BlockHeight? = null) = runBlocking {
         ScopedTest.timeoutWith(this, timeout) {
             synchronizer.status.map { status ->
@@ -110,6 +109,7 @@ class DarksideTestCoordinator(val wallet: TestWallet) {
             }.filter { it == Synchronizer.Status.SYNCED }.first()
         }
     }
+     */
 
 //    /**
 //     * Send a transaction and wait until it has been fully created and successfully submitted, which
@@ -135,13 +135,6 @@ class DarksideTestCoordinator(val wallet: TestWallet) {
 
     inner class DarksideTestValidator {
 
-        fun validateHasBlock(height: BlockHeight) {
-            runBlocking {
-                assertTrue(synchronizer.findBlockHashAsHex(height) != null)
-                assertTrue(synchronizer.findBlockHash(height)?.size ?: 0 > 0)
-            }
-        }
-
         fun validateLatestHeight(height: BlockHeight) = runBlocking<Unit> {
             val info = synchronizer.processorInfo.first()
             val networkBlockHeight = info.networkBlockHeight
@@ -152,6 +145,7 @@ class DarksideTestCoordinator(val wallet: TestWallet) {
             )
         }
 
+        /*
         fun validateMinHeightSynced(minHeight: BlockHeight) = runBlocking<Unit> {
             val info = synchronizer.processorInfo.first()
             val lastSyncedHeight = info.lastSyncedHeight
@@ -177,6 +171,7 @@ class DarksideTestCoordinator(val wallet: TestWallet) {
             val hash = runBlocking { synchronizer.findBlockHashAsHex(height) }
             assertEquals(expectedHash, hash)
         }
+         */
 
         fun onReorg(callback: (errorHeight: BlockHeight, rewindHeight: BlockHeight) -> Unit) {
             synchronizer.onChainErrorHandler = callback
diff --git a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/TestWallet.kt b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/TestWallet.kt
index 8e4cc667..6f33bd53 100644
--- a/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/TestWallet.kt
+++ b/darkside-test-lib/src/androidTest/java/cash/z/ecc/android/sdk/darkside/test/TestWallet.kt
@@ -5,6 +5,7 @@ import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.bip39.toSeed
 import cash.z.ecc.android.sdk.SdkSynchronizer
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.model.Account
 import cash.z.ecc.android.sdk.model.BlockHeight
@@ -65,7 +66,9 @@ class TestWallet(
         alias,
         endpoint,
         seed,
-        startHeight
+        startHeight,
+        // Using existing wallet init mode as simplification for the test
+        walletInitMode = WalletInitMode.ExistingWallet
     ) as SdkSynchronizer
 
     val available get() = synchronizer.saplingBalances.value?.available
@@ -105,7 +108,7 @@ class TestWallet(
     }
 
     suspend fun rewindToHeight(height: BlockHeight): TestWallet {
-        synchronizer.rewindToNearestHeight(height, false)
+        synchronizer.rewindToNearestHeight(height)
         return this
     }
 
diff --git a/demo-app/build.gradle.kts b/demo-app/build.gradle.kts
index 0fe25e31..55f174cd 100644
--- a/demo-app/build.gradle.kts
+++ b/demo-app/build.gradle.kts
@@ -137,6 +137,7 @@ dependencies {
 
     implementation(libs.bundles.grpc)
     implementation(libs.kotlinx.datetime)
+    implementation(libs.kotlinx.immutable)
 }
 
 fladle {
diff --git a/demo-app/src/androidTest/java/cash/z/wallet/sdk/sample/demoapp/SampleCodeTest.kt b/demo-app/src/androidTest/java/cash/z/wallet/sdk/sample/demoapp/SampleCodeTest.kt
index 9d03e048..304023df 100644
--- a/demo-app/src/androidTest/java/cash/z/wallet/sdk/sample/demoapp/SampleCodeTest.kt
+++ b/demo-app/src/androidTest/java/cash/z/wallet/sdk/sample/demoapp/SampleCodeTest.kt
@@ -2,6 +2,7 @@ package cash.z.wallet.sdk.sample.demoapp
 
 import androidx.test.platform.app.InstrumentationRegistry
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.demoapp.util.fromResources
 import cash.z.ecc.android.sdk.ext.convertZecToZatoshi
 import cash.z.ecc.android.sdk.ext.toHex
@@ -202,7 +203,9 @@ class SampleCodeTest {
                 network,
                 lightWalletEndpoint = LightWalletEndpoint.defaultForNetwork(network),
                 seed = seed,
-                birthday = null
+                birthday = null,
+                // Using existing wallet init mode as simplification for the test
+                walletInitMode = WalletInitMode.ExistingWallet
             )
         }
 
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ComposeActivity.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ComposeActivity.kt
index 4170a2a2..8580655b 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ComposeActivity.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ComposeActivity.kt
@@ -40,7 +40,7 @@ class ComposeActivity : ComponentActivity() {
             }
             SecretState.None -> {
                 Seed(
-                    ZcashNetwork.fromResources(applicationContext),
+                    zcashNetwork = ZcashNetwork.fromResources(applicationContext),
                     onExistingWallet = { walletViewModel.persistExistingWallet(it) },
                     onNewWallet = { walletViewModel.persistNewWallet() }
                 )
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/Navigation.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/Navigation.kt
index bb9a2c4c..7f431d51 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/Navigation.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/Navigation.kt
@@ -63,7 +63,8 @@ internal fun ComposeActivity.Navigation() {
                         }
                     },
                     goTransactions = { navController.navigateJustOnce(TRANSACTIONS) },
-                    resetSdk = { walletViewModel.resetSdk() }
+                    resetSdk = { walletViewModel.resetSdk() },
+                    rewind = { walletViewModel.rewind() }
                 )
             }
         }
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/SharedViewModel.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/SharedViewModel.kt
index f989ffa2..0035c267 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/SharedViewModel.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/SharedViewModel.kt
@@ -6,6 +6,7 @@ import androidx.lifecycle.viewModelScope
 import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.bip39.toSeed
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.demoapp.util.fromResources
 import cash.z.ecc.android.sdk.ext.onFirst
 import cash.z.ecc.android.sdk.internal.Twig
@@ -82,6 +83,8 @@ class SharedViewModel(application: Application) : AndroidViewModel(application)
                     } else {
                         birthdayHeight.value
                     },
+                    // We use restore mode as this is always initialization with an older seed
+                    walletInitMode = WalletInitMode.RestoreWallet,
                     alias = OLD_UI_SYNCHRONIZER_ALIAS
                 )
 
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/WalletCoordinatorFactory.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/WalletCoordinatorFactory.kt
index 6f1728d2..8cb1c6b8 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/WalletCoordinatorFactory.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/WalletCoordinatorFactory.kt
@@ -20,7 +20,10 @@ private val lazy = LazyWithArgument<Context, WalletCoordinator> {
         emitAll(EncryptedPreferenceKeys.PERSISTABLE_WALLET.observe(encryptedPreferenceProvider))
     }
 
-    WalletCoordinator(it, persistableWalletFlow)
+    WalletCoordinator(
+        context = it,
+        persistableWallet = persistableWalletFlow
+    )
 }
 
 fun WalletCoordinator.Companion.getInstance(context: Context) = lazy.getInstance(context)
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/getbalance/GetBalanceFragment.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/getbalance/GetBalanceFragment.kt
index cc6e6129..a0f892df 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/getbalance/GetBalanceFragment.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/getbalance/GetBalanceFragment.kt
@@ -9,7 +9,6 @@ import androidx.lifecycle.repeatOnLifecycle
 import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.bip39.toSeed
 import cash.z.ecc.android.sdk.Synchronizer
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
 import cash.z.ecc.android.sdk.demoapp.BaseDemoFragment
 import cash.z.ecc.android.sdk.demoapp.databinding.FragmentGetBalanceBinding
 import cash.z.ecc.android.sdk.demoapp.ext.requireApplicationContext
@@ -89,12 +88,6 @@ class GetBalanceFragment : BaseDemoFragment<FragmentGetBalanceBinding>() {
                         .flatMapLatest { it.progress }
                         .collect { onProgress(it) }
                 }
-                launch {
-                    sharedViewModel.synchronizerFlow
-                        .filterNotNull()
-                        .flatMapLatest { it.processorInfo }
-                        .collect { onProcessorInfoUpdated(it) }
-                }
                 launch {
                     sharedViewModel.synchronizerFlow
                         .filterNotNull()
@@ -179,10 +172,6 @@ class GetBalanceFragment : BaseDemoFragment<FragmentGetBalanceBinding>() {
             binding.textStatus.text = "Syncing blocks...${percent.toPercentage()}%"
         }
     }
-
-    private fun onProcessorInfoUpdated(info: CompactBlockProcessor.ProcessorInfo) {
-        if (info.isSyncing) binding.textStatus.text = "Syncing blocks...${info.syncProgress}%"
-    }
 }
 
 @Suppress("MagicNumber")
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listtransactions/ListTransactionsFragment.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listtransactions/ListTransactionsFragment.kt
index 9f607fce..2288ac47 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listtransactions/ListTransactionsFragment.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listtransactions/ListTransactionsFragment.kt
@@ -8,7 +8,6 @@ import androidx.lifecycle.lifecycleScope
 import androidx.lifecycle.repeatOnLifecycle
 import androidx.recyclerview.widget.LinearLayoutManager
 import cash.z.ecc.android.sdk.Synchronizer
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
 import cash.z.ecc.android.sdk.demoapp.BaseDemoFragment
 import cash.z.ecc.android.sdk.demoapp.databinding.FragmentListTransactionsBinding
 import cash.z.ecc.android.sdk.internal.Twig
@@ -55,12 +54,6 @@ class ListTransactionsFragment : BaseDemoFragment<FragmentListTransactionsBindin
                         .flatMapLatest { it.progress }
                         .collect { onProgress(it) }
                 }
-                launch {
-                    sharedViewModel.synchronizerFlow
-                        .filterNotNull()
-                        .flatMapLatest { it.processorInfo }
-                        .collect { onProcessorInfoUpdated(it) }
-                }
                 launch {
                     sharedViewModel.synchronizerFlow
                         .filterNotNull()
@@ -75,10 +68,6 @@ class ListTransactionsFragment : BaseDemoFragment<FragmentListTransactionsBindin
     // Change listeners
     //
 
-    private fun onProcessorInfoUpdated(info: CompactBlockProcessor.ProcessorInfo) {
-        if (info.isSyncing) binding.textInfo.text = "Syncing blocks...${info.syncProgress}%"
-    }
-
     @Suppress("MagicNumber")
     private fun onProgress(percent: PercentDecimal) {
         if (percent.isLessThanHundredPercent()) binding.textInfo.text = "Syncing blocks...${percent.toPercentage()}%"
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listutxos/ListUtxosFragment.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listutxos/ListUtxosFragment.kt
index 2c828736..65b17962 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listutxos/ListUtxosFragment.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/listutxos/ListUtxosFragment.kt
@@ -10,7 +10,6 @@ import androidx.lifecycle.repeatOnLifecycle
 import androidx.recyclerview.widget.LinearLayoutManager
 import cash.z.ecc.android.sdk.SdkSynchronizer
 import cash.z.ecc.android.sdk.Synchronizer
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
 import cash.z.ecc.android.sdk.demoapp.BaseDemoFragment
 import cash.z.ecc.android.sdk.demoapp.databinding.FragmentListUtxosBinding
 import cash.z.ecc.android.sdk.demoapp.ext.requireApplicationContext
@@ -173,12 +172,6 @@ class ListUtxosFragment : BaseDemoFragment<FragmentListUtxosBinding>() {
                         .flatMapLatest { it.progress }
                         .collect { onProgress(it) }
                 }
-                launch {
-                    sharedViewModel.synchronizerFlow
-                        .filterNotNull()
-                        .flatMapLatest { it.processorInfo }
-                        .collect { onProcessorInfoUpdated(it) }
-                }
                 launch {
                     sharedViewModel.synchronizerFlow
                         .filterNotNull()
@@ -198,10 +191,6 @@ class ListUtxosFragment : BaseDemoFragment<FragmentListUtxosBinding>() {
         }
     }
 
-    private fun onProcessorInfoUpdated(info: CompactBlockProcessor.ProcessorInfo) {
-        if (info.isSyncing) binding.textStatus.text = "Syncing blocks...${info.syncProgress}%"
-    }
-
     @Suppress("MagicNumber")
     private fun onProgress(percent: PercentDecimal) {
         if (percent.isLessThanHundredPercent()) binding.textStatus.text = "Syncing blocks...${percent.toPercentage()}%"
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/send/SendFragment.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/send/SendFragment.kt
index 8b89145b..439f565a 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/send/SendFragment.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/demos/send/SendFragment.kt
@@ -9,7 +9,6 @@ import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.lifecycleScope
 import androidx.lifecycle.repeatOnLifecycle
 import cash.z.ecc.android.sdk.Synchronizer
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
 import cash.z.ecc.android.sdk.demoapp.BaseDemoFragment
 import cash.z.ecc.android.sdk.demoapp.DemoConstants
 import cash.z.ecc.android.sdk.demoapp.databinding.FragmentSendBinding
@@ -93,12 +92,6 @@ class SendFragment : BaseDemoFragment<FragmentSendBinding>() {
                         .flatMapLatest { it.progress }
                         .collect { onProgress(it) }
                 }
-                launch {
-                    sharedViewModel.synchronizerFlow
-                        .filterNotNull()
-                        .flatMapLatest { it.processorInfo }
-                        .collect { onProcessorInfoUpdated(it) }
-                }
                 launch {
                     sharedViewModel.synchronizerFlow
                         .filterNotNull()
@@ -133,10 +126,6 @@ class SendFragment : BaseDemoFragment<FragmentSendBinding>() {
         }
     }
 
-    private fun onProcessorInfoUpdated(info: CompactBlockProcessor.ProcessorInfo) {
-        if (info.isSyncing) binding.textStatus.text = "Syncing blocks...${info.syncProgress}%"
-    }
-
     @Suppress("MagicNumber")
     private fun onBalance(balance: WalletBalance?) {
         this.balance = balance
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/fixture/WalletSnapshotFixture.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/fixture/WalletSnapshotFixture.kt
index 6a2bf39e..01544e21 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/fixture/WalletSnapshotFixture.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/fixture/WalletSnapshotFixture.kt
@@ -1,7 +1,7 @@
 package cash.z.ecc.android.sdk.demoapp.fixture
 
 import cash.z.ecc.android.sdk.Synchronizer
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
 import cash.z.ecc.android.sdk.demoapp.ui.screen.home.viewmodel.SynchronizerError
 import cash.z.ecc.android.sdk.demoapp.ui.screen.home.viewmodel.WalletSnapshot
 import cash.z.ecc.android.sdk.model.PercentDecimal
@@ -22,7 +22,6 @@ object WalletSnapshotFixture {
     fun new(
         status: Synchronizer.Status = STATUS,
         processorInfo: CompactBlockProcessor.ProcessorInfo = CompactBlockProcessor.ProcessorInfo(
-            null,
             null,
             null,
             null
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/view/HomeView.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/view/HomeView.kt
index c6f0305a..5afad436 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/view/HomeView.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/view/HomeView.kt
@@ -43,7 +43,8 @@ private fun ComposablePreviewHome() {
             goAddressDetails = {},
             goTransactions = {},
             goTestnetFaucet = {},
-            resetSdk = {}
+            resetSdk = {},
+            rewind = {},
         )
     }
 }
@@ -59,9 +60,15 @@ fun Home(
     goTransactions: () -> Unit,
     goTestnetFaucet: () -> Unit,
     resetSdk: () -> Unit,
+    rewind: () -> Unit,
 ) {
     Scaffold(topBar = {
-        HomeTopAppBar(isTestnet, goTestnetFaucet, resetSdk)
+        HomeTopAppBar(
+            isTestnet,
+            goTestnetFaucet,
+            resetSdk,
+            rewind
+        )
     }) { paddingValues ->
         HomeMainContent(
             paddingValues = paddingValues,
@@ -79,7 +86,8 @@ fun Home(
 private fun HomeTopAppBar(
     isTestnet: Boolean,
     goTestnetFaucet: () -> Unit,
-    resetSdk: () -> Unit
+    resetSdk: () -> Unit,
+    rewind: () -> Unit
 ) {
     TopAppBar(
         title = { Text(text = stringResource(id = R.string.app_name)) },
@@ -87,7 +95,8 @@ private fun HomeTopAppBar(
             DebugMenu(
                 isTestnet,
                 goTestnetFaucet = goTestnetFaucet,
-                resetSdk = resetSdk
+                resetSdk = resetSdk,
+                rewind = rewind,
             )
         }
     )
@@ -97,7 +106,8 @@ private fun HomeTopAppBar(
 private fun DebugMenu(
     isTestnet: Boolean,
     goTestnetFaucet: () -> Unit,
-    resetSdk: () -> Unit
+    resetSdk: () -> Unit,
+    rewind: () -> Unit
 ) {
     var expanded by rememberSaveable { mutableStateOf(false) }
     IconButton(onClick = { expanded = true }) {
@@ -117,6 +127,14 @@ private fun DebugMenu(
                 }
             )
         }
+
+        DropdownMenuItem(
+            text = { Text("Quick Rewind") },
+            onClick = {
+                rewind()
+                expanded = false
+            }
+        )
         DropdownMenuItem(
             text = { Text("Reset SDK") },
             onClick = {
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletSnapshot.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletSnapshot.kt
index 78cb3a01..31d9b1c5 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletSnapshot.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletSnapshot.kt
@@ -1,7 +1,7 @@
 package cash.z.ecc.android.sdk.demoapp.ui.screen.home.viewmodel
 
 import cash.z.ecc.android.sdk.Synchronizer
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
 import cash.z.ecc.android.sdk.ext.ZcashSdk
 import cash.z.ecc.android.sdk.model.PercentDecimal
 import cash.z.ecc.android.sdk.model.WalletBalance
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletViewModel.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletViewModel.kt
index da0f9967..54376f75 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletViewModel.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/home/viewmodel/WalletViewModel.kt
@@ -7,7 +7,8 @@ import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.bip39.toSeed
 import cash.z.ecc.android.sdk.Synchronizer
 import cash.z.ecc.android.sdk.WalletCoordinator
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
+import cash.z.ecc.android.sdk.WalletInitMode
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
 import cash.z.ecc.android.sdk.demoapp.getInstance
 import cash.z.ecc.android.sdk.demoapp.preference.EncryptedPreferenceKeys
 import cash.z.ecc.android.sdk.demoapp.preference.EncryptedPreferenceSingleton
@@ -48,7 +49,6 @@ import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.withContext
 import kotlin.time.Duration.Companion.seconds
-import kotlin.time.ExperimentalTime
 
 // To make this more multiplatform compatible, we need to remove the dependency on Context
 // for loading the preferences.
@@ -101,7 +101,7 @@ class WalletViewModel(application: Application) : AndroidViewModel(application)
             null
         )
 
-    @OptIn(ExperimentalCoroutinesApi::class, ExperimentalTime::class)
+    @OptIn(ExperimentalCoroutinesApi::class)
     val walletSnapshot: StateFlow<WalletSnapshot?> = synchronizer
         .flatMapLatest {
             if (null == it) {
@@ -143,8 +143,12 @@ class WalletViewModel(application: Application) : AndroidViewModel(application)
         val application = getApplication<Application>()
 
         viewModelScope.launch {
-            val newWallet = PersistableWallet.new(application, ZcashNetwork.fromResources(application))
-            persistExistingWallet(newWallet)
+            val newWallet = PersistableWallet.new(
+                application,
+                ZcashNetwork.fromResources(application),
+                WalletInitMode.NewWallet
+            )
+            persistWallet(newWallet)
         }
     }
 
@@ -153,6 +157,13 @@ class WalletViewModel(application: Application) : AndroidViewModel(application)
      * to see the side effects.  This would be used for a user restoring a wallet from a backup.
      */
     fun persistExistingWallet(persistableWallet: PersistableWallet) {
+        persistWallet(persistableWallet)
+    }
+
+    /**
+     * Persists a wallet asynchronously.  Clients observe [secretState] to see the side effects.
+     */
+    private fun persistWallet(persistableWallet: PersistableWallet) {
         val application = getApplication<Application>()
 
         viewModelScope.launch {
@@ -234,6 +245,18 @@ class WalletViewModel(application: Application) : AndroidViewModel(application)
     fun resetSdk() {
         walletCoordinator.resetSdk()
     }
+
+    /**
+     * This rewinds to the nearest height, i.e. 14 days back from the current chain tip.
+     */
+    fun rewind() {
+        val synchronizer = synchronizer.value
+        if (null != synchronizer) {
+            viewModelScope.launch {
+                synchronizer.quickRewind()
+            }
+        }
+    }
 }
 
 /**
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/seed/view/ConfigureSeedView.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/seed/view/ConfigureSeedView.kt
index 17e0cf9a..9341579e 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/seed/view/ConfigureSeedView.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/seed/view/ConfigureSeedView.kt
@@ -15,6 +15,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.tooling.preview.Preview
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.demoapp.R
 import cash.z.ecc.android.sdk.fixture.WalletFixture
 import cash.z.ecc.android.sdk.model.PersistableWallet
@@ -76,7 +77,8 @@ private fun ConfigureSeedMainContent(
                 val newWallet = PersistableWallet(
                     zcashNetwork,
                     WalletFixture.Alice.getBirthday(zcashNetwork),
-                    SeedPhrase.new(WalletFixture.Alice.seedPhrase)
+                    SeedPhrase.new(WalletFixture.Alice.seedPhrase),
+                    WalletInitMode.RestoreWallet
                 )
                 onExistingWallet(newWallet)
             }
@@ -88,7 +90,8 @@ private fun ConfigureSeedMainContent(
                 val newWallet = PersistableWallet(
                     zcashNetwork,
                     WalletFixture.Ben.getBirthday(zcashNetwork),
-                    SeedPhrase.new(WalletFixture.Ben.seedPhrase)
+                    SeedPhrase.new(WalletFixture.Ben.seedPhrase),
+                    WalletInitMode.RestoreWallet
                 )
                 onExistingWallet(newWallet)
             }
diff --git a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/transactions/view/Transactions.kt b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/transactions/view/TransactionsView.kt
similarity index 94%
rename from demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/transactions/view/Transactions.kt
rename to demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/transactions/view/TransactionsView.kt
index 24ced1b1..a9f9522d 100644
--- a/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/transactions/view/Transactions.kt
+++ b/demo-app/src/main/java/cash/z/ecc/android/sdk/demoapp/ui/screen/transactions/view/TransactionsView.kt
@@ -31,6 +31,8 @@ import cash.z.ecc.android.sdk.demoapp.R
 import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.model.TransactionOverview
 import cash.z.ecc.android.sdk.model.WalletAddresses
+import kotlinx.collections.immutable.ImmutableList
+import kotlinx.collections.immutable.toPersistentList
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.toList
 import kotlinx.coroutines.launch
@@ -41,7 +43,7 @@ private fun ComposablePreview() {
     MaterialTheme {
         // TODO [#1090]: Demo: Add Addresses and Transactions Compose Previews
         // TODO [#1090]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1090
-        // Transactions()
+        // TransactionsView()
     }
 }
 
@@ -72,6 +74,7 @@ fun Transactions(
                 paddingValues = paddingValues,
                 synchronizer,
                 synchronizer.transactions.collectAsStateWithLifecycle(initialValue = emptyList()).value
+                    .toPersistentList()
             )
         }
     }
@@ -110,7 +113,7 @@ private fun TransactionsTopAppBar(
 private fun TransactionsMainContent(
     paddingValues: PaddingValues,
     synchronizer: Synchronizer,
-    transactions: List<TransactionOverview>
+    transactions: ImmutableList<TransactionOverview>
 ) {
     val queryScope = rememberCoroutineScope()
     Column(
@@ -127,7 +130,7 @@ private fun TransactionsMainContent(
                     val memos = synchronizer.getMemos(it)
                     queryScope.launch {
                         memos.toList().run {
-                            Twig.debug {
+                            Twig.info {
                                 "Transaction memos: count: $size, contains: ${joinToString().ifEmpty { "-" }}"
                             }
                         }
diff --git a/gradle.properties b/gradle.properties
index bed50169..27fbff09 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -26,7 +26,7 @@ ZCASH_ASCII_GPG_KEY=
 # Configures whether release is an unstable snapshot, therefore published to the snapshot repository.
 IS_SNAPSHOT=true
 
-LIBRARY_VERSION=1.21.0-beta01
+LIBRARY_VERSION=2.0.0-rc.1
 
 # Kotlin compiler warnings can be considered errors, failing the build.
 ZCASH_IS_TREAT_WARNINGS_AS_ERRORS=true
@@ -136,6 +136,7 @@ JAVAX_ANNOTATION_VERSION=1.3.2
 JUNIT_VERSION=5.9.3
 KOTLINX_COROUTINES_VERSION=1.7.3
 KOTLINX_DATETIME_VERSION=0.4.0
+KOTLINX_IMMUTABLE_COLLECTIONS_VERSION=0.3.5
 KOTLIN_VERSION=1.9.10
 MOCKITO_KOTLIN_VERSION=2.2.0
 MOCKITO_VERSION=5.4.0
diff --git a/lightwallet-client-lib/src/main/java/co/electriccoin/lightwallet/client/model/TreeStateUnsafe.kt b/lightwallet-client-lib/src/main/java/co/electriccoin/lightwallet/client/model/TreeStateUnsafe.kt
new file mode 100644
index 00000000..3f1740a1
--- /dev/null
+++ b/lightwallet-client-lib/src/main/java/co/electriccoin/lightwallet/client/model/TreeStateUnsafe.kt
@@ -0,0 +1,28 @@
+package co.electriccoin.lightwallet.client.model
+
+import cash.z.wallet.sdk.internal.rpc.Service.TreeState
+
+class TreeStateUnsafe(
+    val encoded: ByteArray
+) {
+    companion object {
+        fun new(treeState: TreeState): TreeStateUnsafe {
+            return TreeStateUnsafe(treeState.toByteArray())
+        }
+
+        fun fromParts(
+            height: Long,
+            hash: String,
+            time: Int,
+            tree: String
+        ): TreeStateUnsafe {
+            val treeState = TreeState.newBuilder()
+                .setHeight(height)
+                .setHash(hash)
+                .setTime(time)
+                .setSaplingTree(tree)
+                .build()
+            return new(treeState)
+        }
+    }
+}
diff --git a/sdk-incubator-lib/src/androidTest/kotlin/cash/z/ecc/android/sdk/fixture/PersistableWalletFixture.kt b/sdk-incubator-lib/src/androidTest/kotlin/cash/z/ecc/android/sdk/fixture/PersistableWalletFixture.kt
index cf69700e..c3351529 100644
--- a/sdk-incubator-lib/src/androidTest/kotlin/cash/z/ecc/android/sdk/fixture/PersistableWalletFixture.kt
+++ b/sdk-incubator-lib/src/androidTest/kotlin/cash/z/ecc/android/sdk/fixture/PersistableWalletFixture.kt
@@ -1,5 +1,6 @@
 package cash.z.ecc.android.sdk.fixture
 
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.PersistableWallet
 import cash.z.ecc.android.sdk.model.SeedPhrase
@@ -15,9 +16,12 @@ object PersistableWalletFixture {
 
     val SEED_PHRASE = SeedPhraseFixture.new()
 
+    val WALLET_INIT_MODE = WalletInitMode.ExistingWallet
+
     fun new(
         network: ZcashNetwork = NETWORK,
         birthday: BlockHeight = BIRTHDAY,
-        seedPhrase: SeedPhrase = SEED_PHRASE
-    ) = PersistableWallet(network, birthday, seedPhrase)
+        seedPhrase: SeedPhrase = SEED_PHRASE,
+        walletInitMode: WalletInitMode = WALLET_INIT_MODE
+    ) = PersistableWallet(network, birthday, seedPhrase, walletInitMode)
 }
diff --git a/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/WalletCoordinator.kt b/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/WalletCoordinator.kt
index 5f478b84..ecad251f 100644
--- a/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/WalletCoordinator.kt
+++ b/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/WalletCoordinator.kt
@@ -80,6 +80,7 @@ class WalletCoordinator(
                         lightWalletEndpoint = LightWalletEndpoint.defaultForNetwork(persistableWallet.network),
                         birthday = persistableWallet.birthday,
                         seed = persistableWallet.seedPhrase.toByteArray(),
+                        walletInitMode = persistableWallet.walletInitMode,
                     )
 
                     trySend(InternalSynchronizerStatus.Available(closeableSynchronizer))
@@ -127,7 +128,7 @@ class WalletCoordinator(
         synchronizerMutex.withLock {
             synchronizer.value?.let {
                 it.latestBirthdayHeight?.let { height ->
-                    it.rewindToNearestHeight(height, true)
+                    it.rewindToNearestHeight(height)
                     return true
                 }
             }
diff --git a/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/model/PersistableWallet.kt b/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/model/PersistableWallet.kt
index 9840e9ed..41c96835 100644
--- a/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/model/PersistableWallet.kt
+++ b/sdk-incubator-lib/src/main/java/cash/z/ecc/android/sdk/model/PersistableWallet.kt
@@ -3,6 +3,7 @@ package cash.z.ecc.android.sdk.model
 import android.app.Application
 import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.bip39.toEntropy
+import cash.z.ecc.android.sdk.WalletInitMode
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import org.json.JSONObject
@@ -13,8 +14,12 @@ import org.json.JSONObject
 data class PersistableWallet(
     val network: ZcashNetwork,
     val birthday: BlockHeight?,
-    val seedPhrase: SeedPhrase
+    val seedPhrase: SeedPhrase,
+    val walletInitMode: WalletInitMode
 ) {
+    init {
+        _walletInitMode = walletInitMode
+    }
 
     /**
      * @return Wallet serialized to JSON format, suitable for long-term encrypted storage.
@@ -41,6 +46,10 @@ data class PersistableWallet(
         internal const val KEY_BIRTHDAY = "birthday"
         internal const val KEY_SEED_PHRASE = "seed_phrase"
 
+        // Note: This is not the ideal way to hold such a value. But we also want to avoid persisting the wallet
+        // initialization mode with the persistable wallet.
+        private var _walletInitMode: WalletInitMode = WalletInitMode.ExistingWallet
+
         fun from(jsonObject: JSONObject): PersistableWallet {
             when (val version = jsonObject.getInt(KEY_VERSION)) {
                 VERSION_1 -> {
@@ -56,7 +65,12 @@ data class PersistableWallet(
                     }
                     val seedPhrase = jsonObject.getString(KEY_SEED_PHRASE)
 
-                    return PersistableWallet(network, birthday, SeedPhrase.new(seedPhrase))
+                    return PersistableWallet(
+                        network = network,
+                        birthday = birthday,
+                        seedPhrase = SeedPhrase.new(seedPhrase),
+                        walletInitMode = _walletInitMode
+                    )
                 }
                 else -> {
                     throw IllegalArgumentException("Unsupported version $version")
@@ -67,12 +81,21 @@ data class PersistableWallet(
         /**
          * @return A new PersistableWallet with a random seed phrase.
          */
-        suspend fun new(application: Application, zcashNetwork: ZcashNetwork): PersistableWallet {
+        suspend fun new(
+            application: Application,
+            zcashNetwork: ZcashNetwork,
+            walletInitMode: WalletInitMode
+        ): PersistableWallet {
             val birthday = BlockHeight.ofLatestCheckpoint(application, zcashNetwork)
 
             val seedPhrase = newSeedPhrase()
 
-            return PersistableWallet(zcashNetwork, birthday, seedPhrase)
+            return PersistableWallet(
+                zcashNetwork,
+                birthday,
+                seedPhrase,
+                walletInitMode
+            )
         }
     }
 }
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessorTest.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessorTest.kt
new file mode 100644
index 00000000..54df3b6e
--- /dev/null
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessorTest.kt
@@ -0,0 +1,8 @@
+package cash.z.ecc.android.sdk.block.processor
+
+// TODO [#1094]: Consider fake SDK sync related components
+// TODO [#1094]: Testing the CompactBlockProcessor is only available once we can mock the necessary core components like
+//  [CompactBlockDownloader], [DerivedDataRepository], or [TypesafeBackend]
+// TODO [#1094]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1094
+@Suppress("EmptyClassBlock")
+class CompactBlockProcessorTest
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/integration/TestnetIntegrationTest.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/integration/TestnetIntegrationTest.kt
index 02224d19..05aadfb1 100644
--- a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/integration/TestnetIntegrationTest.kt
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/integration/TestnetIntegrationTest.kt
@@ -4,6 +4,7 @@ import androidx.test.filters.LargeTest
 import androidx.test.platform.app.InstrumentationRegistry
 import cash.z.ecc.android.sdk.Synchronizer
 import cash.z.ecc.android.sdk.Synchronizer.Status.SYNCED
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.ext.ZcashSdk
 import cash.z.ecc.android.sdk.ext.onFirst
 import cash.z.ecc.android.sdk.internal.Twig
@@ -141,7 +142,9 @@ class TestnetIntegrationTest : ScopedTest() {
                 lightWalletEndpoint =
                 lightWalletEndpoint,
                 seed = seed,
-                birthday = BlockHeight.new(ZcashNetwork.Testnet, birthdayHeight)
+                birthday = BlockHeight.new(ZcashNetwork.Testnet, birthdayHeight),
+                // Using existing wallet init mode as simplification for the test
+                walletInitMode = WalletInitMode.ExistingWallet
             )
         }
     }
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/SdkSynchronizerTest.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/SdkSynchronizerTest.kt
index 7ace2e5e..d41fcb67 100644
--- a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/SdkSynchronizerTest.kt
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/internal/SdkSynchronizerTest.kt
@@ -4,6 +4,7 @@ import androidx.test.filters.SmallTest
 import androidx.test.platform.app.InstrumentationRegistry
 import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.fixture.WalletFixture
 import cash.z.ecc.android.sdk.model.ZcashNetwork
 import cash.z.ecc.android.sdk.model.defaultForNetwork
@@ -29,7 +30,9 @@ class SdkSynchronizerTest {
             alias,
             LightWalletEndpoint.defaultForNetwork(ZcashNetwork.Mainnet),
             Mnemonics.MnemonicCode(WalletFixture.SEED_PHRASE).toEntropy(),
-            birthday = null
+            birthday = null,
+            // Using existing wallet init mode as simplification for the test
+            walletInitMode = WalletInitMode.ExistingWallet
         ).use {
             assertFailsWith<IllegalStateException> {
                 Synchronizer.new(
@@ -38,7 +41,9 @@ class SdkSynchronizerTest {
                     alias,
                     LightWalletEndpoint.defaultForNetwork(ZcashNetwork.Mainnet),
                     Mnemonics.MnemonicCode(WalletFixture.SEED_PHRASE).toEntropy(),
-                    birthday = null
+                    birthday = null,
+                    // Using existing wallet init mode as simplification for the test
+                    walletInitMode = WalletInitMode.ExistingWallet
                 )
             }
         }
@@ -51,6 +56,8 @@ class SdkSynchronizerTest {
         // Random alias so that repeated invocations of this test will have a clean starting state
         val alias = UUID.randomUUID().toString()
 
+        // TODO [#1094]: Consider fake SDK sync related components
+        // TODO [#1094]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1094
         // In the future, inject fake networking component so that it doesn't require hitting the network
         Synchronizer.new(
             InstrumentationRegistry.getInstrumentation().context,
@@ -58,7 +65,9 @@ class SdkSynchronizerTest {
             alias,
             LightWalletEndpoint.defaultForNetwork(ZcashNetwork.Mainnet),
             Mnemonics.MnemonicCode(WalletFixture.SEED_PHRASE).toEntropy(),
-            birthday = null
+            birthday = null,
+            // Using existing wallet init mode as simplification for the test
+            walletInitMode = WalletInitMode.ExistingWallet
         ).use {}
 
         // Second instance should succeed because first one was closed
@@ -68,7 +77,9 @@ class SdkSynchronizerTest {
             alias,
             LightWalletEndpoint.defaultForNetwork(ZcashNetwork.Mainnet),
             Mnemonics.MnemonicCode(WalletFixture.SEED_PHRASE).toEntropy(),
-            birthday = null
+            birthday = null,
+            // Using existing wallet init mode as simplification for the test
+            walletInitMode = WalletInitMode.ExistingWallet
         ).use {}
     }
 }
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/BalancePrinterUtil.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/BalancePrinterUtil.kt
index 53a7a611..59805a03 100644
--- a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/BalancePrinterUtil.kt
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/BalancePrinterUtil.kt
@@ -3,6 +3,7 @@ package cash.z.ecc.android.sdk.util
 import androidx.test.platform.app.InstrumentationRegistry
 import cash.z.ecc.android.sdk.CloseableSynchronizer
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.internal.ext.deleteSuspend
 import cash.z.ecc.android.sdk.internal.model.Checkpoint
@@ -59,9 +60,6 @@ class BalancePrinterUtil {
 //        val lastDownloaded = downloader.getLastDownloadedHeight()
 //        val blockRange = (Math.max(birthday, lastDownloaded))..latestBlockHeight
 //        downloadNewBlocks(blockRange)
-//        val error = validateNewBlocks(blockRange)
-//        twig("validation completed with result $error")
-//        assertEquals(-1, error)
     }
 
     private suspend fun deleteDb(dbName: String) {
@@ -99,7 +97,9 @@ class BalancePrinterUtil {
                     lightWalletEndpoint = LightWalletEndpoint
                         .defaultForNetwork(network),
                     seed = seed,
-                    birthday = birthdayHeight
+                    birthday = birthdayHeight,
+                    // Using existing wallet init mode as simplification for the test
+                    walletInitMode = WalletInitMode.ExistingWallet
                 )
 
 //            deleteDb(dataDbPath)
@@ -150,13 +150,4 @@ class BalancePrinterUtil {
 //            }
 //        }
 //    }
-
-//    private fun validateNewBlocks(range: IntRange?): Int {
-// //        val dummyWallet = initWallet("dummySeed")
-//        Twig.sprout("validating")
-//        twig("validating blocks in range $range")
-// //        val result = rustBackend.validateCombinedChain()
-//        Twig.clip("validating")
-//        return result
-//    }
 }
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/DataDbScannerUtil.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/DataDbScannerUtil.kt
index ec510f49..f570a852 100644
--- a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/DataDbScannerUtil.kt
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/DataDbScannerUtil.kt
@@ -4,6 +4,7 @@ import androidx.test.platform.app.InstrumentationRegistry
 import cash.z.ecc.android.sdk.CloseableSynchronizer
 import cash.z.ecc.android.sdk.SdkSynchronizer
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.ZcashNetwork
 import cash.z.ecc.android.sdk.model.defaultForNetwork
@@ -72,7 +73,9 @@ class DataDbScannerUtil {
             birthday = BlockHeight.new(
                 ZcashNetwork.Mainnet,
                 birthdayHeight
-            )
+            ),
+            // Using existing wallet init mode as simplification for the test
+            walletInitMode = WalletInitMode.ExistingWallet
         )
 
         println("sync!")
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/TestWallet.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/TestWallet.kt
index 992dbae8..919388da 100644
--- a/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/TestWallet.kt
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/android/sdk/util/TestWallet.kt
@@ -5,6 +5,7 @@ import cash.z.ecc.android.bip39.Mnemonics
 import cash.z.ecc.android.bip39.toSeed
 import cash.z.ecc.android.sdk.SdkSynchronizer
 import cash.z.ecc.android.sdk.Synchronizer
+import cash.z.ecc.android.sdk.WalletInitMode
 import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.internal.deriveUnifiedSpendingKey
 import cash.z.ecc.android.sdk.internal.jni.RustDerivationTool
@@ -66,7 +67,9 @@ class TestWallet(
         alias,
         lightWalletEndpoint = endpoint,
         seed = seed,
-        startHeight
+        startHeight,
+        // Using existing wallet init mode as simplification for the test
+        walletInitMode = WalletInitMode.ExistingWallet
     ) as SdkSynchronizer
 
     val available get() = synchronizer.saplingBalances.value?.available
@@ -106,7 +109,7 @@ class TestWallet(
     }
 
     suspend fun rewindToHeight(height: BlockHeight): TestWallet {
-        synchronizer.rewindToNearestHeight(height, false)
+        synchronizer.rewindToNearestHeight(height)
         return this
     }
 
diff --git a/sdk-lib/src/androidTest/java/cash/z/ecc/fixture/FakeRustBackend.kt b/sdk-lib/src/androidTest/java/cash/z/ecc/fixture/FakeRustBackend.kt
index 685643dc..0a7762c8 100644
--- a/sdk-lib/src/androidTest/java/cash/z/ecc/fixture/FakeRustBackend.kt
+++ b/sdk-lib/src/androidTest/java/cash/z/ecc/fixture/FakeRustBackend.kt
@@ -2,6 +2,9 @@ package cash.z.ecc.fixture
 
 import cash.z.ecc.android.sdk.internal.Backend
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.internal.model.JniScanProgress
+import cash.z.ecc.android.sdk.internal.model.JniScanRange
+import cash.z.ecc.android.sdk.internal.model.JniSubtreeRoot
 import cash.z.ecc.android.sdk.internal.model.JniUnifiedSpendingKey
 
 internal class FakeRustBackend(
@@ -17,11 +20,35 @@ internal class FakeRustBackend(
         metadata.removeAll { it.height > height }
     }
 
-    override suspend fun getLatestHeight(): Long = metadata.maxOf { it.height }
-    override suspend fun validateCombinedChainOrErrorHeight(limit: Long?): Long? {
+    override suspend fun putSaplingSubtreeRoots(
+        startIndex: Long,
+        roots: List<JniSubtreeRoot>,
+    ) {
         TODO("Not yet implemented")
     }
 
+    override suspend fun updateChainTip(height: Long) {
+        TODO("Not yet implemented")
+    }
+
+    override suspend fun getFullyScannedHeight(): Long? {
+        TODO("Not yet implemented")
+    }
+
+    override suspend fun getMaxScannedHeight(): Long? {
+        TODO("Not yet implemented")
+    }
+
+    override suspend fun getScanProgress(): JniScanProgress {
+        TODO("Not yet implemented")
+    }
+
+    override suspend fun suggestScanRanges(): List<JniScanRange> {
+        TODO("Not yet implemented")
+    }
+
+    override suspend fun getLatestCacheHeight(): Long = metadata.maxOf { it.height }
+
     override suspend fun getVerifiedTransparentBalance(address: String): Long {
         TODO("Not yet implemented")
     }
@@ -58,34 +85,25 @@ internal class FakeRustBackend(
         to: String,
         value: Long,
         memo: ByteArray?
-    ): Long {
+    ): ByteArray {
         TODO("Not yet implemented")
     }
 
-    override suspend fun shieldToAddress(account: Int, unifiedSpendingKey: ByteArray, memo: ByteArray?): Long {
+    override suspend fun shieldToAddress(account: Int, unifiedSpendingKey: ByteArray, memo: ByteArray?): ByteArray {
         TODO("Not yet implemented")
     }
 
     override suspend fun decryptAndStoreTransaction(tx: ByteArray) =
         error("Intentionally not implemented in mocked FakeRustBackend implementation.")
 
-    override suspend fun initAccountsTable(vararg keys: String) {
-        TODO("Not yet implemented")
-    }
-
-    override suspend fun initBlocksTable(
-        checkpointHeight: Long,
-        checkpointHash: String,
-        checkpointTime: Long,
-        checkpointSaplingTree: String
-    ) {
-        TODO("Not yet implemented")
-    }
-
     override suspend fun initDataDb(seed: ByteArray?): Int =
         error("Intentionally not implemented in mocked FakeRustBackend implementation.")
 
-    override suspend fun createAccount(seed: ByteArray): JniUnifiedSpendingKey =
+    override suspend fun createAccount(
+        seed: ByteArray,
+        treeState: ByteArray,
+        recoverUntil: Long?
+    ): JniUnifiedSpendingKey =
         error("Intentionally not implemented in mocked FakeRustBackend implementation.")
 
     override fun isValidShieldedAddr(addr: String): Boolean =
@@ -119,10 +137,7 @@ internal class FakeRustBackend(
         TODO("Not yet implemented")
     }
 
-    override suspend fun getReceivedMemoAsUtf8(idNote: Long): String? =
-        error("Intentionally not implemented in mocked FakeRustBackend implementation.")
-
-    override suspend fun getSentMemoAsUtf8(idNote: Long): String? =
+    override suspend fun getMemoAsUtf8(txId: ByteArray, outputIndex: Int): String? =
         error("Intentionally not implemented in mocked FakeRustBackend implementation.")
 
     override suspend fun getVerifiedBalance(account: Int): Long {
@@ -133,6 +148,6 @@ internal class FakeRustBackend(
         TODO("Not yet implemented")
     }
 
-    override suspend fun scanBlocks(limit: Long?) =
+    override suspend fun scanBlocks(fromHeight: Long, limit: Long) =
         error("Intentionally not implemented in mocked FakeRustBackend implementation.")
 }
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/SdkSynchronizer.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/SdkSynchronizer.kt
index 6ecccb71..7fedfcd4 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/SdkSynchronizer.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/SdkSynchronizer.kt
@@ -5,12 +5,12 @@ import cash.z.ecc.android.sdk.Synchronizer.Status.DISCONNECTED
 import cash.z.ecc.android.sdk.Synchronizer.Status.STOPPED
 import cash.z.ecc.android.sdk.Synchronizer.Status.SYNCED
 import cash.z.ecc.android.sdk.Synchronizer.Status.SYNCING
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor.State.Disconnected
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor.State.Initialized
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor.State.Stopped
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor.State.Synced
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor.State.Syncing
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor.State.Disconnected
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor.State.Initialized
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor.State.Stopped
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor.State.Synced
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor.State.Syncing
 import cash.z.ecc.android.sdk.exception.TransactionEncoderException
 import cash.z.ecc.android.sdk.exception.TransactionSubmitException
 import cash.z.ecc.android.sdk.ext.ConsensusBranchId
@@ -24,10 +24,11 @@ import cash.z.ecc.android.sdk.internal.db.DatabaseCoordinator
 import cash.z.ecc.android.sdk.internal.db.derived.DbDerivedDataRepository
 import cash.z.ecc.android.sdk.internal.db.derived.DerivedDataDb
 import cash.z.ecc.android.sdk.internal.ext.isNullOrEmpty
-import cash.z.ecc.android.sdk.internal.ext.toHexReversed
 import cash.z.ecc.android.sdk.internal.ext.tryNull
 import cash.z.ecc.android.sdk.internal.jni.RustBackend
 import cash.z.ecc.android.sdk.internal.model.Checkpoint
+import cash.z.ecc.android.sdk.internal.model.TreeState
+import cash.z.ecc.android.sdk.internal.model.ext.toBlockHeight
 import cash.z.ecc.android.sdk.internal.repository.CompactBlockRepository
 import cash.z.ecc.android.sdk.internal.repository.DerivedDataRepository
 import cash.z.ecc.android.sdk.internal.storage.block.FileCompactBlockRepository
@@ -40,7 +41,6 @@ import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.PercentDecimal
 import cash.z.ecc.android.sdk.model.TransactionOverview
 import cash.z.ecc.android.sdk.model.TransactionRecipient
-import cash.z.ecc.android.sdk.model.UnifiedFullViewingKey
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.WalletBalance
 import cash.z.ecc.android.sdk.model.Zatoshi
@@ -52,6 +52,7 @@ import cash.z.ecc.android.sdk.type.AddressType.Unified
 import cash.z.ecc.android.sdk.type.ConsensusMatchType
 import co.electriccoin.lightwallet.client.LightWalletClient
 import co.electriccoin.lightwallet.client.model.LightWalletEndpoint
+import co.electriccoin.lightwallet.client.model.Response
 import co.electriccoin.lightwallet.client.new
 import kotlinx.coroutines.CoroutineExceptionHandler
 import kotlinx.coroutines.CoroutineScope
@@ -109,6 +110,10 @@ class SdkSynchronizer private constructor(
         private val mutex = Mutex()
 
         /**
+         * Convenience method to create new SdkSynchronizer instance.
+         *
+         * @return Synchronizer instance as CloseableSynchronizer
+         *
          * @throws IllegalStateException If multiple instances of synchronizer with the same network+alias are
          * active at the same time.  Call `close` to finish one synchronizer before starting another one with the same
          * network+alias.
@@ -172,21 +177,17 @@ class SdkSynchronizer private constructor(
         }
     }
 
-    // pools
-    private val _orchardBalances = MutableStateFlow<WalletBalance?>(null)
-    private val _saplingBalances = MutableStateFlow<WalletBalance?>(null)
-    private val _transparentBalances = MutableStateFlow<WalletBalance?>(null)
-
     private val _status = MutableStateFlow<Synchronizer.Status>(DISCONNECTED)
 
     var coroutineScope: CoroutineScope = CoroutineScope(SupervisorJob() + Dispatchers.Main)
 
-    override val orchardBalances = _orchardBalances.asStateFlow()
-    override val saplingBalances = _saplingBalances.asStateFlow()
-    override val transparentBalances = _transparentBalances.asStateFlow()
+    override val orchardBalances = processor.orchardBalances.asStateFlow()
+    override val saplingBalances = processor.saplingBalances.asStateFlow()
+    override val transparentBalances = processor.transparentBalances.asStateFlow()
+
     override val transactions
         get() = combine(processor.networkHeight, storage.allTransactions) { networkHeight, allTransactions ->
-            val latestBlockHeight = networkHeight ?: storage.lastScannedHeight()
+            val latestBlockHeight = networkHeight ?: backend.getMaxScannedHeight()
             allTransactions.map { TransactionOverview.new(it, latestBlockHeight) }
         }
 
@@ -305,8 +306,8 @@ class SdkSynchronizer private constructor(
     override suspend fun getNearestRewindHeight(height: BlockHeight): BlockHeight =
         processor.getNearestRewindHeight(height)
 
-    override suspend fun rewindToNearestHeight(height: BlockHeight, alsoClearBlockCache: Boolean) {
-        processor.rewindToNearestHeight(height, alsoClearBlockCache)
+    override suspend fun rewindToNearestHeight(height: BlockHeight) {
+        processor.rewindToNearestHeight(height)
     }
 
     override suspend fun quickRewind() {
@@ -314,18 +315,10 @@ class SdkSynchronizer private constructor(
     }
 
     override fun getMemos(transactionOverview: TransactionOverview): Flow<String> {
-        return storage.getNoteIds(transactionOverview.id).map {
+        return storage.getSaplingOutputIndices(transactionOverview.id).map {
             runCatching {
-                when (transactionOverview.isSentTransaction) {
-                    true -> {
-                        backend.getSentMemoAsUtf8(it)
-                    }
-                    false -> {
-                        backend.getReceivedMemoAsUtf8(it)
-                    }
-                }
+                backend.getMemoAsUtf8(transactionOverview.rawId.byteArray, it)
             }.onFailure {
-                // https://github.com/zcash/librustzcash/issues/834
                 Twig.error { "Failed to get memo with: $it" }
             }.onSuccess {
                 Twig.debug { "Transaction memo queried: $it" }
@@ -350,14 +343,6 @@ class SdkSynchronizer private constructor(
     //  to do with the underlying data
     // TODO [#682]: https://github.com/zcash/zcash-android-wallet-sdk/issues/682
 
-    suspend fun findBlockHash(height: BlockHeight): ByteArray? {
-        return storage.findBlockHash(height)
-    }
-
-    suspend fun findBlockHashAsHex(height: BlockHeight): String? {
-        return findBlockHash(height)?.toHexReversed()
-    }
-
     suspend fun getTransactionCount(): Int {
         return storage.getTransactionCount().toInt()
     }
@@ -366,44 +351,49 @@ class SdkSynchronizer private constructor(
         storage.invalidate()
     }
 
-    //
-    // Private API
-    //
-
     /**
-     * Calculate the latest balance, based on the blocks that have been scanned and transmit this
-     * information into the flow of [balances].
+     * Calculate the latest balance based on the blocks that have been scanned and transmit this information into the
+     * [transparentBalances] and [saplingBalances] flow. The [orchardBalances] flow is still not filled with proper data
+     * because of the current limited Orchard support.
      */
     suspend fun refreshAllBalances() {
-        refreshSaplingBalance()
-        refreshTransparentBalance()
+        processor.checkAllBalances()
         // TODO [#682]: refresh orchard balance
         // TODO [#682]: https://github.com/zcash/zcash-android-wallet-sdk/issues/682
         Twig.warn { "Warning: Orchard balance does not yet refresh. Only some of the plumbing is in place." }
     }
 
+    /**
+     * Calculate the latest Sapling balance based on the blocks that have been scanned and transmit this information
+     * into the [saplingBalances] flow.
+     */
     suspend fun refreshSaplingBalance() {
-        Twig.debug { "refreshing sapling balance" }
-        _saplingBalances.value = processor.getBalanceInfo(Account.DEFAULT)
+        processor.checkSaplingBalance()
     }
 
+    /**
+     * Calculate the latest Transparent balance based on the blocks that have been scanned and transmit this information
+     * into the [saplingBalances] flow.
+     */
     suspend fun refreshTransparentBalance() {
-        Twig.debug { "refreshing transparent balance" }
-        _transparentBalances.value = processor.getUtxoCacheBalance(getTransparentAddress(Account.DEFAULT))
+        processor.checkTransparentBalance()
     }
 
     suspend fun isValidAddress(address: String): Boolean {
         return !validateAddress(address).isNotValid
     }
 
+    //
+    // Private API
+    //
+
     private fun CoroutineScope.onReady() {
         Twig.debug { "Starting synchronizer…" }
 
-        // Triggering UTXOs fetch and transparent balance update at the beginning of the block sync right after the app
-        // start, as it makes the transparent transactions appearance faster
+        // Triggering UTXOs and transactions fetching at the beginning of the block synchronization right after the
+        //  app starts makes the transparent transactions appear faster.
         launch(CoroutineExceptionHandler(::onCriticalError)) {
             refreshUtxos(Account.DEFAULT)
-            refreshTransparentBalance()
             refreshTransactions()
         }
 
@@ -520,8 +510,21 @@ class SdkSynchronizer private constructor(
     //
 
     // Not ready to be a public API; internal for testing only
-    internal suspend fun createAccount(seed: ByteArray): UnifiedSpendingKey =
-        backend.createAccountAndGetSpendingKey(seed)
+    internal suspend fun createAccount(
+        seed: ByteArray,
+        treeState: TreeState,
+        recoverUntil: BlockHeight?
+    ): UnifiedSpendingKey? {
+        return runCatching {
+            backend.createAccountAndGetSpendingKey(
+                seed = seed,
+                treeState = treeState,
+                recoverUntil = recoverUntil
+            )
+        }.onFailure {
+            Twig.error(it) { "Create account failed." }
+        }.getOrNull()
+    }
 
     /**
      * Returns the current Unified Address for this account.
@@ -623,9 +626,30 @@ class SdkSynchronizer private constructor(
 
     override suspend fun validateConsensusBranch(): ConsensusMatchType {
         val serverBranchId = tryNull { processor.downloader.getServerInfo()?.consensusBranchId }
-        val sdkBranchId = tryNull {
-            (txManager as OutboundTransactionManagerImpl).encoder.getConsensusBranchId()
+
+        val currentChainTip = when (
+            val response =
+                processor.downloader.getLatestBlockHeight()
+        ) {
+            is Response.Success -> {
+                Twig.info { "Chain tip for validate consensus branch action fetched: ${response.result.value}" }
+                runCatching { response.result.toBlockHeight(network) }.getOrNull()
+            }
+            is Response.Failure -> {
+                Twig.error {
+                    "Chain tip fetch failed for validate consensus branch action with:" +
+                        " ${response.toThrowable()}"
+                }
+                null
+            }
         }
+
+        val sdkBranchId = currentChainTip?.let {
+            tryNull {
+                (txManager as OutboundTransactionManagerImpl).encoder.getConsensusBranchId(currentChainTip)
+            }
+        }
+
         return ConsensusMatchType(
             sdkBranchId?.let { ConsensusBranchId.fromId(it) },
             serverBranchId?.let { ConsensusBranchId.fromHex(it) }
@@ -665,7 +689,8 @@ internal object DefaultSynchronizerFactory {
         zcashNetwork: ZcashNetwork,
         checkpoint: Checkpoint,
         seed: ByteArray?,
-        viewingKeys: List<UnifiedFullViewingKey>
+        numberOfAccounts: Int,
+        recoverUntil: BlockHeight?
     ): DerivedDataRepository =
         DbDerivedDataRepository(
             DerivedDataDb.new(
@@ -675,7 +700,8 @@ internal object DefaultSynchronizerFactory {
                 zcashNetwork,
                 checkpoint,
                 seed,
-                viewingKeys
+                numberOfAccounts,
+                recoverUntil
             )
         )
 
@@ -718,10 +744,10 @@ internal object DefaultSynchronizerFactory {
         repository: DerivedDataRepository,
         birthdayHeight: BlockHeight
     ): CompactBlockProcessor = CompactBlockProcessor(
-        downloader,
-        repository,
-        backend,
-        birthdayHeight
+        downloader = downloader,
+        repository = repository,
+        backend = backend,
+        minimumHeight = birthdayHeight
     )
 }
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/Synchronizer.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/Synchronizer.kt
index 33507f97..ee37fdf6 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/Synchronizer.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/Synchronizer.kt
@@ -1,11 +1,13 @@
 package cash.z.ecc.android.sdk
 
 import android.content.Context
-import cash.z.ecc.android.sdk.block.CompactBlockProcessor
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
 import cash.z.ecc.android.sdk.ext.ZcashSdk
 import cash.z.ecc.android.sdk.internal.Derivation
 import cash.z.ecc.android.sdk.internal.SaplingParamTool
+import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.internal.db.DatabaseCoordinator
+import cash.z.ecc.android.sdk.internal.model.ext.toBlockHeight
 import cash.z.ecc.android.sdk.model.Account
 import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.PercentDecimal
@@ -16,10 +18,10 @@ import cash.z.ecc.android.sdk.model.WalletBalance
 import cash.z.ecc.android.sdk.model.Zatoshi
 import cash.z.ecc.android.sdk.model.ZcashNetwork
 import cash.z.ecc.android.sdk.tool.CheckpointTool
-import cash.z.ecc.android.sdk.tool.DerivationTool
 import cash.z.ecc.android.sdk.type.AddressType
 import cash.z.ecc.android.sdk.type.ConsensusMatchType
 import co.electriccoin.lightwallet.client.model.LightWalletEndpoint
+import co.electriccoin.lightwallet.client.model.Response
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.runBlocking
@@ -163,7 +165,7 @@ interface Synchronizer {
      * Sends zatoshi.
      *
      * @param usk the unified spending key associated with the notes that will be spent.
-     * @param zatoshi the amount of zatoshi to send.
+     * @param amount the amount of zatoshi to send.
      * @param toAddress the recipient's address.
      * @param memo the optional memo to include as part of the transaction.
      *
@@ -268,16 +270,27 @@ interface Synchronizer {
      */
     suspend fun getTransparentBalance(tAddr: String): WalletBalance
 
-    suspend fun getNearestRewindHeight(height: BlockHeight): BlockHeight
-
     /**
      * Returns the safest height to which we can rewind, given a desire to rewind to the height
      * provided. Due to how witness incrementing works, a wallet cannot simply rewind to any
      * arbitrary height. This handles all that complexity yet remains flexible in the future as
      * improvements are made.
      */
-    suspend fun rewindToNearestHeight(height: BlockHeight, alsoClearBlockCache: Boolean = false)
+    suspend fun getNearestRewindHeight(height: BlockHeight): BlockHeight
 
+    /**
+     * Rewinds to the safest height to which we can rewind, given a desire to rewind to the height
+     * provided. Due to how witness incrementing works, a wallet cannot simply rewind to any
+     * arbitrary height. This handles all that complexity yet remains flexible in the future as
+     * improvements are made.
+     */
+    suspend fun rewindToNearestHeight(height: BlockHeight)
+
+    /**
+     * Rewinds to the safest height approximately 14 days backward from the current chain tip. Due to how witness
+     * incrementing works, a wallet cannot simply rewind to any arbitrary height. This handles all that complexity
+     * yet remains flexible in the future as improvements are made.
+     */
     suspend fun quickRewind()
 
     /**
@@ -398,20 +411,32 @@ interface Synchronizer {
          * Primary method that SDK clients will use to construct a synchronizer.
          *
          * @param zcashNetwork the network to use.
+         *
          * @param alias A string used to segregate multiple wallets in the filesystem.  This implies the string
          * should not contain characters unsuitable for the platform's filesystem.  The default value is
          * generally used unless an SDK client needs to support multiple wallets.
+         *
          * @param lightWalletEndpoint Server endpoint.  See [cash.z.ecc.android.sdk.model.defaultForNetwork]. If a
          * client wishes to change the server endpoint, the active synchronizer will need to be stopped and a new
          * instance created with a new value.
+         *
          * @param seed the wallet's seed phrase. This is required the first time a new wallet is set up. For
          * subsequent calls, seed is only needed if [InitializerException.SeedRequired] is thrown.
+         *
          * @param birthday Block height representing the "birthday" of the wallet.  When creating a new wallet, see
          * [BlockHeight.ofLatestCheckpoint].  When restoring an existing wallet, use block height that was first used
          * to create the wallet.  If that value is unknown, null is acceptable but will result in longer
          * sync times.  After sync completes, the birthday can be determined from [Synchronizer.latestBirthdayHeight].
+         *
+         * @param walletInitMode a required parameter with one of [WalletInitMode] values. Use
+         * [WalletInitMode.NewWallet] when starting synchronizer for a newly created wallet. Or use
+         * [WalletInitMode.RestoreWallet] when restoring an existing wallet that was created at some point in the
+         * past. Or use the last [WalletInitMode.ExistingWallet] type for a wallet which is already initialized
+         * and needs follow-up block synchronization.
+         *
          * @throws InitializerException.SeedRequired Indicates clients need to call this method again, providing the
          * seed bytes.
+         *
          * @throws IllegalStateException If multiple instances of synchronizer with the same network+alias are
          * active at the same time.  Call `close` to finish one synchronizer before starting another one with the same
          * network+alias.
@@ -427,7 +452,8 @@ interface Synchronizer {
             alias: String = ZcashSdk.DEFAULT_ALIAS,
             lightWalletEndpoint: LightWalletEndpoint,
             seed: ByteArray?,
-            birthday: BlockHeight?
+            birthday: BlockHeight?,
+            walletInitMode: WalletInitMode
         ): CloseableSynchronizer {
             val applicationContext = context.applicationContext
 
@@ -456,46 +482,57 @@ interface Synchronizer {
                 DefaultSynchronizerFactory
                     .defaultCompactBlockRepository(coordinator.fsBlockDbRoot(zcashNetwork, alias), backend)
 
-            val viewingKeys = seed?.let {
-                DerivationTool.getInstance().deriveUnifiedFullViewingKeys(
-                    seed,
-                    zcashNetwork,
-                    Derivation.DEFAULT_NUMBER_OF_ACCOUNTS
-                ).toList()
-            } ?: emptyList()
+            val service = DefaultSynchronizerFactory.defaultService(applicationContext, lightWalletEndpoint)
+            val downloader = DefaultSynchronizerFactory.defaultDownloader(service, blockStore)
+
+            val chainTip = when (walletInitMode) {
+                is WalletInitMode.RestoreWallet -> {
+                    when (val response = downloader.getLatestBlockHeight()) {
+                        is Response.Success -> {
+                            Twig.info { "Chain tip for recovery until param fetched: ${response.result.value}" }
+                            runCatching { response.result.toBlockHeight(zcashNetwork) }.getOrNull()
+                        }
+                        is Response.Failure -> {
+                            Twig.error { "Chain tip fetch for recovery until failed with: ${response.toThrowable()}" }
+                            null
+                        }
+                    }
+                }
+                else -> {
+                    null
+                }
+            }
 
             val repository = DefaultSynchronizerFactory.defaultDerivedDataRepository(
-                applicationContext,
-                backend,
-                coordinator.dataDbFile(zcashNetwork, alias),
-                zcashNetwork,
-                loadedCheckpoint,
-                seed,
-                viewingKeys
+                context = applicationContext,
+                rustBackend = backend,
+                databaseFile = coordinator.dataDbFile(zcashNetwork, alias),
+                zcashNetwork = zcashNetwork,
+                checkpoint = loadedCheckpoint,
+                seed = seed,
+                numberOfAccounts = Derivation.DEFAULT_NUMBER_OF_ACCOUNTS,
+                recoverUntil = chainTip,
             )
 
-            val service = DefaultSynchronizerFactory.defaultService(applicationContext, lightWalletEndpoint)
             val encoder = DefaultSynchronizerFactory.defaultEncoder(backend, saplingParamTool, repository)
-            val downloader = DefaultSynchronizerFactory.defaultDownloader(service, blockStore)
             val txManager = DefaultSynchronizerFactory.defaultTxManager(
                 encoder,
                 service
             )
             val processor = DefaultSynchronizerFactory.defaultProcessor(
-                backend,
-                downloader,
-                repository,
-                birthday
-                    ?: zcashNetwork.saplingActivationHeight
+                backend = backend,
+                downloader = downloader,
+                repository = repository,
+                birthdayHeight = birthday ?: zcashNetwork.saplingActivationHeight
             )
 
             return SdkSynchronizer.new(
-                zcashNetwork,
-                alias,
-                repository,
-                txManager,
-                processor,
-                backend
+                zcashNetwork = zcashNetwork,
+                alias = alias,
+                repository = repository,
+                txManager = txManager,
+                processor = processor,
+                backend = backend
             )
         }
 
@@ -513,9 +550,10 @@ interface Synchronizer {
             alias: String = ZcashSdk.DEFAULT_ALIAS,
             lightWalletEndpoint: LightWalletEndpoint,
             seed: ByteArray?,
-            birthday: BlockHeight?
+            birthday: BlockHeight?,
+            walletInitMode: WalletInitMode
         ): CloseableSynchronizer = runBlocking {
-            new(context, zcashNetwork, alias, lightWalletEndpoint, seed, birthday)
+            new(context, zcashNetwork, alias, lightWalletEndpoint, seed, birthday, walletInitMode)
         }
 
         /**
@@ -540,6 +578,23 @@ interface Synchronizer {
     }
 }
 
+/**
+ * Sealed class describing wallet initialization mode.
+ *
+ * Use [NewWallet] type if the seed was just created as part of a
+ * new wallet initialization.
+ *
+ * Use [RestoreWallet] type if an existed wallet is initialized
+ * from a restored seed with older birthday height.
+ *
+ * Use [ExistingWallet] type if the wallet is already initialized.
+ */
+sealed class WalletInitMode {
+    data object NewWallet : WalletInitMode()
+    data object RestoreWallet : WalletInitMode()
+    data object ExistingWallet : WalletInitMode()
+}
+
 interface CloseableSynchronizer : Synchronizer, Closeable
 
 /**
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/CompactBlockProcessor.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessor.kt
similarity index 52%
rename from sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/CompactBlockProcessor.kt
rename to sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessor.kt
index 39323eb1..3287be24 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/CompactBlockProcessor.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessor.kt
@@ -1,8 +1,19 @@
-package cash.z.ecc.android.sdk.block
+package cash.z.ecc.android.sdk.block.processor
 
 import androidx.annotation.VisibleForTesting
 import cash.z.ecc.android.sdk.BuildConfig
 import cash.z.ecc.android.sdk.annotation.OpenForTesting
+import cash.z.ecc.android.sdk.block.processor.model.BatchSyncProgress
+import cash.z.ecc.android.sdk.block.processor.model.GetMaxScannedHeightResult
+import cash.z.ecc.android.sdk.block.processor.model.GetScanProgressResult
+import cash.z.ecc.android.sdk.block.processor.model.GetSubtreeRootsResult
+import cash.z.ecc.android.sdk.block.processor.model.PutSaplingSubtreeRootsResult
+import cash.z.ecc.android.sdk.block.processor.model.SbSPreparationResult
+import cash.z.ecc.android.sdk.block.processor.model.SuggestScanRangesResult
+import cash.z.ecc.android.sdk.block.processor.model.SyncStageResult
+import cash.z.ecc.android.sdk.block.processor.model.SyncingResult
+import cash.z.ecc.android.sdk.block.processor.model.UpdateChainTipResult
+import cash.z.ecc.android.sdk.block.processor.model.VerifySuggestedScanRange
 import cash.z.ecc.android.sdk.exception.CompactBlockProcessorException
 import cash.z.ecc.android.sdk.exception.CompactBlockProcessorException.EnhanceTransactionError.EnhanceTxDecryptError
 import cash.z.ecc.android.sdk.exception.CompactBlockProcessorException.EnhanceTransactionError.EnhanceTxDownloadError
@@ -17,13 +28,18 @@ import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.internal.TypesafeBackend
 import cash.z.ecc.android.sdk.internal.block.CompactBlockDownloader
 import cash.z.ecc.android.sdk.internal.ext.isNullOrEmpty
+import cash.z.ecc.android.sdk.internal.ext.isScanContinuityError
 import cash.z.ecc.android.sdk.internal.ext.length
-import cash.z.ecc.android.sdk.internal.ext.retryUpTo
+import cash.z.ecc.android.sdk.internal.ext.retryUpToAndContinue
+import cash.z.ecc.android.sdk.internal.ext.retryUpToAndThrow
 import cash.z.ecc.android.sdk.internal.ext.retryWithBackoff
 import cash.z.ecc.android.sdk.internal.ext.toHexReversed
 import cash.z.ecc.android.sdk.internal.model.BlockBatch
 import cash.z.ecc.android.sdk.internal.model.DbTransactionOverview
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.internal.model.ScanRange
+import cash.z.ecc.android.sdk.internal.model.SubtreeRoot
+import cash.z.ecc.android.sdk.internal.model.SuggestScanRangePriority
 import cash.z.ecc.android.sdk.internal.model.ext.from
 import cash.z.ecc.android.sdk.internal.model.ext.toBlockHeight
 import cash.z.ecc.android.sdk.internal.repository.DerivedDataRepository
@@ -32,12 +48,12 @@ import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.PercentDecimal
 import cash.z.ecc.android.sdk.model.WalletBalance
 import cash.z.ecc.android.sdk.model.ZcashNetwork
-import co.electriccoin.lightwallet.client.ext.BenchmarkingExt
-import co.electriccoin.lightwallet.client.fixture.BenchmarkingBlockRangeFixture
 import co.electriccoin.lightwallet.client.model.BlockHeightUnsafe
 import co.electriccoin.lightwallet.client.model.GetAddressUtxosReplyUnsafe
 import co.electriccoin.lightwallet.client.model.LightWalletEndpointInfoUnsafe
 import co.electriccoin.lightwallet.client.model.Response
+import co.electriccoin.lightwallet.client.model.ShieldedProtocolEnum
+import co.electriccoin.lightwallet.client.model.SubtreeRootUnsafe
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -51,15 +67,16 @@ import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.onCompletion
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.flow.takeWhile
+import kotlinx.coroutines.flow.toList
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import java.util.Locale
 import java.util.concurrent.atomic.AtomicInteger
 import kotlin.math.max
 import kotlin.math.min
-import kotlin.math.roundToInt
 import kotlin.time.Duration
 import kotlin.time.Duration.Companion.days
+import kotlin.time.Duration.Companion.minutes
 import kotlin.time.DurationUnit
 import kotlin.time.toDuration
 
@@ -127,8 +144,14 @@ class CompactBlockProcessor internal constructor(
 
     private val _state: MutableStateFlow<State> = MutableStateFlow(State.Initialized)
     private val _progress = MutableStateFlow(PercentDecimal.ZERO_PERCENT)
-    private val _processorInfo = MutableStateFlow(ProcessorInfo(null, null, null, null))
+    private val _processorInfo = MutableStateFlow(ProcessorInfo(null, null, null))
     private val _networkHeight = MutableStateFlow<BlockHeight?>(null)
+
+    // pools
+    internal val saplingBalances = MutableStateFlow<WalletBalance?>(null)
+    internal val orchardBalances = MutableStateFlow<WalletBalance?>(null)
+    internal val transparentBalances = MutableStateFlow<WalletBalance?>(null)
+
     private val processingMutex = Mutex()
 
     /**
@@ -174,7 +197,7 @@ class CompactBlockProcessor internal constructor(
     /**
      * Download compact blocks, verify and scan them until [stop] is called.
      */
-    @Suppress("LongMethod")
+    @Suppress("LongMethod", "CyclomaticComplexMethod")
     suspend fun start() {
         verifySetup()
 
@@ -183,21 +206,94 @@ class CompactBlockProcessor internal constructor(
         // Clear any undeleted left over block files from previous sync attempts
         deleteAllBlockFiles(
             downloader = downloader,
-            lastKnownHeight = getLastScannedHeight(repository)
+            lastKnownHeight = when (val result = getMaxScannedHeight(backend)) {
+                is GetMaxScannedHeightResult.Success -> result.height
+                else -> null
+            }
         )
 
-        Twig.debug { "setup verified. processor starting" }
+        // Download note commitment tree data from lightwalletd to decide if we communicate with linear
+        // or spend-before-sync node.
+        var subTreeRootResult = getSubtreeRoots(downloader, network)
+        Twig.info { "Fetched SubTreeRoot result: $subTreeRootResult" }
 
-        // using do/while makes it easier to execute exactly one loop which helps with testing this processor quickly
+        Twig.debug { "Setup verified. Processor starting..." }
+
+        // Using do/while makes it easier to execute exactly one loop which helps with testing this processor quickly
         // (because you can start and then immediately set isStopped=true to always get precisely one loop)
         do {
-            retryWithBackoff(::onProcessorError, maxDelayMillis = MAX_BACKOFF_INTERVAL) {
+            retryWithBackoff(
+                onErrorListener = ::onProcessorError,
+                maxDelayMillis = MAX_BACKOFF_INTERVAL
+            ) {
                 val result = processingMutex.withLockLogged("processNewBlocks") {
-                    processNewBlocks()
+                    when (subTreeRootResult) {
+                        is GetSubtreeRootsResult.SpendBeforeSync -> {
+                            // Pass the commitment tree data to the database
+                            when (
+                                val result = putSaplingSubtreeRoots(
+                                    backend = backend,
+                                    startIndex = 0,
+                                    subTreeRootList = (subTreeRootResult as GetSubtreeRootsResult.SpendBeforeSync)
+                                        .subTreeRootList,
+                                    lastValidHeight = lowerBoundHeight
+                                )
+                            ) {
+                                PutSaplingSubtreeRootsResult.Success -> {
+                                    // Lets continue with the next step
+                                }
+                                is PutSaplingSubtreeRootsResult.Failure -> {
+                                    BlockProcessingResult.SyncFailure(result.failedAtHeight, result.exception)
+                                }
+                            }
+                            processNewBlocksInSbSOrder(
+                                backend = backend,
+                                downloader = downloader,
+                                repository = repository,
+                                network = network,
+                                lastValidHeight = lowerBoundHeight,
+                                firstUnenhancedHeight = _processorInfo.value.firstUnenhancedHeight
+                            )
+                        }
+                        GetSubtreeRootsResult.Linear -> {
+                            // This is caused by an empty response result. Although the spend-before-sync
+                            // synchronization algorithm is not supported, we can get the entire block range as we
+                            // previously did for the linear sync type.
+                            processNewBlocksInSbSOrder(
+                                backend = backend,
+                                downloader = downloader,
+                                repository = repository,
+                                network = network,
+                                lastValidHeight = lowerBoundHeight,
+                                firstUnenhancedHeight = _processorInfo.value.firstUnenhancedHeight
+                            )
+                        }
+                        is GetSubtreeRootsResult.OtherFailure -> {
+                            // The server possibly replied with some unsupported error. We still approach
+                            // spend-before-sync synchronization.
+                            processNewBlocksInSbSOrder(
+                                backend = backend,
+                                downloader = downloader,
+                                repository = repository,
+                                network = network,
+                                lastValidHeight = lowerBoundHeight,
+                                firstUnenhancedHeight = _processorInfo.value.firstUnenhancedHeight
+                            )
+                        }
+                        GetSubtreeRootsResult.FailureConnection -> {
+                            // SubtreeRoot fetching retry
+                            subTreeRootResult = getSubtreeRoots(downloader, network)
+                            BlockProcessingResult.Reconnecting
+                        }
+                    }
                 }
-                // immediately process again after failures in order to download new blocks right away
+
+                // Immediately process again after failures in order to download new blocks right away
                 when (result) {
                     BlockProcessingResult.Reconnecting -> {
+                        setState(State.Disconnected)
+                        downloader.reconnect()
+
                         val napTime = calculatePollInterval(true)
                         Twig.debug {
                             "Unable to process new blocks because we are disconnected! Attempting to " +
@@ -205,9 +301,13 @@ class CompactBlockProcessor internal constructor(
                         }
                         delay(napTime)
                     }
-
+                    BlockProcessingResult.RestartSynchronization -> {
+                        Twig.info { "Planned restarting of block synchronization..." }
+                        // No nap time set to immediately continue with refreshed block synchronization
+                    }
                     BlockProcessingResult.NoBlocksToProcess -> {
-                        val noWorkDone = _processorInfo.value.lastSyncRange?.isEmpty() ?: true
+                        setState(State.Synced(_processorInfo.value.overallSyncRange))
+                        val noWorkDone = _processorInfo.value.overallSyncRange?.isEmpty() ?: true
                         val summary = if (noWorkDone) {
                             "Nothing to process: no new blocks to sync"
                         } else {
@@ -221,49 +321,18 @@ class CompactBlockProcessor internal constructor(
                         }
                         delay(napTime)
                     }
-
-                    is BlockProcessingResult.FailedEnhance -> {
+                    is BlockProcessingResult.SyncFailure -> {
                         Twig.error {
-                            "Failed while enhancing transaction details at height: ${result.error.height} +" +
-                                "with: ${result.error}"
-                        }
-                        checkErrorResult(result.error.height)
-                    }
-
-                    is BlockProcessingResult.FailedDeleteBlocks -> {
-                        Twig.error {
-                            "Failed to delete temporary blocks files from the device disk. It will be retried on the" +
-                                " next time, while downloading new blocks."
+                            "Failed while processing blocks at height: ${result.failedAtHeight} with: " +
+                                "${result.error}"
                         }
+                        // TODO [#1222]: Enrich BlockProcessingResult.SyncFailure with root cause
+                        // TODO [#1222]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1222
                         checkErrorResult(result.failedAtHeight)
                     }
-
-                    is BlockProcessingResult.FailedDownloadBlocks -> {
-                        Twig.error { "Failed while downloading blocks at height: ${result.failedAtHeight}" }
-                        checkErrorResult(result.failedAtHeight)
-                    }
-
-                    is BlockProcessingResult.FailedValidateBlocks -> {
-                        Twig.error { "Failed while validating blocks at height: ${result.failedAtHeight}" }
-                        checkErrorResult(result.failedAtHeight)
-                    }
-
-                    is BlockProcessingResult.FailedScanBlocks -> {
-                        Twig.error { "Failed while scanning blocks at height: ${result.failedAtHeight}" }
-                        checkErrorResult(result.failedAtHeight)
-                    }
-
                     is BlockProcessingResult.Success -> {
                         // Do nothing.
                     }
-
-                    is BlockProcessingResult.DownloadSuccess -> {
-                        // Do nothing. Syncing of blocks is in progress.
-                    }
-
-                    BlockProcessingResult.UpdateBirthday -> {
-                        // Do nothing. The birthday was just updated.
-                    }
                 }
             }
         } while (_state.value !is State.Stopped)
@@ -271,7 +340,7 @@ class CompactBlockProcessor internal constructor(
         stop()
     }
 
-    suspend fun checkErrorResult(failedHeight: BlockHeight) {
+    suspend fun checkErrorResult(failedHeight: BlockHeight?) {
         if (consecutiveChainErrors.get() >= RETRIES) {
             val errorMessage = "ERROR: unable to resolve reorg at height $failedHeight after " +
                 "${consecutiveChainErrors.get()} correction attempts!"
@@ -301,149 +370,396 @@ class CompactBlockProcessor internal constructor(
         throw error
     }
 
-    private suspend fun processNewBlocks(): BlockProcessingResult {
-        Twig.debug { "Beginning to process new blocks (with lower bound: $lowerBoundHeight)..." }
+    // TODO [#1137]: Refactor processNewBlocksInSbSOrder
+    // TODO [#1137]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1137
+    /**
+     * This function process the missing blocks in non-linear order with Spend-before-Sync algorithm.
+     */
+    @Suppress("ReturnCount", "LongMethod", "CyclomaticComplexMethod", "LongParameterList")
+    private suspend fun processNewBlocksInSbSOrder(
+        backend: TypesafeBackend,
+        downloader: CompactBlockDownloader,
+        repository: DerivedDataRepository,
+        network: ZcashNetwork,
+        lastValidHeight: BlockHeight,
+        firstUnenhancedHeight: BlockHeight?
+    ): BlockProcessingResult {
+        Twig.info {
+            "Beginning to process new blocks with Spend-before-Sync approach with lower bound: $lastValidHeight)..."
+        }
 
-        return if (!updateRanges()) {
-            Twig.debug { "Disconnection detected! Attempting to reconnect!" }
-            setState(State.Disconnected)
-            downloader.lightWalletClient.reconnect()
-            BlockProcessingResult.Reconnecting
-        } else if (_processorInfo.value.lastSyncRange.isNullOrEmpty()) {
-            setState(State.Synced(_processorInfo.value.lastSyncRange))
-            BlockProcessingResult.NoBlocksToProcess
-        } else {
-            val syncRange = if (BenchmarkingExt.isBenchmarking()) {
-                // We inject a benchmark test blocks range at this point to process only a restricted range of
-                // blocks for a more reliable benchmark results.
-                val benchmarkBlockRange = BenchmarkingBlockRangeFixture.new().let {
-                    // Convert range of Longs to range of BlockHeights
-                    BlockHeight.new(ZcashNetwork.Mainnet, it.start)..(
-                        BlockHeight.new(ZcashNetwork.Mainnet, it.endInclusive)
-                        )
+        // This step covers these operations fetchLatestBlockHeight, updateChainTip, suggestScanRanges, updateRange,
+        // and shouldVerifySuggestedScanRanges
+        val preparationResult = runSbSSyncingPreparation(
+            backend = backend,
+            downloader = downloader,
+            network = network,
+            lastValidHeight = lastValidHeight
+        )
+        when (preparationResult) {
+            is SbSPreparationResult.ProcessFailure -> {
+                return preparationResult.toBlockProcessingResult()
+            }
+            SbSPreparationResult.ConnectionFailure -> {
+                return BlockProcessingResult.Reconnecting
+            }
+            SbSPreparationResult.NoMoreBlocksToProcess -> {
+                return BlockProcessingResult.NoBlocksToProcess
+            }
+            is SbSPreparationResult.Success -> {
+                Twig.info { "Preparation phase done with result: $preparationResult" }
+                // Continue processing ranges
+            }
+        }
+
+        var verifyRangeResult = preparationResult.verifyRangeResult
+        var suggestedRangesResult = preparationResult.suggestedRangesResult
+        val lastPreparationTime = System.currentTimeMillis()
+
+        // Running synchronization for the [ScanRange.SuggestScanRangePriority.Verify] range
+        while (verifyRangeResult is VerifySuggestedScanRange.ShouldVerify) {
+            Twig.info { "Starting verification of range: $verifyRangeResult" }
+
+            // Remove existing blocks as they'll be re-downloaded
+            downloader.rewindToHeight(verifyRangeResult.scanRange.range.start)
+            deleteAllBlockFiles(
+                downloader = downloader,
+                lastKnownHeight = verifyRangeResult.scanRange.range.start
+            )
+
+            var syncingResult: SyncingResult = SyncingResult.AllSuccess
+            runSyncingAndEnhancingOnRange(
+                backend = backend,
+                downloader = downloader,
+                repository = repository,
+                network = network,
+                syncRange = verifyRangeResult.scanRange.range,
+                withDownload = true,
+                enhanceStartHeight = firstUnenhancedHeight
+            ).collect { rangeSyncProgress ->
+                // Update sync progress
+                when (val result = getScanProgress(backend)) {
+                    is GetScanProgressResult.Success -> {
+                        val resultProgress = result.toPercentDecimal()
+                        Twig.info { "Progress from rust: ${resultProgress.decimal}" }
+                        setProgress(resultProgress)
+                    }
+                    else -> { /* Do not report the progress in case of any error */ }
+                }
+                checkAllBalances()
+
+                when (rangeSyncProgress.resultState) {
+                    SyncingResult.UpdateBirthday -> {
+                        updateBirthdayHeight()
+                    }
+                    SyncingResult.EnhanceSuccess -> {
+                        Twig.info { "Triggering transaction refresh now" }
+                        // Invalidate transaction data
+                        checkTransactions(transactionStorage = repository)
+                    }
+                    is SyncingResult.Failure -> {
+                        syncingResult = rangeSyncProgress.resultState
+                        return@collect
+                    } else -> {
+                        // Continue with processing
+                    }
                 }
-                benchmarkBlockRange
-            } else {
-                _processorInfo.value.lastSyncRange!!
             }
 
-            syncBlocksAndEnhanceTransactions(
-                syncRange = syncRange,
-                withDownload = true,
-                enhanceStartHeight = _processorInfo.value.firstUnenhancedHeight
-            )
+            when (syncingResult) {
+                is SyncingResult.AllSuccess -> {
+                    // Continue with processing the rest of the ranges
+                } else -> {
+                    // An error came - remove persisted but not scanned blocks
+                    val lastScannedHeight = when (val result = getMaxScannedHeight(backend)) {
+                        is GetMaxScannedHeightResult.Success -> result.height
+                        else -> null
+                    }
+                    lastScannedHeight?.let {
+                        downloader.rewindToHeight(lastScannedHeight)
+                    }
+                    deleteAllBlockFiles(
+                        downloader = downloader,
+                        lastKnownHeight = lastScannedHeight
+                    )
+                    return (syncingResult as SyncingResult.Failure).toBlockProcessingResult()
+                }
+            }
+
+            // Re-request suggested scan ranges
+            suggestedRangesResult = suggestScanRanges(backend, lowerBoundHeight)
+            when (suggestedRangesResult) {
+                is SuggestScanRangesResult.Success -> {
+                    verifyRangeResult = shouldVerifySuggestedScanRanges(suggestedRangesResult)
+                }
+                is SuggestScanRangesResult.Failure -> {
+                    Twig.error { "Process suggested scan ranges failure: ${suggestedRangesResult.exception}" }
+                    return BlockProcessingResult.SyncFailure(
+                        suggestedRangesResult.failedAtHeight,
+                        suggestedRangesResult.exception
+                    )
+                }
+            }
         }
+
+        // Process the rest of ranges
+        val scanRanges = when (suggestedRangesResult) {
+            is SuggestScanRangesResult.Success -> { suggestedRangesResult.ranges }
+            is SuggestScanRangesResult.Failure -> {
+                Twig.error { "Process suggested scan ranges failure: ${suggestedRangesResult.exception}" }
+                return BlockProcessingResult.SyncFailure(
+                    suggestedRangesResult.failedAtHeight,
+                    suggestedRangesResult.exception
+                )
+            }
+        }
+        scanRanges.forEach { scanRange ->
+            Twig.debug { "Start processing the range: $scanRange" }
+
+            // TODO [#1145]: Sync Historic range in reverse order
+            // TODO [#1145]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1145
+            var syncingResult: SyncingResult = SyncingResult.AllSuccess
+            runSyncingAndEnhancingOnRange(
+                backend = backend,
+                downloader = downloader,
+                repository = repository,
+                network = network,
+                syncRange = scanRange.range,
+                withDownload = true,
+                enhanceStartHeight = firstUnenhancedHeight
+            ).map { rangeSyncProgress ->
+                // Update sync progress
+                when (val result = getScanProgress(backend)) {
+                    is GetScanProgressResult.Success -> {
+                        val resultProgress = result.toPercentDecimal()
+                        Twig.info { "Progress from rust: ${resultProgress.decimal}" }
+                        setProgress(resultProgress)
+                    }
+                    else -> { /* Do not report the progress in case of any error */ }
+                }
+                checkAllBalances()
+
+                when (rangeSyncProgress.resultState) {
+                    SyncingResult.UpdateBirthday -> {
+                        updateBirthdayHeight()
+                        SyncingResult.AllSuccess
+                    }
+                    SyncingResult.EnhanceSuccess -> {
+                        Twig.info { "Triggering transaction refresh now" }
+                        // Invalidate transaction data and return the common batch syncing success result to the caller
+                        checkTransactions(transactionStorage = repository)
+                        SyncingResult.AllSuccess
+                    }
+                    is SyncingResult.Failure -> {
+                        rangeSyncProgress.resultState
+                    } else -> {
+                        // First, check the time and refresh the prepare phase inputs, if needed
+                        val currentTimeMillis = System.currentTimeMillis()
+                        if (shouldRefreshPreparation(
+                                lastPreparationTime,
+                                currentTimeMillis,
+                                SYNCHRONIZATION_RESTART_TIMEOUT
+                            )
+                        ) {
+                            SyncingResult.RestartSynchronization
+                        } else {
+                            // Continue with processing
+                            SyncingResult.AllSuccess
+                        }
+                    }
+                }
+            }.takeWhile {
+                syncingResult = it
+                it == SyncingResult.AllSuccess
+            }.collect()
+
+            when (syncingResult) {
+                is SyncingResult.AllSuccess -> {
+                    // Continue with processing the rest of the ranges
+                }
+                is SyncingResult.RestartSynchronization -> {
+                    // Restarting the synchronization process
+                    return BlockProcessingResult.RestartSynchronization
+                } else -> {
+                    // An error came - remove persisted but not scanned blocks
+                    val lastScannedHeight = when (val result = getMaxScannedHeight(backend)) {
+                        is GetMaxScannedHeightResult.Success -> result.height
+                        else -> null
+                    }
+                    lastScannedHeight?.let {
+                        downloader.rewindToHeight(lastScannedHeight)
+                    }
+                    deleteAllBlockFiles(
+                        downloader = downloader,
+                        lastKnownHeight = lastScannedHeight
+                    )
+                    return (syncingResult as SyncingResult.Failure).toBlockProcessingResult()
+                }
+            }
+        }
+        return BlockProcessingResult.Success
     }
 
     @Suppress("ReturnCount")
-    private suspend fun syncBlocksAndEnhanceTransactions(
-        syncRange: ClosedRange<BlockHeight>,
-        withDownload: Boolean,
-        enhanceStartHeight: BlockHeight?
-    ): BlockProcessingResult {
-        _state.value = State.Syncing
-
-        // Syncing last blocks and enhancing transactions
-        var syncResult: BlockProcessingResult = BlockProcessingResult.Success
-        runSyncingAndEnhancing(
-            backend = backend,
+    internal suspend fun runSbSSyncingPreparation(
+        backend: TypesafeBackend,
+        downloader: CompactBlockDownloader,
+        network: ZcashNetwork,
+        lastValidHeight: BlockHeight
+    ): SbSPreparationResult {
+        // Download chain tip metadata from lightwalletd
+        val chainTip = fetchLatestBlockHeight(
             downloader = downloader,
-            repository = repository,
-            network = network,
-            syncRange = syncRange,
-            withDownload = withDownload,
-            enhanceStartHeight = enhanceStartHeight
-        ).collect { syncProgress ->
-            _progress.value = syncProgress.percentage
-            updateProgress(lastSyncedHeight = syncProgress.lastSyncedHeight)
+            network = network
+        ) ?: let {
+            Twig.warn { "Disconnection detected. Attempting to reconnect." }
+            return SbSPreparationResult.ConnectionFailure
+        }
 
-            if (syncProgress.result == BlockProcessingResult.UpdateBirthday) {
-                updateBirthdayHeight()
-            } else if (syncProgress.result != BlockProcessingResult.Success) {
-                syncResult = syncProgress.result
-                return@collect
+        // Notify the underlying rust layer about the updated chain tip
+        when (
+            val result =
+                updateChainTip(
+                    backend = backend,
+                    chainTip = chainTip,
+                    lastValidHeight = lastValidHeight
+                )
+        ) {
+            is UpdateChainTipResult.Success -> { /* Lets continue to the next step */ }
+            is UpdateChainTipResult.Failure -> {
+                return SbSPreparationResult.ProcessFailure(
+                    result.failedAtHeight,
+                    result.exception
+                )
             }
         }
 
-        if (syncResult != BlockProcessingResult.Success) {
-            // Remove persisted but not validated and scanned blocks in case of any failure
-            val lastScannedHeight = getLastScannedHeight(repository)
-            downloader.rewindToHeight(lastScannedHeight)
-            deleteAllBlockFiles(
-                downloader = downloader,
-                lastKnownHeight = lastScannedHeight
-            )
+        // TODO [#1211]: Re-enable block synchronization benchmark test
+        // TODO [#1211]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1211
 
-            return syncResult
+        // Get the suggested scan ranges from the wallet database
+        val suggestedRangesResult = suggestScanRanges(
+            backend,
+            lastValidHeight
+        )
+        val updateRangeResult = when (suggestedRangesResult) {
+            is SuggestScanRangesResult.Success -> {
+                updateRange(suggestedRangesResult.ranges)
+            }
+            is SuggestScanRangesResult.Failure -> {
+                Twig.error { "Process suggested scan ranges failure: ${suggestedRangesResult.exception}" }
+                return SbSPreparationResult.ProcessFailure(
+                    suggestedRangesResult.failedAtHeight,
+                    suggestedRangesResult.exception
+                )
+            }
         }
 
-        return BlockProcessingResult.Success
+        if (!updateRangeResult) {
+            Twig.warn { "Disconnection detected. Attempting to reconnect." }
+            return SbSPreparationResult.ConnectionFailure
+        } else if (_processorInfo.value.overallSyncRange.isNullOrEmpty()) {
+            Twig.info { "No more blocks to process." }
+            return SbSPreparationResult.NoMoreBlocksToProcess
+        }
+
+        setState(State.Syncing)
+
+        // Parse and process ranges. If it recognizes a range with Priority.Verify, it runs the verification part.
+        val verifyRangeResult = shouldVerifySuggestedScanRanges(suggestedRangesResult)
+
+        Twig.info { "Check for verification of ranges resulted with: $verifyRangeResult" }
+
+        return SbSPreparationResult.Success(
+            suggestedRangesResult = suggestedRangesResult,
+            verifyRangeResult = verifyRangeResult
+        )
+    }
+
+    /**
+     * This invalidates transaction storage to trigger data refreshing for its subscribers.
+     */
+    private fun checkTransactions(transactionStorage: DerivedDataRepository) {
+        transactionStorage.invalidate()
+    }
+
+    /**
+     * Calculate the latest balances, based on the blocks that have been scanned and transmit this
+     * information into the related internal flows. Note that the Orchard balance is not supported.
+     */
+    internal suspend fun checkAllBalances() {
+        checkSaplingBalance()
+        checkTransparentBalance()
+        // TODO [#682]: refresh orchard balance
+        // TODO [#682]: https://github.com/zcash/zcash-android-wallet-sdk/issues/682
+    }
+
+    /**
+     * Calculate the latest Sapling balance, based on the blocks that have been scanned and transmit this
+     * information into the internal [saplingBalances] flow.
+     */
+    internal suspend fun checkSaplingBalance() {
+        Twig.debug { "Checking Sapling balance" }
+        saplingBalances.value = getBalanceInfo(Account.DEFAULT)
+    }
+
+    /**
+     * Calculate the latest Transparent balance, based on the blocks that have been scanned and transmit this
+     * information into the internal [transparentBalances] flow.
+     */
+    internal suspend fun checkTransparentBalance() {
+        Twig.debug { "Checking Transparent balance" }
+        transparentBalances.value = getUtxoCacheBalance(getTransparentAddress(backend, Account.DEFAULT))
     }
 
     sealed class BlockProcessingResult {
         object NoBlocksToProcess : BlockProcessingResult()
         object Success : BlockProcessingResult()
-        data class DownloadSuccess(val downloadedBlocks: List<JniBlockMeta>?) : BlockProcessingResult()
-        object UpdateBirthday : BlockProcessingResult()
         object Reconnecting : BlockProcessingResult()
-        data class FailedDownloadBlocks(val failedAtHeight: BlockHeight) : BlockProcessingResult()
-        data class FailedScanBlocks(val failedAtHeight: BlockHeight) : BlockProcessingResult()
-        data class FailedValidateBlocks(val failedAtHeight: BlockHeight) : BlockProcessingResult()
-        data class FailedDeleteBlocks(val failedAtHeight: BlockHeight) : BlockProcessingResult()
-        data class FailedEnhance(val error: CompactBlockProcessorException.EnhanceTransactionError) :
-            BlockProcessingResult()
+        object RestartSynchronization : BlockProcessingResult()
+
+        // TODO [#1222]: Enrich BlockProcessingResult.SyncFailure with root cause
+        // TODO [#1222]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1222
+        data class SyncFailure(val failedAtHeight: BlockHeight?, val error: Throwable) : BlockProcessingResult()
     }
 
     /**
      * Gets the latest range info and then uses that initialInfo to update (and transmit)
-     * the scan/download ranges that require processing.
+     * the info that require processing.
+     *
+     * @param ranges The ranges which we obtained from the rust layer to proceed
      *
      * @return true when the update succeeds.
      */
-    private suspend fun updateRanges(): Boolean {
+    private suspend fun updateRange(ranges: List<ScanRange>): Boolean {
         // This fetches the latest height each time this method is called, which can be very inefficient
         // when downloading all of the blocks from the server
-        val networkBlockHeight = run {
-            val networkBlockHeightUnsafe =
-                when (val response = downloader.getLatestBlockHeight()) {
-                    is Response.Success -> response.result
-                    else -> null
-                }
-
-            runCatching { networkBlockHeightUnsafe?.toBlockHeight(network) }.getOrNull()
-        } ?: return false
-
-        // If we find out that we previously downloaded, but not validated and scanned persisted blocks, we need
-        // to rewind the blocks above the last scanned height first.
-        val lastScannedHeight = getLastScannedHeight(repository)
-        val lastDownloadedHeight = getLastDownloadedHeight(downloader).let {
-            BlockHeight.new(
-                network,
-                max(
-                    it?.value ?: 0,
-                    lowerBoundHeight.value
-                )
-            )
-        }
-        val lastSyncedHeight = if (lastDownloadedHeight.value - lastScannedHeight.value > 0) {
-            Twig.verbose {
-                "Clearing blocks of last persisted batch within the last scanned height " +
-                    "$lastScannedHeight and last download height $lastDownloadedHeight, as all these blocks " +
-                    "possibly haven't been validated and scanned in the previous blocks sync attempt."
-            }
-            downloader.rewindToHeight(lastScannedHeight)
-            lastScannedHeight
-        } else {
-            lastDownloadedHeight
-        }
+        val networkBlockHeight = fetchLatestBlockHeight(downloader, network) ?: return false
 
         // Get the first un-enhanced transaction from the repository
         val firstUnenhancedHeight = getFirstUnenhancedHeight(repository)
 
-        updateProgress(
+        // The overall sync range computation
+        val syncRange = if (ranges.isNotEmpty()) {
+            var resultRange = ranges[0].range.start..ranges[0].range.endInclusive
+            ranges.forEach { nextRange ->
+                if (nextRange.range.start < resultRange.start) {
+                    resultRange = nextRange.range.start..resultRange.endInclusive
+                }
+                if (nextRange.range.endInclusive > resultRange.endInclusive) {
+                    resultRange = resultRange.start..nextRange.range.endInclusive
+                }
+            }
+            resultRange
+        } else {
+            // Empty ranges most likely means that the sync is done and the Rust layer replied with an empty suggested
+            // ranges
+            null
+        }
+
+        setProcessorInfo(
             networkBlockHeight = networkBlockHeight,
-            lastSyncedHeight = lastSyncedHeight,
-            lastSyncRange = lastSyncedHeight + 1..networkBlockHeight,
+            overallSyncRange = syncRange,
             firstUnenhancedHeight = firstUnenhancedHeight
         )
 
@@ -453,13 +769,12 @@ class CompactBlockProcessor internal constructor(
     /**
      * Confirm that the wallet data is properly setup for use.
      */
-    // Need to refactor this to be less ugly and more testable
+    // TODO [#1127]: Refactor CompactBlockProcessor.verifySetup
+    // TODO [#1127]: Need to refactor this to be less ugly and more testable
+    // TODO [#1127]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1127
     @Suppress("NestedBlockDepth")
     private suspend fun verifySetup() {
-        // verify that the data is initialized
-        val error = if (!repository.isInitialized()) {
-            CompactBlockProcessorException.Uninitialized
-        } else if (repository.getAccountCount() == 0) {
+        val error = if (repository.getAccountCount() == 0) {
             CompactBlockProcessorException.NoAccount
         } else {
             // verify that the server is correct
@@ -532,10 +847,10 @@ class CompactBlockProcessor internal constructor(
         if (failedUtxoFetches < 9) { // there are 3 attempts per block
             @Suppress("TooGenericExceptionCaught")
             try {
-                retryUpTo(UTXO_FETCH_RETRIES) {
+                retryUpToAndThrow(UTXO_FETCH_RETRIES) {
                     val tAddresses = backend.listTransparentReceivers(account)
 
-                    downloader.lightWalletClient.fetchUtxos(
+                    downloader.fetchUtxos(
                         tAddresses,
                         BlockHeightUnsafe.from(startHeight)
                     ).onEach { response ->
@@ -646,6 +961,16 @@ class CompactBlockProcessor internal constructor(
          */
         internal const val UTXO_FETCH_RETRIES = 3
 
+        /**
+         * Latest block height fetching default attempts at retrying.
+         */
+        internal const val FETCH_LATEST_BLOCK_HEIGHT_RETRIES = 3
+
+        /**
+         * Get subtree roots default attempts at retrying.
+         */
+        internal const val GET_SUBTREE_ROOTS_RETRIES = 3
+
         /**
          * The theoretical maximum number of blocks in a reorg, due to other bottlenecks in the protocol design.
          */
@@ -653,11 +978,11 @@ class CompactBlockProcessor internal constructor(
 
         /**
          * Default size of batches of blocks to request from the compact block service. Then it's also used as a default
-         * size of batches of blocks to validate and scan via librustzcash. For scanning action applies this - the
-         * smaller this number the more granular information can be provided about scan state. Unfortunately, it may
-         * also lead to a lot of overhead during scanning.
+         * size of batches of blocks to scan via librustzcash. For scanning action applies this - the smaller this
+         * number the more granular information can be provided about scan state. Unfortunately, it may also lead to
+         * a lot of overhead during scanning.
          */
-        internal const val SYNC_BATCH_SIZE = 10
+        internal const val SYNC_BATCH_SIZE = 100
 
         /**
          * Default size of batch of blocks for running the transaction enhancing.
@@ -670,6 +995,268 @@ class CompactBlockProcessor internal constructor(
          */
         internal const val REWIND_DISTANCE = 10
 
+        /**
+         * Limit millis value for restarting currently running block synchronization.
+         */
+        internal val SYNCHRONIZATION_RESTART_TIMEOUT = 10.minutes.inWholeMilliseconds
+
+        /**
+         * Check for the next restart of the block synchronization preparation phase. This function is only SbS
+         * synchronization algorithm-related.
+         */
+        internal fun shouldRefreshPreparation(
+            lastPreparationTime: Long,
+            currentTimeMillis: Long,
+            limitTime: Long
+        ): Boolean {
+            return (currentTimeMillis - lastPreparationTime) >= limitTime
+        }
+
+        /**
+         * This operation fetches and returns the latest block height (chain tip)
+         *
+         * @return Latest block height wrapped in BlockHeight object, or null in case of failure
+         */
+        @VisibleForTesting
+        internal suspend fun fetchLatestBlockHeight(
+            downloader: CompactBlockDownloader,
+            network: ZcashNetwork
+        ): BlockHeight? {
+            Twig.debug { "Fetching latest block height..." }
+
+            var latestBlockHeight: BlockHeight? = null
+
+            retryUpToAndContinue(FETCH_LATEST_BLOCK_HEIGHT_RETRIES) {
+                when (val response = downloader.getLatestBlockHeight()) {
+                    is Response.Success -> {
+                        Twig.debug { "Latest block height fetched successfully with value: ${response.result.value}" }
+                        latestBlockHeight = runCatching {
+                            response.result.toBlockHeight(network)
+                        }.getOrNull()
+                    }
+                    is Response.Failure -> {
+                        Twig.error { "Fetching latest block height failed with: ${response.toThrowable()}" }
+                        throw LightWalletException.GetLatestBlockHeightException(
+                            response.code,
+                            response.description,
+                            response.toThrowable()
+                        )
+                    }
+                }
+            }
+
+            return latestBlockHeight
+        }
+
+        /**
+         * This operation downloads note commitment tree data from the lightwalletd server to decide if we communicate
+         * with linear or spend-before-sync node
+         *
+         * @return GetSubtreeRootsResult as a wrapper for the lightwalletd response result
+         */
+        @VisibleForTesting
+        internal suspend fun getSubtreeRoots(
+            downloader: CompactBlockDownloader,
+            network: ZcashNetwork
+        ): GetSubtreeRootsResult {
+            Twig.debug { "Fetching SubtreeRoots..." }
+
+            var result: GetSubtreeRootsResult = GetSubtreeRootsResult.Linear
+
+            retryUpToAndContinue(GET_SUBTREE_ROOTS_RETRIES) {
+                downloader.getSubtreeRoots(
+                    startIndex = 0,
+                    maxEntries = if (network.isTestnet()) {
+                        65536
+                    } else {
+                        0
+                    },
+                    shieldedProtocol = ShieldedProtocolEnum.SAPLING
+                ).onEach { response ->
+                    when (response) {
+                        is Response.Success -> {
+                            Twig.verbose {
+                                "SubtreeRoot got successfully: it's completingHeight: ${response.result
+                                    .completingBlockHeight}"
+                            }
+                        }
+                        is Response.Failure -> {
+                            val error = LightWalletException.GetSubtreeRootsException(
+                                response.code,
+                                response.description,
+                                response.toThrowable()
+                            )
+                            if (response is Response.Failure.Server.Unavailable) {
+                                Twig.error {
+                                    "Fetching SubtreeRoot failed due to server communication problem with " +
+                                        "failure: ${response.toThrowable()}"
+                                }
+                                result = GetSubtreeRootsResult.FailureConnection
+                            } else {
+                                Twig.error { "Fetching SubtreeRoot failed with failure: ${response.toThrowable()}" }
+                                result = GetSubtreeRootsResult.OtherFailure(error)
+                            }
+                            throw error
+                        }
+                    }
+                }
+                    .filterIsInstance<Response.Success<SubtreeRootUnsafe>>()
+                    .map { response ->
+                        response.result
+                    }
+                    .toList()
+                    .map {
+                        SubtreeRoot.new(it, network)
+                    }.let {
+                        result = if (it.isEmpty()) {
+                            GetSubtreeRootsResult.Linear
+                        } else {
+                            GetSubtreeRootsResult.SpendBeforeSync(it)
+                        }
+                    }
+            }
+            return result
+        }
+
+        /**
+         * Pass the commitment tree data to the database.
+         *
+         * @param backend Typesafe Rust backend
+         * @param startIndex Index to which put the data
+         * @param lastValidHeight The height to which rewind in case of any trouble
+         * @return PutSaplingSubtreeRootsResult
+         */
+        @VisibleForTesting
+        internal suspend fun putSaplingSubtreeRoots(
+            backend: TypesafeBackend,
+            startIndex: Long = 0,
+            subTreeRootList: List<SubtreeRoot>,
+            lastValidHeight: BlockHeight
+        ): PutSaplingSubtreeRootsResult {
+            return runCatching {
+                backend.putSaplingSubtreeRoots(
+                    startIndex = startIndex,
+                    roots = subTreeRootList
+                )
+            }
+                .onSuccess {
+                    Twig.info {
+                        "Sapling subtree roots put successfully with startIndex: $startIndex and roots: " +
+                            "${subTreeRootList.size}"
+                    }
+                }
+                .onFailure {
+                    Twig.error { "Sapling subtree roots put failed with: $it" }
+                }.fold(
+                    onSuccess = { PutSaplingSubtreeRootsResult.Success },
+                    onFailure = { PutSaplingSubtreeRootsResult.Failure(lastValidHeight, it) }
+                )
+        }
+
+        /**
+         * Notify the wallet of the updated chain tip.
+         *
+         * @param backend Typesafe Rust backend
+         * @param chainTip Height of latest block
+         * @param lastValidHeight The height to which rewind in case of any trouble
+         * @return UpdateChainTipResult
+         */
+        @VisibleForTesting
+        internal suspend fun updateChainTip(
+            backend: TypesafeBackend,
+            chainTip: BlockHeight,
+            lastValidHeight: BlockHeight
+        ): UpdateChainTipResult {
+            return runCatching {
+                backend.updateChainTip(chainTip)
+            }
+                .onSuccess {
+                    Twig.info { "Chain tip updated successfully with height: $chainTip" }
+                }
+                .onFailure {
+                    Twig.info { "Chain tip update failed with: $it" }
+                }.fold(
+                    onSuccess = { UpdateChainTipResult.Success(chainTip) },
+                    onFailure = { UpdateChainTipResult.Failure(lastValidHeight, it) }
+                )
+        }
+
+        /**
+         * Get the suggested scan ranges from the wallet database via the rust layer.
+         *
+         * @param backend Typesafe Rust backend
+         * @param lastValidHeight The height to which rewind in case of any trouble
+         * @return SuggestScanRangesResult
+         */
+        @VisibleForTesting
+        internal suspend fun suggestScanRanges(
+            backend: TypesafeBackend,
+            lastValidHeight: BlockHeight
+        ): SuggestScanRangesResult {
+            return runCatching {
+                backend.suggestScanRanges()
+            }.onSuccess { ranges ->
+                Twig.info { "Successfully got newly suggested ranges: $ranges" }
+            }.onFailure { exception ->
+                Twig.error { "Failed to get newly suggested ranges with: $exception" }
+            }.fold(
+                onSuccess = { SuggestScanRangesResult.Success(it) },
+                onFailure = { SuggestScanRangesResult.Failure(lastValidHeight, it) }
+            )
+        }
+
+        /**
+         * Parse and process ranges. If it recognizes a range with Priority.Verify at the first position, it runs the
+         * verification part.
+         *
+         * @param suggestedRangesResult Wrapper for list of ranges to process
+         * @return VerifySuggestedScanRange
+         */
+        @VisibleForTesting
+        internal fun shouldVerifySuggestedScanRanges(
+            suggestedRangesResult: SuggestScanRangesResult.Success
+        ): VerifySuggestedScanRange {
+            Twig.debug { "Check for Priority.Verify scan range result: ${suggestedRangesResult.ranges}" }
+
+            return if (suggestedRangesResult.ranges.isEmpty()) {
+                VerifySuggestedScanRange.NoRangeToVerify
+            } else {
+                val firstRangePriority = suggestedRangesResult.ranges[0].getSuggestScanRangePriority()
+                if (firstRangePriority == SuggestScanRangePriority.Verify) {
+                    VerifySuggestedScanRange.ShouldVerify(suggestedRangesResult.ranges[0])
+                } else {
+                    VerifySuggestedScanRange.NoRangeToVerify
+                }
+            }
+        }
+
+        /**
+         * Get the current block scanning progress.
+         *
+         * @return the last scanning progress calculated by the Rust layer and wrapped in [GetScanProgressResult]
+         */
+        @VisibleForTesting
+        internal suspend fun getScanProgress(backend: TypesafeBackend): GetScanProgressResult {
+            return runCatching {
+                backend.getScanProgress()
+            }.onSuccess {
+                Twig.verbose { "Successfully called getScanProgress with result: $it" }
+            }.onFailure {
+                Twig.error { "Failed to call getScanProgress with result: $it" }
+            }.fold(
+                onSuccess = {
+                    if (it == null) {
+                        GetScanProgressResult.None
+                    } else {
+                        GetScanProgressResult.Success(it)
+                    }
+                },
+                onFailure = {
+                    GetScanProgressResult.Failure(it)
+                }
+            )
+        }
+
         /**
          * Requests, processes and persists all blocks from the given range.
          *
@@ -682,31 +1269,31 @@ class CompactBlockProcessor internal constructor(
          * processed existing blocks
          * @param enhanceStartHeight the height in which the enhancing should start, or null in case of no previous
          * transaction enhancing done yet
+         * @param lastBatchOrder is the order of the last processed batch. It comes from a previous range processing
+         * and is necessary for calculating cross ranges batch order of currently processing batches.
 
-         * @return Flow of BatchSyncProgress sync and enhancement results
+         * @return Flow of [BatchSyncProgress] sync and enhancement results
          */
         @VisibleForTesting
         @Suppress("LongParameterList", "LongMethod")
-        internal suspend fun runSyncingAndEnhancing(
+        internal suspend fun runSyncingAndEnhancingOnRange(
             backend: TypesafeBackend,
             downloader: CompactBlockDownloader,
             repository: DerivedDataRepository,
             network: ZcashNetwork,
             syncRange: ClosedRange<BlockHeight>,
             withDownload: Boolean,
-            enhanceStartHeight: BlockHeight?,
+            enhanceStartHeight: BlockHeight?
         ): Flow<BatchSyncProgress> = flow {
             if (syncRange.isEmpty()) {
                 Twig.debug { "No blocks to sync" }
                 emit(
                     BatchSyncProgress(
-                        percentage = PercentDecimal.ONE_HUNDRED_PERCENT,
-                        lastSyncedHeight = getLastScannedHeight(repository),
-                        result = BlockProcessingResult.Success
+                        resultState = SyncingResult.AllSuccess
                     )
                 )
             } else {
-                Twig.debug { "Syncing blocks in range $syncRange" }
+                Twig.info { "Syncing blocks in range $syncRange" }
 
                 val batches = getBatchedBlockList(syncRange, network)
 
@@ -729,47 +1316,32 @@ class CompactBlockProcessor internal constructor(
                                 batch = it
                             )
                         } else {
-                            BlockProcessingResult.DownloadSuccess(null)
+                            SyncingResult.DownloadSuccess(null)
                         }
                     )
                 }.buffer(1).map { downloadStageResult ->
                     Twig.debug { "Download stage done with result: $downloadStageResult" }
 
-                    if (downloadStageResult.stageResult !is BlockProcessingResult.DownloadSuccess) {
+                    if (downloadStageResult.stageResult !is SyncingResult.DownloadSuccess) {
                         // In case of any failure, we just propagate the result
                         downloadStageResult
                     } else {
                         // Enrich batch model with fetched blocks. It's useful for later blocks deletion
                         downloadStageResult.batch.blocks = downloadStageResult.stageResult.downloadedBlocks
 
-                        // Run validation stage
+                        // Run scanning stage (which also validates the fetched blocks)
                         SyncStageResult(
                             downloadStageResult.batch,
-                            validateBatchOfBlocks(
-                                backend = backend,
-                                batch = downloadStageResult.batch
-                            )
-                        )
-                    }
-                }.map { validateResult ->
-                    Twig.debug { "Validation stage done with result: $validateResult" }
-
-                    if (validateResult.stageResult != BlockProcessingResult.Success) {
-                        validateResult
-                    } else {
-                        // Run scanning stage
-                        SyncStageResult(
-                            validateResult.batch,
                             scanBatchOfBlocks(
                                 backend = backend,
-                                batch = validateResult.batch
+                                batch = downloadStageResult.batch
                             )
                         )
                     }
                 }.map { scanResult ->
                     Twig.debug { "Scan stage done with result: $scanResult" }
 
-                    if (scanResult.stageResult != BlockProcessingResult.Success) {
+                    if (scanResult.stageResult != SyncingResult.ScanSuccess) {
                         scanResult
                     } else {
                         // Run deletion stage
@@ -784,21 +1356,26 @@ class CompactBlockProcessor internal constructor(
                 }.onEach { continuousResult ->
                     Twig.debug { "Deletion stage done with result: $continuousResult" }
 
+                    var resultState = if (continuousResult.stageResult == SyncingResult.DeleteSuccess) {
+                        SyncingResult.AllSuccess
+                    } else {
+                        continuousResult.stageResult
+                    }
+
                     emit(
                         BatchSyncProgress(
-                            percentage = PercentDecimal(continuousResult.batch.order / batches.size.toFloat()),
-                            lastSyncedHeight = getLastScannedHeight(repository),
-                            result = continuousResult.stageResult
+                            order = continuousResult.batch.order,
+                            resultState = resultState
                         )
                     )
 
                     // Increment and compare the range for triggering the enhancing
                     enhancingRange = enhancingRange.start..continuousResult.batch.range.endInclusive
 
-                    // Enhance is run in case of the range is on or over its limit, or in case of any failure
+                    // Enhancing is run in case of the range is on or over its limit, or in case of any failure
                     // state comes from the previous stages, or if the end of the sync range is reached
                     if (enhancingRange.length() >= ENHANCE_BATCH_SIZE ||
-                        continuousResult.stageResult != BlockProcessingResult.Success ||
+                        resultState != SyncingResult.AllSuccess ||
                         continuousResult.batch.order == batches.size.toLong()
                     ) {
                         // Copy the range for use and reset for the next iteration
@@ -810,52 +1387,83 @@ class CompactBlockProcessor internal constructor(
                             backend = backend,
                             downloader = downloader
                         ).collect { enhancingResult ->
-                            Twig.debug { "Enhancing result: $enhancingResult" }
-                            // TODO [#1047]: CompactBlockProcessor: Consider a separate sub-stage result handling
-                            // TODO [#1047]: https://github.com/zcash/zcash-android-wallet-sdk/issues/1047
-                            when (enhancingResult) {
-                                is BlockProcessingResult.UpdateBirthday -> {
-                                    Twig.debug { "Birthday height update reporting" }
+                            Twig.info { "Enhancing result: $enhancingResult" }
+                            resultState = when (enhancingResult) {
+                                is SyncingResult.UpdateBirthday -> {
+                                    Twig.info { "Birthday height update reporting" }
+                                    enhancingResult
                                 }
-                                is BlockProcessingResult.FailedEnhance -> {
+                                is SyncingResult.EnhanceFailed -> {
                                     Twig.error { "Enhancing failed for: $enhancingRange with $enhancingResult" }
+                                    enhancingResult
                                 }
                                 else -> {
-                                    // Transactions enhanced correctly
+                                    // Transactions enhanced correctly. Let's continue with block processing.
+                                    enhancingResult
                                 }
                             }
                             emit(
                                 BatchSyncProgress(
-                                    percentage = PercentDecimal(continuousResult.batch.order / batches.size.toFloat()),
-                                    lastSyncedHeight = getLastScannedHeight(repository),
-                                    result = enhancingResult
+                                    order = continuousResult.batch.order,
+                                    resultState = resultState
                                 )
                             )
                         }
                     }
-
-                    Twig.debug { "All sync stages done for the batch: ${continuousResult.batch}" }
+                    Twig.info {
+                        "All sync stages done for the batch ${continuousResult.batch.order}/${batches.size}:" +
+                            " ${continuousResult.batch} with result state: $resultState"
+                    }
                 }.takeWhile { batchProcessResult ->
-                    batchProcessResult.stageResult == BlockProcessingResult.Success ||
-                        batchProcessResult.stageResult == BlockProcessingResult.UpdateBirthday
+                    batchProcessResult.stageResult == SyncingResult.DeleteSuccess ||
+                        batchProcessResult.stageResult == SyncingResult.UpdateBirthday
                 }.collect()
             }
         }
 
+        /**
+         * Returns count of batches of blocks across all ranges. It works the same when triggered from the Linear
+         * synchronization or from the SbS synchronization.
+         *
+         * @param syncRanges List of ranges of all blocks to process
+         *
+         * @return Count of all batches for processing
+         */
+        private fun getBatchCount(syncRanges: List<ClosedRange<BlockHeight>>): Long {
+            var allRangesBatchCount = 0L
+            var allMissingBlocksCount = 0L
+
+            syncRanges.forEach { range ->
+                val missingBlockCount = range.endInclusive.value - range.start.value + 1
+                val batchCount = (
+                    missingBlockCount / SYNC_BATCH_SIZE +
+                        (if (missingBlockCount.rem(SYNC_BATCH_SIZE) == 0L) 0 else 1)
+                    )
+                allMissingBlocksCount += missingBlockCount
+                allRangesBatchCount += batchCount
+            }
+
+            Twig.debug {
+                "Found $allMissingBlocksCount missing blocks, syncing in $allRangesBatchCount batches of " +
+                    "$SYNC_BATCH_SIZE..."
+            }
+            return allRangesBatchCount
+        }
+
+        /**
+         * Prepare list of all [BlockBatch] internal objects to be processed during a range of
+         * blocks processing
+         *
+         * @param syncRange Current range to be processed
+         * @param network The network we are operating on
+         *
+         * @return List of [BlockBatch] to for synchronization
+         */
         private fun getBatchedBlockList(
             syncRange: ClosedRange<BlockHeight>,
             network: ZcashNetwork
         ): List<BlockBatch> {
-            val missingBlockCount = syncRange.endInclusive.value - syncRange.start.value + 1
-            val batchCount = (
-                missingBlockCount / SYNC_BATCH_SIZE +
-                    (if (missingBlockCount.rem(SYNC_BATCH_SIZE) == 0L) 0 else 1)
-                )
-
-            Twig.debug {
-                "Found $missingBlockCount missing blocks, syncing in $batchCount batches of $SYNC_BATCH_SIZE..."
-            }
-
+            val batchCount = getBatchCount(listOf(syncRange))
             var start = syncRange.start
             return buildList {
                 for (index in 1..batchCount) {
@@ -867,7 +1475,12 @@ class CompactBlockProcessor internal constructor(
                         )
                     ) // subtract 1 on the first value because the range is inclusive
 
-                    add(BlockBatch(index, start..end))
+                    add(
+                        BlockBatch(
+                            order = index,
+                            range = start..end
+                        )
+                    )
                     start = end + 1
                 }
             }
@@ -879,70 +1492,81 @@ class CompactBlockProcessor internal constructor(
          * @param batch the batch of blocks to download.
          */
         @VisibleForTesting
-        @Throws(CompactBlockProcessorException.FailedDownload::class)
-        @Suppress("MagicNumber")
         internal suspend fun downloadBatchOfBlocks(
             downloader: CompactBlockDownloader,
             batch: BlockBatch
-        ): BlockProcessingResult {
+        ): SyncingResult {
             var downloadedBlocks = listOf<JniBlockMeta>()
-            retryUpTo(RETRIES, { CompactBlockProcessorException.FailedDownload(it) }) { failedAttempts ->
+            var downloadException: CompactBlockProcessorException.FailedDownloadException? = null
+
+            retryUpToAndContinue(
+                retries = RETRIES,
+                exceptionWrapper = {
+                    downloadException = CompactBlockProcessorException.FailedDownloadException(it)
+                    downloadException!!
+                }
+            ) { failedAttempts ->
+                @Suppress("MagicNumber")
                 if (failedAttempts == 0) {
                     Twig.verbose { "Starting to download batch $batch" }
                 } else {
                     Twig.warn { "Retrying to download batch $batch after $failedAttempts failure(s)..." }
                 }
-
                 downloadedBlocks = downloader.downloadBlockRange(batch.range)
             }
             Twig.verbose { "Successfully downloaded batch: $batch of $downloadedBlocks blocks" }
 
             return if (downloadedBlocks.isNotEmpty()) {
-                BlockProcessingResult.DownloadSuccess(downloadedBlocks)
+                SyncingResult.DownloadSuccess(downloadedBlocks)
             } else {
-                BlockProcessingResult.FailedDownloadBlocks(batch.range.start)
+                SyncingResult.DownloadFailed(
+                    batch.range.start,
+                    downloadException ?: CompactBlockProcessorException.FailedDownloadException()
+                )
             }
         }
 
         @VisibleForTesting
-        internal suspend fun validateBatchOfBlocks(batch: BlockBatch, backend: TypesafeBackend): BlockProcessingResult {
-            Twig.verbose { "Starting to validate batch $batch" }
-
-            val result = backend.validateCombinedChainOrErrorBlockHeight(batch.range.length())
-
-            return if (null == result) {
-                Twig.verbose { "Successfully validated batch $batch" }
-                BlockProcessingResult.Success
-            } else {
-                BlockProcessingResult.FailedValidateBlocks(result)
-            }
-        }
-
-        @VisibleForTesting
-        internal suspend fun scanBatchOfBlocks(batch: BlockBatch, backend: TypesafeBackend): BlockProcessingResult {
+        internal suspend fun scanBatchOfBlocks(batch: BlockBatch, backend: TypesafeBackend): SyncingResult {
             return runCatching {
-                backend.scanBlocks(batch.range.length())
+                backend.scanBlocks(batch.range.start, batch.range.length())
             }.onSuccess {
                 Twig.verbose { "Successfully scanned batch $batch" }
             }.onFailure {
                 Twig.error { "Failed while scanning batch $batch with $it" }
             }.fold(
-                onSuccess = { BlockProcessingResult.Success },
-                onFailure = { BlockProcessingResult.FailedScanBlocks(batch.range.start) }
+                onSuccess = { SyncingResult.ScanSuccess },
+                onFailure = {
+                    // Check if the error is continuity type
+                    if (it.isScanContinuityError()) {
+                        SyncingResult.ContinuityError(
+                            failedAtHeight = batch.range.start - 1, // To ensure we later rewind below the failed height
+                            exception = CompactBlockProcessorException.FailedScanException(it)
+                        )
+                    } else {
+                        SyncingResult.ScanFailed(
+                            failedAtHeight = batch.range.start,
+                            exception = CompactBlockProcessorException.FailedScanException(it)
+                        )
+                    }
+                }
             )
         }
 
         @VisibleForTesting
         internal suspend fun deleteAllBlockFiles(
             downloader: CompactBlockDownloader,
-            lastKnownHeight: BlockHeight
-        ): BlockProcessingResult {
+            lastKnownHeight: BlockHeight?
+        ): SyncingResult {
             Twig.verbose { "Starting to delete all temporary block files" }
             return if (downloader.compactBlockRepository.deleteAllCompactBlockFiles()) {
                 Twig.verbose { "Successfully deleted all temporary block files" }
-                BlockProcessingResult.Success
+                SyncingResult.DeleteSuccess
             } else {
-                BlockProcessingResult.FailedDeleteBlocks(lastKnownHeight)
+                SyncingResult.DeleteFailed(
+                    lastKnownHeight,
+                    CompactBlockProcessorException.FailedDeleteException()
+                )
             }
         }
 
@@ -950,18 +1574,21 @@ class CompactBlockProcessor internal constructor(
         internal suspend fun deleteFilesOfBatchOfBlocks(
             batch: BlockBatch,
             downloader: CompactBlockDownloader
-        ): BlockProcessingResult {
+        ): SyncingResult {
             Twig.verbose { "Starting to delete temporary block files from batch: $batch" }
 
             return batch.blocks?.let { blocks ->
                 val deleted = downloader.compactBlockRepository.deleteCompactBlockFiles(blocks)
                 if (deleted) {
                     Twig.verbose { "Successfully deleted all temporary batched block files" }
-                    BlockProcessingResult.Success
+                    SyncingResult.DeleteSuccess
                 } else {
-                    BlockProcessingResult.FailedDeleteBlocks(batch.range.start)
+                    SyncingResult.DeleteFailed(
+                        batch.range.start,
+                        CompactBlockProcessorException.FailedDeleteException()
+                    )
                 }
-            } ?: BlockProcessingResult.Success
+            } ?: SyncingResult.DeleteSuccess
         }
 
         @VisibleForTesting
@@ -970,7 +1597,7 @@ class CompactBlockProcessor internal constructor(
             repository: DerivedDataRepository,
             backend: TypesafeBackend,
             downloader: CompactBlockDownloader
-        ): Flow<BlockProcessingResult> = flow {
+        ): Flow<SyncingResult> = flow {
             Twig.debug { "Enhancing transaction details for blocks $range" }
 
             val newTxs = repository.findNewTransactions(range)
@@ -982,13 +1609,13 @@ class CompactBlockProcessor internal constructor(
                 // If the first transaction has been added
                 if (newTxs.size.toLong() == repository.getTransactionCount()) {
                     Twig.debug { "Encountered the first transaction. This changes the birthday height!" }
-                    emit(BlockProcessingResult.UpdateBirthday)
+                    emit(SyncingResult.UpdateBirthday)
                 }
 
                 newTxs.filter { it.minedHeight != null }.onEach { newTransaction ->
                     val trEnhanceResult = enhanceTransaction(newTransaction, backend, downloader)
-                    if (trEnhanceResult is BlockProcessingResult.FailedEnhance) {
-                        Twig.error { "Encountered transaction enhancing error: ${trEnhanceResult.error}" }
+                    if (trEnhanceResult is SyncingResult.EnhanceFailed) {
+                        Twig.error { "Encountered transaction enhancing error: ${trEnhanceResult.exception}" }
                         emit(trEnhanceResult)
                         // We intentionally do not terminate the batch enhancing here, just reporting it
                     }
@@ -996,17 +1623,17 @@ class CompactBlockProcessor internal constructor(
             }
 
             Twig.debug { "Done enhancing transaction details" }
-            emit(BlockProcessingResult.Success)
+            emit(SyncingResult.EnhanceSuccess)
         }
 
         private suspend fun enhanceTransaction(
             transaction: DbTransactionOverview,
             backend: TypesafeBackend,
             downloader: CompactBlockDownloader
-        ): BlockProcessingResult {
+        ): SyncingResult {
             Twig.debug { "Starting enhancing transaction (id:${transaction.id}  block:${transaction.minedHeight})" }
             if (transaction.minedHeight == null) {
-                return BlockProcessingResult.Success
+                return SyncingResult.EnhanceSuccess
             }
 
             return try {
@@ -1031,9 +1658,12 @@ class CompactBlockProcessor internal constructor(
                 )
 
                 Twig.debug { "Done enhancing transaction (id:${transaction.id} block:${transaction.minedHeight})" }
-                BlockProcessingResult.Success
-            } catch (e: CompactBlockProcessorException.EnhanceTransactionError) {
-                BlockProcessingResult.FailedEnhance(e)
+                SyncingResult.EnhanceSuccess
+            } catch (exception: CompactBlockProcessorException.EnhanceTransactionError) {
+                SyncingResult.EnhanceFailed(
+                    transaction.minedHeight,
+                    exception
+                )
             }
         }
 
@@ -1045,7 +1675,7 @@ class CompactBlockProcessor internal constructor(
             downloader: CompactBlockDownloader
         ): ByteArray {
             var transactionDataResult: ByteArray? = null
-            retryUpTo(TRANSACTION_FETCH_RETRIES) { failedAttempts ->
+            retryUpToAndThrow(TRANSACTION_FETCH_RETRIES) { failedAttempts ->
                 if (failedAttempts == 0) {
                     Twig.debug { "Starting to fetch transaction (id:$id, block:$minedHeight)" }
                 } else {
@@ -1086,8 +1716,26 @@ class CompactBlockProcessor internal constructor(
          * @return the last scanned height reported by the repository.
          */
         @VisibleForTesting
-        internal suspend fun getLastScannedHeight(repository: DerivedDataRepository) =
-            repository.lastScannedHeight()
+        internal suspend fun getMaxScannedHeight(backend: TypesafeBackend): GetMaxScannedHeightResult {
+            return runCatching {
+                backend.getMaxScannedHeight()
+            }.onSuccess {
+                Twig.verbose { "Successfully called getMaxScannedHeight with result: $it" }
+            }.onFailure {
+                Twig.error { "Failed to call getMaxScannedHeight with result: $it" }
+            }.fold(
+                onSuccess = {
+                    if (it == null) {
+                        GetMaxScannedHeightResult.None
+                    } else {
+                        GetMaxScannedHeightResult.Success(it)
+                    }
+                },
+                onFailure = {
+                    GetMaxScannedHeightResult.Failure(it)
+                }
+            )
+        }
 
         /**
          * Get the height of the first un-enhanced transaction detail from the repository.
@@ -1143,38 +1791,50 @@ class CompactBlockProcessor internal constructor(
      *
      * @param networkBlockHeight the latest block available to lightwalletd that may or may not be
      * downloaded by this wallet yet.
-     * @param lastSyncedHeight the height up to which the wallet last synced. This determines
-     * where the next sync will begin.
-     * @param lastSyncRange the inclusive range to sync. This represents what we most recently
+     * @param overallSyncRange the inclusive range to sync. This represents what we most recently
      * wanted to sync. In most cases, it will be an invalid range because we'd like to sync blocks
      * that we don't yet have.
      * @param firstUnenhancedHeight the height at which the enhancing should start. Use null if you have no
      * preferences. The height will be calculated automatically for you to continue where it previously ended, or
      * it'll be set to the sync start height in case of the first sync attempt.
      */
-    private fun updateProgress(
+    private fun setProcessorInfo(
         networkBlockHeight: BlockHeight? = _processorInfo.value.networkBlockHeight,
-        lastSyncedHeight: BlockHeight? = _processorInfo.value.lastSyncedHeight,
-        lastSyncRange: ClosedRange<BlockHeight>? = _processorInfo.value.lastSyncRange,
+        overallSyncRange: ClosedRange<BlockHeight>? = _processorInfo.value.overallSyncRange,
         firstUnenhancedHeight: BlockHeight? = _processorInfo.value.firstUnenhancedHeight,
     ) {
         _networkHeight.value = networkBlockHeight
         _processorInfo.value = ProcessorInfo(
             networkBlockHeight = networkBlockHeight,
-            lastSyncedHeight = lastSyncedHeight,
-            lastSyncRange = lastSyncRange,
+            overallSyncRange = overallSyncRange,
             firstUnenhancedHeight = firstUnenhancedHeight
         )
     }
 
-    private suspend fun handleChainError(errorHeight: BlockHeight) {
-        // TODO [#683]: consider an error object containing hash information
-        // TODO [#683]: https://github.com/zcash/zcash-android-wallet-sdk/issues/683
+    /**
+     * Emit an instance of progress.
+     *
+     * @param progress the block syncing progress of type [PercentDecimal] in the range of [0, 1]
+     */
+    private fun setProgress(progress: PercentDecimal = _progress.value) {
+        _progress.value = progress
+    }
+
+    /**
+     * Transmits the given state for this processor.
+     */
+    private suspend fun setState(newState: State) {
+        _state.value = newState
+    }
+
+    private suspend fun handleChainError(errorHeight: BlockHeight?) {
         printValidationErrorInfo(errorHeight)
-        determineLowerBound(errorHeight).let { lowerBound ->
-            Twig.debug { "handling chain error at $errorHeight by rewinding to block $lowerBound" }
-            onChainErrorListener?.invoke(errorHeight, lowerBound)
-            rewindToNearestHeight(lowerBound, true)
+        errorHeight?.let {
+            determineLowerBound(errorHeight).let { lowerBound ->
+                Twig.debug { "Handling chain error at $errorHeight by rewinding to block $lowerBound" }
+                onChainErrorListener?.invoke(errorHeight, lowerBound)
+                rewindToNearestHeight(lowerBound)
+            }
         }
     }
 
@@ -1196,145 +1856,84 @@ class CompactBlockProcessor internal constructor(
     /**
      * Rewind back at least two weeks worth of blocks.
      */
-    suspend fun quickRewind() {
-        val height = max(_processorInfo.value.lastSyncedHeight, repository.lastScannedHeight())
+    suspend fun quickRewind(): Boolean {
+        val height = when (val result = getMaxScannedHeight(backend)) {
+            is GetMaxScannedHeightResult.Success -> result.height
+            else -> return false
+        }
         val blocksPer14Days = 14.days.inWholeMilliseconds / ZcashSdk.BLOCK_INTERVAL_MILLIS.toInt()
         val twoWeeksBack = BlockHeight.new(
             network,
             (height.value - blocksPer14Days).coerceAtLeast(lowerBoundHeight.value)
         )
-        rewindToNearestHeight(twoWeeksBack, false)
+        return rewindToNearestHeight(twoWeeksBack)
     }
 
-    /**
-     * @param alsoClearBlockCache when true, also clear the block cache which forces a redownload of
-     * blocks. Otherwise, the cached blocks will be used in the rescan, which in most cases, is fine.
-     */
     @Suppress("LongMethod")
-    suspend fun rewindToNearestHeight(
-        height: BlockHeight,
-        alsoClearBlockCache: Boolean = false
-    ) {
+    suspend fun rewindToNearestHeight(height: BlockHeight): Boolean {
         processingMutex.withLockLogged("rewindToHeight") {
-            val lastSyncedHeight = _processorInfo.value.lastSyncedHeight
-            val lastLocalBlock = repository.lastScannedHeight()
+            val lastLocalBlock = when (val result = getMaxScannedHeight(backend)) {
+                is GetMaxScannedHeightResult.Success -> result.height
+                else -> return false
+            }
             val targetHeight = getNearestRewindHeight(height)
 
             Twig.debug {
-                "Rewinding from $lastSyncedHeight to requested height: $height using target height: " +
-                    "$targetHeight with last local block: $lastLocalBlock"
+                "Rewinding to requested height: $height using target height: $targetHeight with last local block:" +
+                    " $lastLocalBlock"
             }
 
-            if (null == lastSyncedHeight && targetHeight < lastLocalBlock) {
+            if (targetHeight < lastLocalBlock) {
                 Twig.debug { "Rewinding because targetHeight is less than lastLocalBlock." }
                 runCatching {
                     backend.rewindToHeight(targetHeight)
+                    downloader.rewindToHeight(targetHeight)
                 }.onFailure {
                     Twig.error { "Rewinding to the targetHeight $targetHeight failed with $it" }
-                }
-            } else if (null != lastSyncedHeight && targetHeight < lastSyncedHeight) {
-                Twig.debug { "Rewinding because targetHeight is less than lastSyncedHeight." }
-                runCatching {
-                    backend.rewindToHeight(targetHeight)
-                }.onFailure {
-                    Twig.error { "Rewinding to the targetHeight $targetHeight failed with $it" }
+                }.onSuccess {
+                    Twig.info { "Rewind to $targetHeight was successful." }
+                    setState(newState = State.Syncing)
+                    setProgress(progress = PercentDecimal.ZERO_PERCENT)
+                    setProcessorInfo(overallSyncRange = null)
                 }
             } else {
-                Twig.debug {
-                    "Not rewinding dataDb because the last synced height is $lastSyncedHeight and the" +
-                        " last local block is $lastLocalBlock both of which are less than the target height of " +
-                        "$targetHeight"
-                }
-            }
-
-            val currentNetworkBlockHeight = _processorInfo.value.networkBlockHeight
-
-            if (alsoClearBlockCache) {
-                Twig.debug {
-                    "Also clearing block cache back to $targetHeight. These rewound blocks will download " +
-                        "in the next scheduled scan"
-                }
-                downloader.rewindToHeight(targetHeight)
-                // communicate that the wallet is no longer synced because it might remain this way for 20+ second
-                // because we only download on 20s time boundaries so we can't trigger any immediate action
-                setState(State.Syncing)
-                if (null == currentNetworkBlockHeight) {
-                    updateProgress(
-                        lastSyncedHeight = targetHeight,
-                        lastSyncRange = null
-                    )
-                } else {
-                    updateProgress(
-                        lastSyncedHeight = targetHeight,
-                        lastSyncRange = (targetHeight + 1)..currentNetworkBlockHeight
-                    )
-                }
-                _progress.value = PercentDecimal.ZERO_PERCENT
-            } else {
-                if (null == currentNetworkBlockHeight) {
-                    updateProgress(
-                        lastSyncedHeight = targetHeight,
-                        lastSyncRange = null
-                    )
-                } else {
-                    updateProgress(
-                        lastSyncedHeight = targetHeight,
-                        lastSyncRange = (targetHeight + 1)..currentNetworkBlockHeight
-                    )
-                }
-
-                _progress.value = PercentDecimal.ZERO_PERCENT
-
-                if (null != lastSyncedHeight) {
-                    val range = (targetHeight + 1)..lastSyncedHeight
-                    Twig.debug {
-                        "We kept the cache blocks in place so we don't need to wait for the next " +
-                            "scheduled download to rescan. Instead we will rescan and validate blocks " +
-                            "${range.start}..${range.endInclusive}"
-                    }
-
-                    syncBlocksAndEnhanceTransactions(
-                        syncRange = range,
-                        withDownload = false,
-                        enhanceStartHeight = null
-                    )
+                Twig.info {
+                    "Not rewinding dataDb because last local block is $lastLocalBlock which is less than the target " +
+                        "height of $targetHeight"
                 }
             }
         }
+        return true
     }
 
     /** insightful function for debugging these critical errors */
-    private suspend fun printValidationErrorInfo(errorHeight: BlockHeight, count: Int = 11) {
+    private suspend fun printValidationErrorInfo(errorHeight: BlockHeight?, count: Int = 11) {
         // Note: blocks are public information so it's okay to print them but, still, let's not unless we're
         // debugging something
         if (!BuildConfig.DEBUG) {
             return
         }
 
-        var errorInfo = fetchValidationErrorInfo(errorHeight)
-        Twig.debug { "validation failed at block ${errorInfo.errorHeight} with hash: ${errorInfo.hash}" }
+        if (errorHeight == null) {
+            Twig.debug { "Validation failed at unspecified block height" }
+            return
+        }
 
-        errorInfo = fetchValidationErrorInfo(errorHeight + 1)
-        Twig.debug { "the next block is ${errorInfo.errorHeight} with hash: ${errorInfo.hash}" }
+        var errorInfo = ValidationErrorInfo(errorHeight)
+        Twig.debug { "Validation failed at block ${errorInfo.errorHeight}" }
+
+        errorInfo = ValidationErrorInfo(errorHeight + 1)
+        Twig.debug { "The next block is ${errorInfo.errorHeight}" }
 
         Twig.debug { "=================== BLOCKS [$errorHeight..${errorHeight.value + count - 1}]: START ========" }
         repeat(count) { i ->
             val height = errorHeight + i
             val block = downloader.compactBlockRepository.findCompactBlock(height)
-            // sometimes the initial block was inserted via checkpoint and will not appear in the cache. We can get
-            // the hash another way.
-            val checkedHash = block?.hash ?: repository.findBlockHash(height)
-            Twig.debug { "block: $height\thash=${checkedHash?.toHexReversed()}" }
+            Twig.debug { "block: $height\thash=${block?.hash?.toHexReversed()}" }
         }
         Twig.debug { "=================== BLOCKS [$errorHeight..${errorHeight.value + count - 1}]: END ========" }
     }
 
-    private suspend fun fetchValidationErrorInfo(errorHeight: BlockHeight): ValidationErrorInfo {
-        val hash = repository.findBlockHash(errorHeight + 1)?.toHexReversed()
-
-        return ValidationErrorInfo(errorHeight, hash)
-    }
-
     /**
      * Called for every noteworthy error.
      *
@@ -1395,31 +1994,26 @@ class CompactBlockProcessor internal constructor(
      * @param account the account to check for balance info.
      *
      * @return an instance of WalletBalance containing information about available and total funds.
+     *
+     * @throws RustLayerException.BalanceException if any error occurs while getting the balances via the Rust layer
      */
     suspend fun getBalanceInfo(account: Account): WalletBalance {
-        @Suppress("TooGenericExceptionCaught")
-        return try {
+        return runCatching {
             val balanceTotal = backend.getBalance(account)
-            Twig.debug { "found total balance: $balanceTotal" }
+            Twig.info { "Found total balance: $balanceTotal" }
             val balanceAvailable = backend.getVerifiedBalance(account)
-            Twig.debug { "found available balance: $balanceAvailable" }
+            Twig.info { "Found available balance: $balanceAvailable" }
             WalletBalance(balanceTotal, balanceAvailable)
-        } catch (t: Throwable) {
-            Twig.debug { "failed to get balance due to $t" }
-            throw RustLayerException.BalanceException(t)
+        }.onFailure {
+            Twig.error(it) { "Failed to get balance due to ${it.localizedMessage}" }
+        }.getOrElse {
+            throw RustLayerException.BalanceException(it)
         }
     }
 
     suspend fun getUtxoCacheBalance(address: String): WalletBalance =
         backend.getDownloadedUtxoBalance(address)
 
-    /**
-     * Transmits the given state for this processor.
-     */
-    private suspend fun setState(newState: State) {
-        _state.value = newState
-    }
-
     /**
      * Sealed class representing the various states of this processor.
      */
@@ -1442,11 +2036,9 @@ class CompactBlockProcessor internal constructor(
          * block height available from the server is greater than what we have locally. We move out
          * of this state once our local height matches the server.
          *
-         * **Validating** is when the blocks that have been downloaded are actively being validated to
-         * ensure that there are no gaps and that every block is chain-sequential to the previous
-         * block, which determines whether a reorg has happened on our watch.
-         *
-         * **Scanning** is when the blocks that have been downloaded are actively being decrypted.
+         * **Scanning** is when the blocks that have been downloaded are actively being decrypted and validated to
+         * ensure that there are no gaps and that every block is chain-sequential to the previous block, which
+         * determines whether a reorg has happened on our watch.
          *
          * **Deleting** is when the temporary block files being removed from the persistence.
          *
@@ -1460,7 +2052,7 @@ class CompactBlockProcessor internal constructor(
 
         /**
          * [State] for when we are done with syncing the blocks, for now, i.e. all necessary stages done (download,
-         * validate, and scan).
+         * scan).
          */
         class Synced(val syncedRange: ClosedRange<BlockHeight>?) : IConnected, ISyncing, State()
 
@@ -1481,31 +2073,12 @@ class CompactBlockProcessor internal constructor(
         object Initialized : State()
     }
 
-    /**
-     * Progress model class for sharing the whole batch sync progress out of the sync process.
-     */
-    internal data class BatchSyncProgress(
-        val percentage: PercentDecimal,
-        val lastSyncedHeight: BlockHeight?,
-        val result: BlockProcessingResult
-    )
-
-    /**
-     * Progress model class for sharing particular sync stage result internally in the sync process.
-     */
-    private data class SyncStageResult(
-        val batch: BlockBatch,
-        val stageResult: BlockProcessingResult
-    )
-
     /**
      * Data class for holding detailed information about the processor.
      *
      * @param networkBlockHeight the latest block available to lightwalletd that may or may not be
      * downloaded by this wallet yet.
-     * @param lastSyncedHeight the height up to which the wallet last synced. This determines
-     * where the next sync will begin.
-     * @param lastSyncRange inclusive range to sync. Meaning, if the range is 10..10,
+     * @param overallSyncRange inclusive range to sync. Meaning, if the range is 10..10,
      * then we will download exactly block 10. If the range is 11..10, then we want to download
      * block 11 but can't.
      * @param firstUnenhancedHeight the height in which the enhancing should start, or null in case of no previous
@@ -1513,47 +2086,12 @@ class CompactBlockProcessor internal constructor(
      */
     data class ProcessorInfo(
         val networkBlockHeight: BlockHeight?,
-        val lastSyncedHeight: BlockHeight?,
-        val lastSyncRange: ClosedRange<BlockHeight>?,
+        val overallSyncRange: ClosedRange<BlockHeight>?,
         val firstUnenhancedHeight: BlockHeight?
-    ) {
-        /**
-         * Determines whether this instance is actively syncing compact blocks.
-         *
-         * @return true when there are more than zero blocks remaining to sync.
-         */
-        val isSyncing: Boolean
-            get() =
-                lastSyncedHeight != null &&
-                    lastSyncRange != null &&
-                    !lastSyncRange.isEmpty() &&
-                    lastSyncedHeight < lastSyncRange.endInclusive
-
-        /**
-         * The amount of sync progress from 0 to 100.
-         */
-        @Suppress("MagicNumber")
-        val syncProgress
-            get() = when {
-                lastSyncedHeight == null -> 0
-                lastSyncRange == null -> 100
-                lastSyncedHeight >= lastSyncRange.endInclusive -> 100
-                else -> {
-                    // when lastSyncedHeight == lastSyncedRange.first, we have synced one block, thus the offsets
-                    val blocksSynced =
-                        (lastSyncedHeight.value - lastSyncRange.start.value + 1).coerceAtLeast(0)
-                    // we sync the range inclusively so 100..100 is one block to sync, thus the offset
-                    val numberOfBlocks =
-                        lastSyncRange.endInclusive.value - lastSyncRange.start.value + 1
-                    // take the percentage then convert and round
-                    ((blocksSynced.toFloat() / numberOfBlocks) * 100.0f).coerceAtMost(100.0f).roundToInt()
-                }
-            }
-    }
+    )
 
     data class ValidationErrorInfo(
-        val errorHeight: BlockHeight,
-        val hash: String?
+        val errorHeight: BlockHeight
     )
 
     //
@@ -1584,11 +2122,3 @@ private fun LightWalletEndpointInfoUnsafe.matchingNetwork(network: String): Bool
     }
     return chainName.toId() == network.toId()
 }
-
-private fun max(a: BlockHeight?, b: BlockHeight) = if (null == a) {
-    b
-} else if (a.value > b.value) {
-    a
-} else {
-    b
-}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/BatchSyncProgress.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/BatchSyncProgress.kt
new file mode 100644
index 00000000..293a0184
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/BatchSyncProgress.kt
@@ -0,0 +1,10 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+/**
+ * Progress model class for sharing the whole batch synchronization progress out of the synchronization process.
+ */
+internal data class BatchSyncProgress(
+    val order: Long = 0,
+    val resultState: SyncingResult =
+        SyncingResult.AllSuccess
+)
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetMaxScannedHeightResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetMaxScannedHeightResult.kt
new file mode 100644
index 00000000..2eba89b3
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetMaxScannedHeightResult.kt
@@ -0,0 +1,12 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.model.BlockHeight
+
+/**
+ * Internal class for sharing get max scanned height action result.
+ */
+internal sealed class GetMaxScannedHeightResult {
+    data class Success(val height: BlockHeight) : GetMaxScannedHeightResult()
+    data object None : GetMaxScannedHeightResult()
+    data class Failure(val exception: Throwable) : GetMaxScannedHeightResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetScanProgressResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetScanProgressResult.kt
new file mode 100644
index 00000000..a3cb9449
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetScanProgressResult.kt
@@ -0,0 +1,16 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.internal.model.ScanProgress
+import cash.z.ecc.android.sdk.model.PercentDecimal
+
+/**
+ * Internal class for sharing get scan progress action result.
+ */
+internal sealed class GetScanProgressResult {
+    data class Success(val scanProgress: ScanProgress) : GetScanProgressResult() {
+        fun toPercentDecimal() = PercentDecimal(scanProgress.getSafeRation())
+    }
+
+    data object None : GetScanProgressResult()
+    data class Failure(val exception: Throwable) : GetScanProgressResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetSubtreeRootsResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetSubtreeRootsResult.kt
new file mode 100644
index 00000000..a87d2ceb
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/GetSubtreeRootsResult.kt
@@ -0,0 +1,13 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.internal.model.SubtreeRoot
+
+/**
+ * Internal class for get subtree roots action result.
+ */
+internal sealed class GetSubtreeRootsResult {
+    data class SpendBeforeSync(val subTreeRootList: List<SubtreeRoot>) : GetSubtreeRootsResult()
+    data object Linear : GetSubtreeRootsResult()
+    data object FailureConnection : GetSubtreeRootsResult()
+    data class OtherFailure(val exception: Throwable) : GetSubtreeRootsResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/PutSaplingSubtreeRootsResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/PutSaplingSubtreeRootsResult.kt
new file mode 100644
index 00000000..d72c4ce6
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/PutSaplingSubtreeRootsResult.kt
@@ -0,0 +1,11 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.model.BlockHeight
+
+/**
+ * Internal class for sharing put sapling subtree roots action result.
+ */
+internal sealed class PutSaplingSubtreeRootsResult {
+    object Success : PutSaplingSubtreeRootsResult()
+    data class Failure(val failedAtHeight: BlockHeight, val exception: Throwable) : PutSaplingSubtreeRootsResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SbSPreparationResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SbSPreparationResult.kt
new file mode 100644
index 00000000..c4613394
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SbSPreparationResult.kt
@@ -0,0 +1,26 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
+import cash.z.ecc.android.sdk.model.BlockHeight
+
+/**
+ * Internal class for sharing pre-synchronization steps result.
+ */
+internal sealed class SbSPreparationResult {
+    object ConnectionFailure : SbSPreparationResult()
+    data class ProcessFailure(
+        val failedAtHeight: BlockHeight,
+        val exception: Throwable
+    ) : SbSPreparationResult() {
+        fun toBlockProcessingResult(): CompactBlockProcessor.BlockProcessingResult =
+            CompactBlockProcessor.BlockProcessingResult.SyncFailure(
+                this.failedAtHeight,
+                this.exception
+            )
+    }
+    data class Success(
+        val suggestedRangesResult: SuggestScanRangesResult,
+        val verifyRangeResult: VerifySuggestedScanRange
+    ) : SbSPreparationResult()
+    object NoMoreBlocksToProcess : SbSPreparationResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SuggestScanRangesResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SuggestScanRangesResult.kt
new file mode 100644
index 00000000..2b886365
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SuggestScanRangesResult.kt
@@ -0,0 +1,12 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.internal.model.ScanRange
+import cash.z.ecc.android.sdk.model.BlockHeight
+
+/**
+ * Internal class for sharing suggested scan ranges action result.
+ */
+internal sealed class SuggestScanRangesResult {
+    data class Success(val ranges: List<ScanRange>) : SuggestScanRangesResult()
+    data class Failure(val failedAtHeight: BlockHeight, val exception: Throwable) : SuggestScanRangesResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SyncStageResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SyncStageResult.kt
new file mode 100644
index 00000000..9195254c
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SyncStageResult.kt
@@ -0,0 +1,11 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.internal.model.BlockBatch
+
+/**
+ * Common progress model class for sharing a batch synchronization stage result internally in the synchronization loop.
+ */
+internal data class SyncStageResult(
+    val batch: BlockBatch,
+    val stageResult: SyncingResult
+)
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SyncingResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SyncingResult.kt
new file mode 100644
index 00000000..be8046ae
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/SyncingResult.kt
@@ -0,0 +1,52 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.block.processor.CompactBlockProcessor
+import cash.z.ecc.android.sdk.exception.CompactBlockProcessorException
+import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.model.BlockHeight
+
+/**
+ * Internal class for the overall synchronization process result reporting.
+ */
+internal sealed class SyncingResult {
+    override fun toString(): String = this::class.java.simpleName
+
+    object AllSuccess : SyncingResult()
+    object RestartSynchronization : SyncingResult()
+    data class DownloadSuccess(val downloadedBlocks: List<JniBlockMeta>?) : SyncingResult() {
+        override fun toString() = "${this::class.java.simpleName} with ${downloadedBlocks?.size ?: "none"} blocks"
+    }
+    interface Failure {
+        val failedAtHeight: BlockHeight?
+        val exception: CompactBlockProcessorException
+        fun toBlockProcessingResult(): CompactBlockProcessor.BlockProcessingResult =
+            CompactBlockProcessor.BlockProcessingResult.SyncFailure(
+                this.failedAtHeight,
+                this.exception
+            )
+    }
+    data class DownloadFailed(
+        override val failedAtHeight: BlockHeight,
+        override val exception: CompactBlockProcessorException
+    ) : Failure, SyncingResult()
+    object ScanSuccess : SyncingResult()
+    data class ScanFailed(
+        override val failedAtHeight: BlockHeight,
+        override val exception: CompactBlockProcessorException
+    ) : Failure, SyncingResult()
+    object DeleteSuccess : SyncingResult()
+    data class DeleteFailed(
+        override val failedAtHeight: BlockHeight?,
+        override val exception: CompactBlockProcessorException
+    ) : Failure, SyncingResult()
+    object EnhanceSuccess : SyncingResult()
+    data class EnhanceFailed(
+        override val failedAtHeight: BlockHeight,
+        override val exception: CompactBlockProcessorException
+    ) : Failure, SyncingResult()
+    object UpdateBirthday : SyncingResult()
+    data class ContinuityError(
+        override val failedAtHeight: BlockHeight,
+        override val exception: CompactBlockProcessorException
+    ) : Failure, SyncingResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/UpdateChainTipResult.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/UpdateChainTipResult.kt
new file mode 100644
index 00000000..53d218f5
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/UpdateChainTipResult.kt
@@ -0,0 +1,11 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.model.BlockHeight
+
+/**
+ * Internal class for sharing update chain tip action result.
+ */
+internal sealed class UpdateChainTipResult {
+    data class Success(val height: BlockHeight) : UpdateChainTipResult()
+    data class Failure(val failedAtHeight: BlockHeight, val exception: Throwable) : UpdateChainTipResult()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/VerifySuggestedScanRange.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/VerifySuggestedScanRange.kt
new file mode 100644
index 00000000..90ed3824
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/block/processor/model/VerifySuggestedScanRange.kt
@@ -0,0 +1,11 @@
+package cash.z.ecc.android.sdk.block.processor.model
+
+import cash.z.ecc.android.sdk.internal.model.ScanRange
+
+/**
+ * Internal class for sharing verify suggested scan range action result.
+ */
+internal sealed class VerifySuggestedScanRange {
+    data class ShouldVerify(val scanRange: ScanRange) : VerifySuggestedScanRange()
+    object NoRangeToVerify : VerifySuggestedScanRange()
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/exception/Exceptions.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/exception/Exceptions.kt
index b248f41d..2630a669 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/exception/Exceptions.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/exception/Exceptions.kt
@@ -3,6 +3,7 @@ package cash.z.ecc.android.sdk.exception
 import cash.z.ecc.android.sdk.internal.SaplingParameters
 import cash.z.ecc.android.sdk.internal.model.Checkpoint
 import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.FirstClassByteArray
 import cash.z.ecc.android.sdk.model.ZcashNetwork
 import co.electriccoin.lightwallet.client.model.BlockHeightUnsafe
 
@@ -79,22 +80,32 @@ sealed class CompactBlockProcessorException(message: String, cause: Throwable? =
         null
     )
     class FailedReorgRepair(message: String) : CompactBlockProcessorException(message)
-    class FailedDownload(cause: Throwable? = null) : CompactBlockProcessorException(
-        "Error while downloading blocks. This most " +
-            "likely means the server is down or slow to respond. See logs for details.",
-        cause
-    )
-    class Disconnected(cause: Throwable? = null) :
-        CompactBlockProcessorException("Disconnected Error. Unable to download blocks due to ${cause?.message}", cause)
-    object Uninitialized : CompactBlockProcessorException(
+    class Uninitialized(cause: Throwable? = null) : CompactBlockProcessorException(
         "Cannot process blocks because the wallet has not been" +
             " initialized. Verify that the seed phrase was properly created or imported. If so, then this problem" +
-            " can be fixed by re-importing the wallet."
+            " can be fixed by re-importing the wallet.",
+        cause
     )
     object NoAccount : CompactBlockProcessorException(
         "Attempting to scan without an account. This is probably a setup error or a race condition."
     )
 
+    class FailedDownloadException(cause: Throwable? = null) : CompactBlockProcessorException(
+        "Error while downloading blocks. This most likely means the server is down or slow to respond. " +
+            "See logs for details.",
+        cause
+    )
+    class FailedScanException(cause: Throwable? = null) : CompactBlockProcessorException(
+        "Error while scanning blocks. This most likely means a problem with locally persisted data. " +
+            "See logs for details.",
+        cause
+    )
+    class FailedDeleteException(cause: Throwable? = null) : CompactBlockProcessorException(
+        "Error while deleting block files. This most likely means the data are not persisted correctly." +
+            " See logs for details.",
+        cause
+    )
+
     open class EnhanceTransactionError(
         message: String,
         val height: BlockHeight,
@@ -240,10 +251,20 @@ sealed class LightWalletException(message: String, cause: Throwable? = null) : S
         cause
     )
 
+    class GetSubtreeRootsException(code: Int, description: String?, cause: Throwable) : SdkException(
+        "Failed to get subtree roots with code: $code due to: ${description ?: "-"}",
+        cause
+    )
+
     class FetchUtxosException(code: Int, description: String?, cause: Throwable) : SdkException(
         "Failed to fetch UTXOs with code: $code due to: ${description ?: "-"}",
         cause
     )
+
+    class GetLatestBlockHeightException(code: Int, description: String?, cause: Throwable) : SdkException(
+        "Failed to fetch latest block height with code: $code due to: ${description ?: "-"}",
+        cause
+    )
 }
 
 /**
@@ -264,7 +285,7 @@ sealed class TransactionEncoderException(
     object MissingParamsException : TransactionEncoderException(
         "Cannot send funds due to missing spend or output params and attempting to download them failed."
     )
-    class TransactionNotFoundException(transactionId: Long) : TransactionEncoderException(
+    class TransactionNotFoundException(transactionId: FirstClassByteArray) : TransactionEncoderException(
         "Unable to find transactionId $transactionId in the repository. This means the wallet created a transaction " +
             "and then returned a row ID that does not actually exist. This is a scenario where the wallet should " +
             "have thrown an exception but failed to do so."
@@ -274,7 +295,7 @@ sealed class TransactionEncoderException(
             " with id $transactionId, does not have any raw data. This is a scenario where the wallet should have " +
             "thrown an exception but failed to do so."
     )
-    class IncompleteScanException(lastScannedHeight: BlockHeight) : TransactionEncoderException(
+    class IncompleteScanException(lastScannedHeight: BlockHeight?) : TransactionEncoderException(
         "Cannot" +
             " create spending transaction because scanning is incomplete. We must scan up to the" +
             " latest height to know which consensus rules to apply. However, the last scanned" +
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackend.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackend.kt
index 97274eda..23c19f1c 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackend.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackend.kt
@@ -1,32 +1,28 @@
 package cash.z.ecc.android.sdk.internal
 
-import cash.z.ecc.android.sdk.internal.model.Checkpoint
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.internal.model.ScanProgress
+import cash.z.ecc.android.sdk.internal.model.ScanRange
+import cash.z.ecc.android.sdk.internal.model.SubtreeRoot
+import cash.z.ecc.android.sdk.internal.model.TreeState
 import cash.z.ecc.android.sdk.model.Account
 import cash.z.ecc.android.sdk.model.BlockHeight
-import cash.z.ecc.android.sdk.model.UnifiedFullViewingKey
+import cash.z.ecc.android.sdk.model.FirstClassByteArray
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.WalletBalance
 import cash.z.ecc.android.sdk.model.Zatoshi
 import cash.z.ecc.android.sdk.model.ZcashNetwork
-import java.lang.RuntimeException
-import kotlin.jvm.Throws
 
 @Suppress("TooManyFunctions")
 internal interface TypesafeBackend {
 
     val network: ZcashNetwork
 
-    suspend fun initAccountsTable(vararg keys: UnifiedFullViewingKey)
-
-    suspend fun initAccountsTable(
+    suspend fun createAccountAndGetSpendingKey(
         seed: ByteArray,
-        numberOfAccounts: Int
-    ): List<UnifiedFullViewingKey>
-
-    suspend fun initBlocksTable(checkpoint: Checkpoint)
-
-    suspend fun createAccountAndGetSpendingKey(seed: ByteArray): UnifiedSpendingKey
+        treeState: TreeState,
+        recoverUntil: BlockHeight?
+    ): UnifiedSpendingKey
 
     @Suppress("LongParameterList")
     suspend fun createToAddress(
@@ -34,12 +30,12 @@ internal interface TypesafeBackend {
         to: String,
         value: Long,
         memo: ByteArray? = byteArrayOf()
-    ): Long
+    ): FirstClassByteArray
 
     suspend fun shieldToAddress(
         usk: UnifiedSpendingKey,
         memo: ByteArray? = byteArrayOf()
-    ): Long
+    ): FirstClassByteArray
 
     suspend fun getCurrentAddress(account: Account): String
 
@@ -55,18 +51,12 @@ internal interface TypesafeBackend {
 
     suspend fun rewindToHeight(height: BlockHeight)
 
-    suspend fun getLatestBlockHeight(): BlockHeight?
+    suspend fun getLatestCacheHeight(): BlockHeight?
 
     suspend fun findBlockMetadata(height: BlockHeight): JniBlockMeta?
 
     suspend fun rewindBlockMetadataToHeight(height: BlockHeight)
 
-    /**
-     * @param limit The limit provides an efficient way how to restrict the portion of blocks, which will be validated.
-     * @return Null if successful. If an error occurs, the height will be the height where the error was detected.
-     */
-    suspend fun validateCombinedChainOrErrorBlockHeight(limit: Long?): BlockHeight?
-
     suspend fun getDownloadedUtxoBalance(address: String): WalletBalance
 
     @Suppress("LongParameterList")
@@ -79,9 +69,7 @@ internal interface TypesafeBackend {
         height: BlockHeight
     )
 
-    suspend fun getSentMemoAsUtf8(idNote: Long): String?
-
-    suspend fun getReceivedMemoAsUtf8(idNote: Long): String?
+    suspend fun getMemoAsUtf8(txId: ByteArray, outputIndex: Int): String?
 
     suspend fun initDataDb(seed: ByteArray?): Int
 
@@ -89,7 +77,57 @@ internal interface TypesafeBackend {
      * @throws RuntimeException as a common indicator of the operation failure
      */
     @Throws(RuntimeException::class)
-    suspend fun scanBlocks(limit: Long?)
+    suspend fun putSaplingSubtreeRoots(
+        startIndex: Long,
+        roots: List<SubtreeRoot>,
+    )
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun updateChainTip(height: BlockHeight)
+
+    /**
+     * Returns the height to which the wallet has been fully scanned.
+     *
+     * This is the height for which the wallet has fully trial-decrypted this and all
+     * preceding blocks above the wallet's birthday height.
+     *
+     * @return The height to which the wallet has been fully scanned, or Null if no blocks have been scanned.
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    suspend fun getFullyScannedHeight(): BlockHeight?
+
+    /**
+     * Returns the maximum height that the wallet has scanned.
+     *
+     * If the wallet is fully synced, this will be equivalent to `getFullyScannedHeight`;
+     * otherwise the maximal scanned height is likely to be greater than the fully scanned
+     * height due to the fact that out-of-order scanning can leave gaps.
+     *
+     * @return The maximum height that the wallet has scanned, or Null if no blocks have been scanned.
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    suspend fun getMaxScannedHeight(): BlockHeight?
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun scanBlocks(fromHeight: BlockHeight, limit: Long)
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun getScanProgress(): ScanProgress?
+
+    /**
+     * @throws RuntimeException as a common indicator of the operation failure
+     */
+    @Throws(RuntimeException::class)
+    suspend fun suggestScanRanges(): List<ScanRange>
 
     suspend fun decryptAndStoreTransaction(tx: ByteArray)
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackendImpl.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackendImpl.kt
index c4c572c1..41801599 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackendImpl.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/TypesafeBackendImpl.kt
@@ -1,15 +1,18 @@
 package cash.z.ecc.android.sdk.internal
 
-import cash.z.ecc.android.sdk.internal.model.Checkpoint
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
+import cash.z.ecc.android.sdk.internal.model.JniSubtreeRoot
+import cash.z.ecc.android.sdk.internal.model.ScanProgress
+import cash.z.ecc.android.sdk.internal.model.ScanRange
+import cash.z.ecc.android.sdk.internal.model.SubtreeRoot
+import cash.z.ecc.android.sdk.internal.model.TreeState
 import cash.z.ecc.android.sdk.model.Account
 import cash.z.ecc.android.sdk.model.BlockHeight
-import cash.z.ecc.android.sdk.model.UnifiedFullViewingKey
+import cash.z.ecc.android.sdk.model.FirstClassByteArray
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.WalletBalance
 import cash.z.ecc.android.sdk.model.Zatoshi
 import cash.z.ecc.android.sdk.model.ZcashNetwork
-import cash.z.ecc.android.sdk.tool.DerivationTool
 import kotlinx.coroutines.withContext
 
 @Suppress("TooManyFunctions")
@@ -18,53 +21,45 @@ internal class TypesafeBackendImpl(private val backend: Backend) : TypesafeBacke
     override val network: ZcashNetwork
         get() = ZcashNetwork.from(backend.networkId)
 
-    override suspend fun initAccountsTable(vararg keys: UnifiedFullViewingKey) {
-        val ufvks = Array(keys.size) { keys[it].encoding }
-        @Suppress("SpreadOperator")
-        backend.initAccountsTable(*ufvks)
-    }
-
-    override suspend fun initAccountsTable(
+    override suspend fun createAccountAndGetSpendingKey(
         seed: ByteArray,
-        numberOfAccounts: Int
-    ): List<UnifiedFullViewingKey> {
-        return DerivationTool.getInstance().deriveUnifiedFullViewingKeys(seed, network, numberOfAccounts)
-    }
-
-    override suspend fun initBlocksTable(checkpoint: Checkpoint) {
-        backend.initBlocksTable(
-            checkpoint.height.value,
-            checkpoint.hash,
-            checkpoint.epochSeconds,
-            checkpoint.tree
+        treeState: TreeState,
+        recoverUntil: BlockHeight?
+    ): UnifiedSpendingKey {
+        return UnifiedSpendingKey(
+            backend.createAccount(
+                seed = seed,
+                treeState = treeState.encoded,
+                recoverUntil = recoverUntil?.value
+            )
         )
     }
 
-    override suspend fun createAccountAndGetSpendingKey(seed: ByteArray): UnifiedSpendingKey {
-        return UnifiedSpendingKey(backend.createAccount(seed))
-    }
-
     @Suppress("LongParameterList")
     override suspend fun createToAddress(
         usk: UnifiedSpendingKey,
         to: String,
         value: Long,
         memo: ByteArray?
-    ): Long = backend.createToAddress(
-        usk.account.value,
-        usk.copyBytes(),
-        to,
-        value,
-        memo
+    ): FirstClassByteArray = FirstClassByteArray(
+        backend.createToAddress(
+            usk.account.value,
+            usk.copyBytes(),
+            to,
+            value,
+            memo
+        )
     )
 
     override suspend fun shieldToAddress(
         usk: UnifiedSpendingKey,
         memo: ByteArray?
-    ): Long = backend.shieldToAddress(
-        usk.account.value,
-        usk.copyBytes(),
-        memo
+    ): FirstClassByteArray = FirstClassByteArray(
+        backend.shieldToAddress(
+            usk.account.value,
+            usk.copyBytes(),
+            memo
+        )
     )
 
     override suspend fun getCurrentAddress(account: Account): String {
@@ -98,8 +93,8 @@ internal class TypesafeBackendImpl(private val backend: Backend) : TypesafeBacke
         backend.rewindToHeight(height.value)
     }
 
-    override suspend fun getLatestBlockHeight(): BlockHeight? {
-        return backend.getLatestHeight()?.let {
+    override suspend fun getLatestCacheHeight(): BlockHeight? {
+        return backend.getLatestCacheHeight()?.let {
             BlockHeight.new(
                 ZcashNetwork.from(backend.networkId),
                 it
@@ -115,19 +110,6 @@ internal class TypesafeBackendImpl(private val backend: Backend) : TypesafeBacke
         backend.rewindBlockMetadataToHeight(height.value)
     }
 
-    /**
-     * @param limit The limit provides an efficient way how to restrict the portion of blocks, which will be validated.
-     * @return Null if successful. If an error occurs, the height will be the height where the error was detected.
-     */
-    override suspend fun validateCombinedChainOrErrorBlockHeight(limit: Long?): BlockHeight? {
-        return backend.validateCombinedChainOrErrorHeight(limit)?.let {
-            BlockHeight.new(
-                ZcashNetwork.from(backend.networkId),
-                it
-            )
-        }
-    }
-
     override suspend fun getDownloadedUtxoBalance(address: String): WalletBalance {
         // Note this implementation is not ideal because it requires two database queries without a transaction, which
         // makes the data potentially inconsistent.  However the verified amount is queried first which makes this less
@@ -162,13 +144,54 @@ internal class TypesafeBackendImpl(private val backend: Backend) : TypesafeBacke
         )
     }
 
-    override suspend fun getSentMemoAsUtf8(idNote: Long) = backend.getSentMemoAsUtf8(idNote)
-
-    override suspend fun getReceivedMemoAsUtf8(idNote: Long): String? = backend.getReceivedMemoAsUtf8(idNote)
+    override suspend fun getMemoAsUtf8(txId: ByteArray, outputIndex: Int): String? =
+        backend.getMemoAsUtf8(txId, outputIndex)
 
     override suspend fun initDataDb(seed: ByteArray?): Int = backend.initDataDb(seed)
 
-    override suspend fun scanBlocks(limit: Long?) = backend.scanBlocks(limit)
+    override suspend fun putSaplingSubtreeRoots(startIndex: Long, roots: List<SubtreeRoot>) =
+        backend.putSaplingSubtreeRoots(
+            startIndex = startIndex,
+            roots = roots.map {
+                JniSubtreeRoot.new(
+                    rootHash = it.rootHash,
+                    completingBlockHeight = it.completingBlockHeight.value
+                )
+            }
+        )
+
+    override suspend fun updateChainTip(height: BlockHeight) = backend.updateChainTip(height.value)
+
+    override suspend fun getFullyScannedHeight(): BlockHeight? {
+        return backend.getFullyScannedHeight()?.let {
+            BlockHeight.new(
+                ZcashNetwork.from(backend.networkId),
+                it
+            )
+        }
+    }
+
+    override suspend fun getMaxScannedHeight(): BlockHeight? {
+        return backend.getMaxScannedHeight()?.let {
+            BlockHeight.new(
+                ZcashNetwork.from(backend.networkId),
+                it
+            )
+        }
+    }
+
+    override suspend fun scanBlocks(fromHeight: BlockHeight, limit: Long) = backend.scanBlocks(fromHeight.value, limit)
+
+    override suspend fun getScanProgress(): ScanProgress? = backend.getScanProgress()?.let { jniScanProgress ->
+        ScanProgress.new(jniScanProgress)
+    }
+
+    override suspend fun suggestScanRanges(): List<ScanRange> = backend.suggestScanRanges().map { jniScanRange ->
+        ScanRange.new(
+            jniScanRange,
+            network
+        )
+    }
 
     override suspend fun decryptAndStoreTransaction(tx: ByteArray) = backend.decryptAndStoreTransaction(tx)
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/block/CompactBlockDownloader.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/block/CompactBlockDownloader.kt
index 6b1d7c77..2b633215 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/block/CompactBlockDownloader.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/block/CompactBlockDownloader.kt
@@ -2,7 +2,7 @@ package cash.z.ecc.android.sdk.internal.block
 
 import cash.z.ecc.android.sdk.exception.LightWalletException
 import cash.z.ecc.android.sdk.internal.Twig
-import cash.z.ecc.android.sdk.internal.ext.retryUpTo
+import cash.z.ecc.android.sdk.internal.ext.retryUpToAndThrow
 import cash.z.ecc.android.sdk.internal.model.JniBlockMeta
 import cash.z.ecc.android.sdk.internal.model.ext.from
 import cash.z.ecc.android.sdk.internal.repository.CompactBlockRepository
@@ -12,7 +12,7 @@ import co.electriccoin.lightwallet.client.model.BlockHeightUnsafe
 import co.electriccoin.lightwallet.client.model.CompactBlockUnsafe
 import co.electriccoin.lightwallet.client.model.LightWalletEndpointInfoUnsafe
 import co.electriccoin.lightwallet.client.model.Response
-import kotlinx.coroutines.Dispatchers
+import co.electriccoin.lightwallet.client.model.ShieldedProtocolEnum
 import kotlinx.coroutines.Dispatchers.IO
 import kotlinx.coroutines.flow.filterIsInstance
 import kotlinx.coroutines.flow.map
@@ -31,8 +31,7 @@ import kotlinx.coroutines.withContext
  */
 open class CompactBlockDownloader private constructor(val compactBlockRepository: CompactBlockRepository) {
 
-    lateinit var lightWalletClient: LightWalletClient
-        private set
+    private lateinit var lightWalletClient: LightWalletClient
 
     constructor(
         lightWalletClient: LightWalletClient,
@@ -112,7 +111,7 @@ open class CompactBlockDownloader private constructor(val compactBlockRepository
         compactBlockRepository.getLatestHeight()
 
     suspend fun getServerInfo(): LightWalletEndpointInfoUnsafe? = withContext(IO) {
-        retryUpTo(GET_SERVER_INFO_RETRIES) {
+        retryUpToAndThrow(GET_SERVER_INFO_RETRIES) {
             when (val response = lightWalletClient.getServerInfo()) {
                 is Response.Success -> return@withContext response.result
                 else -> {
@@ -129,11 +128,21 @@ open class CompactBlockDownloader private constructor(val compactBlockRepository
      * Stop this downloader and cleanup any resources being used.
      */
     suspend fun stop() {
-        withContext(Dispatchers.IO) {
+        withContext(IO) {
             lightWalletClient.shutdown()
         }
     }
 
+    /**
+     * Reconnect to the same or a different server. This is useful when the connection is
+     * unrecoverable. That might be time to switch to a mirror or just reconnect.
+     */
+    suspend fun reconnect() {
+        withContext(IO) {
+            lightWalletClient.reconnect()
+        }
+    }
+
     /**
      * Fetch the details of a known transaction.
      *
@@ -141,6 +150,34 @@ open class CompactBlockDownloader private constructor(val compactBlockRepository
      */
     suspend fun fetchTransaction(txId: ByteArray) = lightWalletClient.fetchTransaction(txId)
 
+    /**
+     * Fetch all UTXOs for the given addresses and from the given height.
+     *
+     * @return Flow of UTXOs for the given [tAddresses] from the [startHeight]
+     */
+    suspend fun fetchUtxos(
+        tAddresses: List<String>,
+        startHeight: BlockHeightUnsafe
+    ) = lightWalletClient.fetchUtxos(
+        tAddresses = tAddresses,
+        startHeight = startHeight
+    )
+
+    /**
+     * Returns a stream of information about roots of subtrees of the Sapling and Orchard note commitment trees.
+     *
+     * @return a flow of information about roots of subtrees of the Sapling and Orchard note commitment trees.
+     */
+    suspend fun getSubtreeRoots(
+        startIndex: Int,
+        shieldedProtocol: ShieldedProtocolEnum,
+        maxEntries: Int
+    ) = lightWalletClient.getSubtreeRoots(
+        startIndex = startIndex,
+        shieldedProtocol = shieldedProtocol,
+        maxEntries = maxEntries
+    )
+
     companion object {
         private const val GET_SERVER_INFO_RETRIES = 6
     }
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/BlockTable.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/BlockTable.kt
deleted file mode 100644
index 9f04bb33..00000000
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/BlockTable.kt
+++ /dev/null
@@ -1,88 +0,0 @@
-package cash.z.ecc.android.sdk.internal.db.derived
-
-import androidx.sqlite.db.SupportSQLiteDatabase
-import cash.z.ecc.android.sdk.internal.db.queryAndMap
-import cash.z.ecc.android.sdk.model.BlockHeight
-import cash.z.ecc.android.sdk.model.ZcashNetwork
-import kotlinx.coroutines.flow.first
-import kotlinx.coroutines.flow.firstOrNull
-import java.util.Locale
-
-internal class BlockTable(private val zcashNetwork: ZcashNetwork, private val sqliteDatabase: SupportSQLiteDatabase) {
-    companion object {
-
-        private val SELECTION_MIN_HEIGHT = arrayOf(
-            String.format(
-                Locale.ROOT,
-                "MIN(%s)", // $NON-NLS
-                BlockTableDefinition.COLUMN_LONG_HEIGHT
-            )
-        )
-
-        private val SELECTION_MAX_HEIGHT = arrayOf(
-            String.format(
-                Locale.ROOT,
-                "MAX(%s)", // $NON-NLS
-                BlockTableDefinition.COLUMN_LONG_HEIGHT
-            )
-        )
-
-        private val SELECTION_BLOCK_HEIGHT = String.format(
-            Locale.ROOT,
-            "%s = ?", // $NON-NLS
-            BlockTableDefinition.COLUMN_LONG_HEIGHT
-        )
-
-        private val PROJECTION_COUNT = arrayOf("COUNT(*)") // $NON-NLS
-
-        private val PROJECTION_HASH = arrayOf(BlockTableDefinition.COLUMN_BLOB_HASH)
-    }
-
-    suspend fun count() = sqliteDatabase.queryAndMap(
-        BlockTableDefinition.TABLE_NAME,
-        columns = PROJECTION_COUNT,
-        cursorParser = { it.getLong(0) }
-    ).first()
-
-    suspend fun firstScannedHeight(): BlockHeight {
-        // Note that we assume the Rust layer will add the birthday height as the first block
-        val heightLong =
-            sqliteDatabase.queryAndMap(
-                table = BlockTableDefinition.TABLE_NAME,
-                columns = SELECTION_MIN_HEIGHT,
-                cursorParser = { it.getLong(0) }
-            ).first()
-
-        return BlockHeight.new(zcashNetwork, heightLong)
-    }
-
-    suspend fun lastScannedHeight(): BlockHeight {
-        // Note that we assume the Rust layer will add the birthday height as the first block
-        val heightLong =
-            sqliteDatabase.queryAndMap(
-                table = BlockTableDefinition.TABLE_NAME,
-                columns = SELECTION_MAX_HEIGHT,
-                cursorParser = { it.getLong(0) }
-            ).first()
-
-        return BlockHeight.new(zcashNetwork, heightLong)
-    }
-
-    suspend fun findBlockHash(blockHeight: BlockHeight): ByteArray? {
-        return sqliteDatabase.queryAndMap(
-            table = BlockTableDefinition.TABLE_NAME,
-            columns = PROJECTION_HASH,
-            selection = SELECTION_BLOCK_HEIGHT,
-            selectionArgs = arrayOf(blockHeight.value),
-            cursorParser = { it.getBlob(0) }
-        ).firstOrNull()
-    }
-}
-
-internal object BlockTableDefinition {
-    const val TABLE_NAME = "blocks" // $NON-NLS
-
-    const val COLUMN_LONG_HEIGHT = "height" // $NON-NLS
-
-    const val COLUMN_BLOB_HASH = "hash" // $NON-NLS
-}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DbDerivedDataRepository.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DbDerivedDataRepository.kt
index 21160c9b..9d0e7710 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DbDerivedDataRepository.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DbDerivedDataRepository.kt
@@ -4,6 +4,7 @@ import cash.z.ecc.android.sdk.internal.model.DbTransactionOverview
 import cash.z.ecc.android.sdk.internal.model.EncodedTransaction
 import cash.z.ecc.android.sdk.internal.repository.DerivedDataRepository
 import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.FirstClassByteArray
 import cash.z.ecc.android.sdk.model.TransactionRecipient
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -17,24 +18,12 @@ internal class DbDerivedDataRepository(
 ) : DerivedDataRepository {
     private val invalidatingFlow = MutableStateFlow(UUID.randomUUID())
 
-    override suspend fun lastScannedHeight(): BlockHeight {
-        return derivedDataDb.blockTable.lastScannedHeight()
-    }
-
     override suspend fun firstUnenhancedHeight(): BlockHeight? {
         return derivedDataDb.allTransactionView.firstUnenhancedHeight()
     }
 
-    override suspend fun firstScannedHeight(): BlockHeight {
-        return derivedDataDb.blockTable.firstScannedHeight()
-    }
-
-    override suspend fun isInitialized(): Boolean {
-        return derivedDataDb.blockTable.count() > 0
-    }
-
-    override suspend fun findEncodedTransactionById(txId: Long): EncodedTransaction? {
-        return derivedDataDb.transactionTable.findEncodedTransactionById(txId)
+    override suspend fun findEncodedTransactionByTxId(txId: FirstClassByteArray): EncodedTransaction? {
+        return derivedDataDb.transactionTable.findEncodedTransactionByTxId(txId)
     }
 
     override suspend fun findNewTransactions(blockHeightRange: ClosedRange<BlockHeight>): List<DbTransactionOverview> =
@@ -48,8 +37,6 @@ internal class DbDerivedDataRepository(
     override suspend fun findMatchingTransactionId(rawTransactionId: ByteArray) = derivedDataDb.transactionTable
         .findDatabaseId(rawTransactionId)
 
-    override suspend fun findBlockHash(height: BlockHeight) = derivedDataDb.blockTable.findBlockHash(height)
-
     override suspend fun getTransactionCount() = derivedDataDb.transactionTable.count()
 
     override fun invalidate() {
@@ -63,7 +50,8 @@ internal class DbDerivedDataRepository(
     override val allTransactions: Flow<List<DbTransactionOverview>>
         get() = invalidatingFlow.map { derivedDataDb.allTransactionView.getAllTransactions().toList() }
 
-    override fun getNoteIds(transactionId: Long) = derivedDataDb.txOutputsView.getNoteIds(transactionId)
+    override fun getSaplingOutputIndices(transactionId: Long) =
+        derivedDataDb.txOutputsView.getSaplingOutputIndices(transactionId)
 
     override fun getRecipients(transactionId: Long): Flow<TransactionRecipient> {
         return derivedDataDb.txOutputsView.getRecipients(transactionId)
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DerivedDataDb.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DerivedDataDb.kt
index 06656faa..945a18cb 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DerivedDataDb.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/DerivedDataDb.kt
@@ -2,13 +2,13 @@ package cash.z.ecc.android.sdk.internal.db.derived
 
 import android.content.Context
 import androidx.sqlite.db.SupportSQLiteDatabase
+import cash.z.ecc.android.sdk.exception.CompactBlockProcessorException
 import cash.z.ecc.android.sdk.internal.NoBackupContextWrapper
 import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.internal.TypesafeBackend
 import cash.z.ecc.android.sdk.internal.db.ReadOnlySupportSqliteOpenHelper
-import cash.z.ecc.android.sdk.internal.ext.tryWarn
 import cash.z.ecc.android.sdk.internal.model.Checkpoint
-import cash.z.ecc.android.sdk.model.UnifiedFullViewingKey
+import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.ZcashNetwork
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
@@ -20,8 +20,6 @@ internal class DerivedDataDb private constructor(
 ) {
     val accountTable = AccountTable(sqliteDatabase)
 
-    val blockTable = BlockTable(zcashNetwork, sqliteDatabase)
-
     val transactionTable = TransactionTable(zcashNetwork, sqliteDatabase)
 
     val allTransactionView = AllTransactionView(zcashNetwork, sqliteDatabase)
@@ -39,7 +37,7 @@ internal class DerivedDataDb private constructor(
         // SqliteOpenHelper is happy
         private const val DATABASE_VERSION = 8
 
-        @Suppress("LongParameterList", "SpreadOperator")
+        @Suppress("LongParameterList")
         suspend fun new(
             context: Context,
             backend: TypesafeBackend,
@@ -47,27 +45,16 @@ internal class DerivedDataDb private constructor(
             zcashNetwork: ZcashNetwork,
             checkpoint: Checkpoint,
             seed: ByteArray?,
-            viewingKeys: List<UnifiedFullViewingKey>
+            numberOfAccounts: Int,
+            recoverUntil: BlockHeight?
         ): DerivedDataDb {
-            backend.initDataDb(seed)
-
             runCatching {
-                // TODO [#681]: consider converting these to typed exceptions in the welding layer
-                // TODO [#681]: https://github.com/zcash/zcash-android-wallet-sdk/issues/681
-                tryWarn(
-                    message = "Did not initialize the blocks table. It probably was already initialized.",
-                    ifContains = "table is not empty"
-                ) {
-                    backend.initBlocksTable(checkpoint)
-                }
-                tryWarn(
-                    message = "Did not initialize the accounts table. It probably was already initialized.",
-                    ifContains = "table is not empty"
-                ) {
-                    backend.initAccountsTable(*viewingKeys.toTypedArray())
+                val result = backend.initDataDb(seed)
+                if (result < 0) {
+                    throw CompactBlockProcessorException.Uninitialized()
                 }
             }.onFailure {
-                Twig.error { "Failed to init derived data database with $it" }
+                throw CompactBlockProcessorException.Uninitialized(it)
             }
 
             val database = ReadOnlySupportSqliteOpenHelper.openExistingDatabaseAsReadOnly(
@@ -79,7 +66,29 @@ internal class DerivedDataDb private constructor(
                 DATABASE_VERSION
             )
 
-            return DerivedDataDb(zcashNetwork, database)
+            val dataDb = DerivedDataDb(zcashNetwork, database)
+
+            // If a seed is provided, fill in the accounts.
+            seed?.let { checkedSeed ->
+                // toInt() should be safe because we expect very few accounts
+                val missingAccounts = numberOfAccounts - dataDb.accountTable.count().toInt()
+                require(missingAccounts >= 0) {
+                    "Unexpected number of accounts: $missingAccounts"
+                }
+                repeat(missingAccounts) {
+                    runCatching {
+                        backend.createAccountAndGetSpendingKey(
+                            seed = checkedSeed,
+                            treeState = checkpoint.treeState(),
+                            recoverUntil = recoverUntil
+                        )
+                    }.onFailure {
+                        Twig.error(it) { "Create account failed." }
+                    }
+                }
+            }
+
+            return dataDb
         }
     }
 }
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TransactionTable.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TransactionTable.kt
index 48cee81a..ed99bb02 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TransactionTable.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TransactionTable.kt
@@ -45,7 +45,7 @@ internal class TransactionTable(
         private val SELECTION_TRANSACTION_ID_AND_RAW_NOT_NULL = String.format(
             Locale.ROOT,
             "%s = ? AND %s IS NOT NULL", // $NON-NLS
-            TransactionTableDefinition.COLUMN_INTEGER_ID,
+            TransactionTableDefinition.COLUMN_BLOB_TRANSACTION_ID,
             TransactionTableDefinition.COLUMN_BLOB_RAW
         )
     }
@@ -66,18 +66,16 @@ internal class TransactionTable(
             cursorParser = { it.getLong(0) }
         ).first()
 
-    suspend fun findEncodedTransactionById(id: Long): EncodedTransaction? {
+    suspend fun findEncodedTransactionByTxId(txId: FirstClassByteArray): EncodedTransaction? {
         return sqliteDatabase.queryAndMap(
             table = TransactionTableDefinition.TABLE_NAME,
             columns = PROJECTION_ENCODED_TRANSACTION,
             selection = SELECTION_TRANSACTION_ID_AND_RAW_NOT_NULL,
-            selectionArgs = arrayOf(id)
+            selectionArgs = arrayOf(txId.byteArray)
         ) {
-            val txIdIndex = it.getColumnIndexOrThrow(TransactionTableDefinition.COLUMN_BLOB_TRANSACTION_ID)
             val rawIndex = it.getColumnIndexOrThrow(TransactionTableDefinition.COLUMN_BLOB_RAW)
             val heightIndex = it.getColumnIndexOrThrow(TransactionTableDefinition.COLUMN_INTEGER_EXPIRY_HEIGHT)
 
-            val txid = it.getBlob(txIdIndex)
             val raw = it.getBlob(rawIndex)
             val expiryHeight = if (it.isNull(heightIndex)) {
                 null
@@ -86,7 +84,7 @@ internal class TransactionTable(
             }
 
             EncodedTransaction(
-                FirstClassByteArray(txid),
+                txId,
                 FirstClassByteArray(raw),
                 expiryHeight
             )
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TxOutputsView.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TxOutputsView.kt
index becc0554..4a150ca3 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TxOutputsView.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/db/derived/TxOutputsView.kt
@@ -20,7 +20,7 @@ internal class TxOutputsView(
             TxOutputsViewDefinition.COLUMN_INTEGER_TRANSACTION_ID
         )
 
-        private val PROJECTION_ID = arrayOf(TxOutputsViewDefinition.COLUMN_INTEGER_TRANSACTION_ID)
+        private val PROJECTION_OUTPUT_INDEX = arrayOf(TxOutputsViewDefinition.COLUMN_INTEGER_OUTPUT_INDEX)
 
         private val PROJECTION_RECIPIENT = arrayOf(
             TxOutputsViewDefinition.COLUMN_STRING_TO_ADDRESS,
@@ -35,17 +35,17 @@ internal class TxOutputsView(
         )
     }
 
-    fun getNoteIds(transactionId: Long) =
+    fun getSaplingOutputIndices(transactionId: Long) =
         sqliteDatabase.queryAndMap(
             table = TxOutputsViewDefinition.VIEW_NAME,
-            columns = PROJECTION_ID,
+            columns = PROJECTION_OUTPUT_INDEX,
             selection = SELECT_BY_TRANSACTION_ID_AND_NOT_CHANGE,
             selectionArgs = arrayOf(transactionId),
             orderBy = ORDER_BY,
             cursorParser = {
-                val idColumnIndex = it.getColumnIndex(TxOutputsViewDefinition.COLUMN_INTEGER_TRANSACTION_ID)
+                val idColumnOutputIndex = it.getColumnIndex(TxOutputsViewDefinition.COLUMN_INTEGER_OUTPUT_INDEX)
 
-                it.getLong(idColumnIndex)
+                it.getInt(idColumnOutputIndex)
             }
         )
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/Ext.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/ExceptionExt.kt
similarity index 56%
rename from sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/Ext.kt
rename to sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/ExceptionExt.kt
index 27a1f7cd..b87426c2 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/Ext.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/ExceptionExt.kt
@@ -44,3 +44,30 @@ internal inline fun <R> tryWarn(
         }
     }
 }
+
+// Note: Do NOT change these texts as they match the ones from ScanError in
+// librustzcash/zcash_client_backend/src/scanning.rs
+internal const val PREV_HASH_MISMATCH = "The parent hash of proposed block does not correspond to the block hash at " +
+    "height" // $NON-NLS
+internal const val BLOCK_HEIGHT_DISCONTINUITY = "Block height discontinuity at height" // $NON-NLS
+internal const val TREE_SIZE_MISMATCH = "note commitment tree size provided by a compact block did not match the " +
+    "expected size at height" // $NON-NLS
+
+/**
+ * Check whether this error is the result of a failed continuity while scanning new blocks in the Rust layer.
+ *
+ * @return true in case of the check match, false otherwise
+ */
+internal fun Throwable.isScanContinuityError(): Boolean {
+    val errorMessages = listOf(
+        PREV_HASH_MISMATCH,
+        BLOCK_HEIGHT_DISCONTINUITY,
+        TREE_SIZE_MISMATCH
+    )
+    errorMessages.forEach { errMessage ->
+        if (this.message?.lowercase()?.contains(errMessage.lowercase()) == true) {
+            return true
+        }
+    }
+    return false
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/WalletService.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/WalletService.kt
index 2c96644d..75aca6e5 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/WalletService.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/ext/WalletService.kt
@@ -1,10 +1,9 @@
 package cash.z.ecc.android.sdk.internal.ext
 
-import android.content.Context
 import cash.z.ecc.android.sdk.ext.ZcashSdk.MAX_BACKOFF_INTERVAL
 import cash.z.ecc.android.sdk.internal.Twig
 import kotlinx.coroutines.delay
-import java.io.File
+import kotlin.math.pow
 import kotlin.random.Random
 
 /**
@@ -18,7 +17,7 @@ import kotlin.random.Random
  * @param block the code to execute, which will be wrapped in a try/catch and retried whenever an
  * exception is thrown up to [retries] attempts.
  */
-suspend inline fun retryUpTo(
+suspend inline fun retryUpToAndThrow(
     retries: Int,
     exceptionWrapper: (Throwable) -> Throwable = { it },
     initialDelayMillis: Long = 500L,
@@ -35,7 +34,43 @@ suspend inline fun retryUpTo(
             if (failedAttempts > retries) {
                 throw exceptionWrapper(t)
             }
-            val duration = (initialDelayMillis.toDouble() * Math.pow(2.0, failedAttempts.toDouble() - 1)).toLong()
+            val duration = (initialDelayMillis.toDouble() * 2.0.pow(failedAttempts.toDouble() - 1)).toLong()
+            Twig.warn(t) { "Retrying ($failedAttempts/$retries) in ${duration}s..." }
+            delay(duration)
+        }
+    }
+}
+
+/**
+ * Execute the given block and if it fails, retry up to [retries] more times. If none of the
+ * retries succeed, then leave the block execution unfinished and continue.
+ *
+ * @param retries the number of times to retry the block after the first attempt fails.
+ * @param exceptionWrapper a function that can wrap the final failure to add more useful information
+ *  * or context. Default behavior is to just return the final exception.
+ * @param initialDelayMillis the initial amount of time to wait before the first retry.
+ * @param block the code to execute, which will be wrapped in a try/catch and retried whenever an
+ * exception is thrown up to [retries] attempts.
+ */
+suspend inline fun retryUpToAndContinue(
+    retries: Int,
+    exceptionWrapper: (Throwable) -> Throwable = { it },
+    initialDelayMillis: Long = 500L,
+    block: (Int) -> Unit
+) {
+    var failedAttempts = 0
+    while (failedAttempts < retries) {
+        @Suppress("TooGenericExceptionCaught")
+        try {
+            block(failedAttempts)
+            return
+        } catch (t: Throwable) {
+            failedAttempts++
+            if (failedAttempts == retries) {
+                exceptionWrapper(t)
+                return
+            }
+            val duration = (initialDelayMillis.toDouble() * 2.0.pow(failedAttempts.toDouble() - 1)).toLong()
             Twig.warn(t) { "Retrying ($failedAttempts/$retries) in ${duration}s..." }
             delay(duration)
         }
@@ -73,10 +108,8 @@ suspend inline fun retryWithBackoff(
 
             sequence++
             // initialDelay^(sequence/4) + jitter
-            var duration = Math.pow(
-                initialDelayMillis.toDouble(),
-                (sequence.toDouble() / 4.0)
-            ).toLong() + Random.nextLong(1000L)
+            var duration = initialDelayMillis.toDouble().pow((sequence.toDouble() / 4.0)).toLong() +
+                Random.nextLong(1000L)
             if (duration > maxDelayMillis) {
                 duration = maxDelayMillis - Random.nextLong(1000L) // include jitter but don't exceed max delay
                 sequence /= 2
@@ -86,12 +119,3 @@ suspend inline fun retryWithBackoff(
         }
     }
 }
-
-/**
- * Return true if the given database already exists.
- *
- * @return true when the given database exists in the given context.
- */
-internal fun dbExists(appContext: Context, dbFileName: String): Boolean {
-    return File(appContext.getDatabasePath(dbFileName).absolutePath).exists()
-}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/Checkpoint.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/Checkpoint.kt
index d42acfb3..ee3a72de 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/Checkpoint.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/Checkpoint.kt
@@ -1,5 +1,6 @@
 package cash.z.ecc.android.sdk.internal.model
 
+import cash.z.ecc.android.sdk.internal.ext.isInUIntRange
 import cash.z.ecc.android.sdk.model.BlockHeight
 
 /**
@@ -18,5 +19,12 @@ internal data class Checkpoint(
     // Note: this field does NOT match the name of the JSON, so will break with field-based JSON parsing
     val tree: String
 ) {
+    fun treeState(): TreeState {
+        require(epochSeconds.isInUIntRange()) {
+            "epochSeconds $epochSeconds is outside of allowed UInt range"
+        }
+        return TreeState.fromParts(height.value, hash, epochSeconds.toInt(), tree)
+    }
+
     internal companion object
 }
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/ScanProgress.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/ScanProgress.kt
new file mode 100644
index 00000000..79f4cd79
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/ScanProgress.kt
@@ -0,0 +1,28 @@
+package cash.z.ecc.android.sdk.internal.model
+
+internal data class ScanProgress(
+    private val numerator: Long,
+    private val denominator: Long
+) {
+    override fun toString() = "ScanProgress($numerator/$denominator) -> ${getSafeRation()}"
+
+    /**
+     * Returns progress ratio in [0, 1] range. Any out-of-range value is treated as 0.
+     */
+    fun getSafeRation() = numerator.toFloat().div(denominator).let { ration ->
+        if (ration < 0f || ration > 1f) {
+            0f
+        } else {
+            ration
+        }
+    }
+
+    companion object {
+        fun new(jni: JniScanProgress): ScanProgress {
+            return ScanProgress(
+                numerator = jni.numerator,
+                denominator = jni.denominator
+            )
+        }
+    }
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/ScanRange.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/ScanRange.kt
new file mode 100644
index 00000000..adfc5b16
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/ScanRange.kt
@@ -0,0 +1,41 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+
+internal data class ScanRange(
+    val range: ClosedRange<BlockHeight>,
+    val priority: Long
+) {
+    override fun toString() = "ScanRange(range=$range, priority=${getSuggestScanRangePriority()})"
+
+    internal fun getSuggestScanRangePriority(): SuggestScanRangePriority {
+        return SuggestScanRangePriority.entries
+            .firstOrNull { it.priority == priority } ?: SuggestScanRangePriority.Ignored
+    }
+
+    companion object {
+        /**
+         *  Note that this function subtracts 1 from [JniScanRange.endHeight] as the rest of the logic works with
+         *  [ClosedRange] and the endHeight is exclusive.
+         */
+        fun new(jni: JniScanRange, zcashNetwork: ZcashNetwork): ScanRange {
+            return ScanRange(
+                range =
+                BlockHeight.new(zcashNetwork, jni.startHeight)..(BlockHeight.new(zcashNetwork, jni.endHeight) - 1),
+                priority = jni.priority
+            )
+        }
+    }
+}
+
+@Suppress("MagicNumber")
+internal enum class SuggestScanRangePriority(val priority: Long) {
+    Ignored(0),
+    Scanned(10),
+    Historic(20),
+    OpenAdjacent(30),
+    FoundNote(40),
+    ChainTip(50),
+    Verify(60)
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/SubtreeRoot.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/SubtreeRoot.kt
new file mode 100644
index 00000000..a58306ed
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/SubtreeRoot.kt
@@ -0,0 +1,43 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+import co.electriccoin.lightwallet.client.model.SubtreeRootUnsafe
+
+internal data class SubtreeRoot(
+    val rootHash: ByteArray,
+    val completingBlockHash: ByteArray,
+    val completingBlockHeight: BlockHeight
+) {
+    override fun toString() = "SubtreeRoot(completingBlockHeight=${completingBlockHeight.value})"
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (javaClass != other?.javaClass) return false
+
+        other as SubtreeRoot
+
+        if (!rootHash.contentEquals(other.rootHash)) return false
+        if (!completingBlockHash.contentEquals(other.completingBlockHash)) return false
+        if (completingBlockHeight != other.completingBlockHeight) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        var result = rootHash.contentHashCode()
+        result = 31 * result + completingBlockHash.contentHashCode()
+        result = 31 * result + completingBlockHeight.hashCode()
+        return result
+    }
+
+    companion object {
+        fun new(unsafe: SubtreeRootUnsafe, zcashNetwork: ZcashNetwork): SubtreeRoot {
+            return SubtreeRoot(
+                rootHash = unsafe.rootHash,
+                completingBlockHash = unsafe.completingBlockHash,
+                completingBlockHeight = BlockHeight.new(zcashNetwork, unsafe.completingBlockHeight.value)
+            )
+        }
+    }
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/TreeState.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/TreeState.kt
new file mode 100644
index 00000000..927db67c
--- /dev/null
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/model/TreeState.kt
@@ -0,0 +1,26 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import co.electriccoin.lightwallet.client.model.TreeStateUnsafe
+
+class TreeState(
+    val encoded: ByteArray
+) {
+    companion object {
+        fun new(unsafe: TreeStateUnsafe): TreeState {
+            // Potential validation comes here
+            return TreeState(
+                encoded = unsafe.encoded
+            )
+        }
+
+        fun fromParts(
+            height: Long,
+            hash: String,
+            time: Int,
+            tree: String
+        ): TreeState {
+            val unsafeTreeState = TreeStateUnsafe.fromParts(height, hash, time, tree)
+            return TreeState.new(unsafeTreeState)
+        }
+    }
+}
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/repository/DerivedDataRepository.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/repository/DerivedDataRepository.kt
index b20da0e8..b0821771 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/repository/DerivedDataRepository.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/repository/DerivedDataRepository.kt
@@ -3,6 +3,7 @@ package cash.z.ecc.android.sdk.internal.repository
 import cash.z.ecc.android.sdk.internal.model.DbTransactionOverview
 import cash.z.ecc.android.sdk.internal.model.EncodedTransaction
 import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.FirstClassByteArray
 import cash.z.ecc.android.sdk.model.TransactionRecipient
 import kotlinx.coroutines.flow.Flow
 
@@ -12,13 +13,6 @@ import kotlinx.coroutines.flow.Flow
 @Suppress("TooManyFunctions")
 internal interface DerivedDataRepository {
 
-    /**
-     * The last height scanned by this repository.
-     *
-     * @return the last height scanned by this repository.
-     */
-    suspend fun lastScannedHeight(): BlockHeight
-
     /**
      * The height of the first transaction that hasn't been enhanced yet.
      *
@@ -27,18 +21,6 @@ internal interface DerivedDataRepository {
      */
     suspend fun firstUnenhancedHeight(): BlockHeight?
 
-    /**
-     * The height of the first block in this repository. This is typically the checkpoint that was
-     * used to initialize this wallet. If we overwrite this block, it breaks our ability to spend
-     * funds.
-     */
-    suspend fun firstScannedHeight(): BlockHeight
-
-    /**
-     * @return true when this repository has been initialized and seeded with the initial checkpoint.
-     */
-    suspend fun isInitialized(): Boolean
-
     /**
      * Find the encoded transaction associated with the given id.
      *
@@ -46,7 +28,7 @@ internal interface DerivedDataRepository {
      *
      * @return the transaction or null when it cannot be found.
      */
-    suspend fun findEncodedTransactionById(txId: Long): EncodedTransaction?
+    suspend fun findEncodedTransactionByTxId(txId: FirstClassByteArray): EncodedTransaction?
 
     /**
      * Find all the newly scanned transactions in the given range, including transactions (like
@@ -75,11 +57,6 @@ internal interface DerivedDataRepository {
 
     suspend fun findMatchingTransactionId(rawTransactionId: ByteArray): Long?
 
-    // TODO [#681]: begin converting these into Data Access API. For now, just collect the desired
-    //  operations and iterate/refactor, later
-    // TODO [#681]: https://github.com/zcash/zcash-android-wallet-sdk/issues/681
-    suspend fun findBlockHash(height: BlockHeight): ByteArray?
-
     suspend fun getTransactionCount(): Long
 
     /**
@@ -105,7 +82,7 @@ internal interface DerivedDataRepository {
 
     val allTransactions: Flow<List<DbTransactionOverview>>
 
-    fun getNoteIds(transactionId: Long): Flow<Long>
+    fun getSaplingOutputIndices(transactionId: Long): Flow<Int>
 
     fun getRecipients(transactionId: Long): Flow<TransactionRecipient>
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/storage/block/FileCompactBlockRepository.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/storage/block/FileCompactBlockRepository.kt
index d74441cc..4ce75751 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/storage/block/FileCompactBlockRepository.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/storage/block/FileCompactBlockRepository.kt
@@ -25,7 +25,7 @@ internal class FileCompactBlockRepository(
     private val backend: TypesafeBackend
 ) : CompactBlockRepository {
 
-    override suspend fun getLatestHeight() = backend.getLatestBlockHeight()
+    override suspend fun getLatestHeight() = backend.getLatestCacheHeight()
 
     override suspend fun findCompactBlock(height: BlockHeight) = backend.findBlockMetadata(height)
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoder.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoder.kt
index 97bd5185..4a5383e9 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoder.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoder.kt
@@ -1,6 +1,7 @@
 package cash.z.ecc.android.sdk.internal.transaction
 
 import cash.z.ecc.android.sdk.internal.model.EncodedTransaction
+import cash.z.ecc.android.sdk.model.BlockHeight
 import cash.z.ecc.android.sdk.model.TransactionRecipient
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.Zatoshi
@@ -69,6 +70,10 @@ internal interface TransactionEncoder {
 
     /**
      * Return the consensus branch that the encoder is using when making transactions.
+     *
+     * @param height the height at which we want to get the consensus branch
+     *
+     * @return id of consensus branch
      */
-    suspend fun getConsensusBranchId(): Long
+    suspend fun getConsensusBranchId(height: BlockHeight): Long
 }
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoderImpl.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoderImpl.kt
index c43016a4..e174a20d 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoderImpl.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/transaction/TransactionEncoderImpl.kt
@@ -7,6 +7,8 @@ import cash.z.ecc.android.sdk.internal.Twig
 import cash.z.ecc.android.sdk.internal.TypesafeBackend
 import cash.z.ecc.android.sdk.internal.model.EncodedTransaction
 import cash.z.ecc.android.sdk.internal.repository.DerivedDataRepository
+import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.FirstClassByteArray
 import cash.z.ecc.android.sdk.model.TransactionRecipient
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.Zatoshi
@@ -47,7 +49,7 @@ internal class TransactionEncoderImpl(
         require(recipient is TransactionRecipient.Address)
 
         val transactionId = createSpend(usk, amount, recipient.addressValue, memo)
-        return repository.findEncodedTransactionById(transactionId)
+        return repository.findEncodedTransactionByTxId(transactionId)
             ?: throw TransactionEncoderException.TransactionNotFoundException(transactionId)
     }
 
@@ -59,7 +61,7 @@ internal class TransactionEncoderImpl(
         require(recipient is TransactionRecipient.Account)
 
         val transactionId = createShieldingSpend(usk, memo)
-        return repository.findEncodedTransactionById(transactionId)
+        return repository.findEncodedTransactionByTxId(transactionId)
             ?: throw TransactionEncoderException.TransactionNotFoundException(transactionId)
     }
 
@@ -96,8 +98,16 @@ internal class TransactionEncoderImpl(
     override suspend fun isValidUnifiedAddress(address: String): Boolean =
         backend.isValidUnifiedAddr(address)
 
-    override suspend fun getConsensusBranchId(): Long {
-        val height = repository.lastScannedHeight()
+    /**
+     * Return the consensus branch that the encoder is using when making transactions.
+     *
+     * @param height the height at which we want to get the consensus branch
+     *
+     * @return id of consensus branch
+     *
+     * @throws TransactionEncoderException.IncompleteScanException if the [height] is less than activation height
+     */
+    override suspend fun getConsensusBranchId(height: BlockHeight): Long {
         if (height < backend.network.saplingActivationHeight) {
             throw TransactionEncoderException.IncompleteScanException(height)
         }
@@ -121,10 +131,10 @@ internal class TransactionEncoderImpl(
         amount: Zatoshi,
         toAddress: String,
         memo: ByteArray? = byteArrayOf()
-    ): Long {
+    ): FirstClassByteArray {
         Twig.debug {
             "creating transaction to spend $amount zatoshi to" +
-                " ${toAddress.masked()} with memo $memo"
+                " ${toAddress.masked()} with memo: ${memo?.decodeToString()}"
         }
 
         @Suppress("TooGenericExceptionCaught")
@@ -148,7 +158,7 @@ internal class TransactionEncoderImpl(
     private suspend fun createShieldingSpend(
         usk: UnifiedSpendingKey,
         memo: ByteArray? = byteArrayOf()
-    ): Long {
+    ): FirstClassByteArray {
         @Suppress("TooGenericExceptionCaught")
         return try {
             saplingParamTool.ensureParams(saplingParamTool.properties.paramsDirectory)
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/BlockHeight.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/BlockHeight.kt
index 9e66c184..ed4b42ef 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/BlockHeight.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/BlockHeight.kt
@@ -39,6 +39,24 @@ data class BlockHeight internal constructor(val value: Long) : Comparable<BlockH
         return BlockHeight(value + other)
     }
 
+    operator fun minus(other: BlockHeight) = BlockHeight(value - other.value)
+
+    operator fun minus(other: Int): BlockHeight {
+        require(other >= 0) {
+            "Cannot subtract negative value $other to BlockHeight"
+        }
+
+        return BlockHeight(value - other.toLong())
+    }
+
+    operator fun minus(other: Long): BlockHeight {
+        require(other >= 0) {
+            "Cannot subtract negative value $other to BlockHeight"
+        }
+
+        return BlockHeight(value - other)
+    }
+
     companion object {
         private val UINT_RANGE = 0.toLong()..UInt.MAX_VALUE.toLong()
 
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/TransactionOverview.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/TransactionOverview.kt
index 0a783572..6bac5fe6 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/TransactionOverview.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/TransactionOverview.kt
@@ -33,7 +33,7 @@ data class TransactionOverview internal constructor(
     companion object {
         internal fun new(
             dbTransactionOverview: DbTransactionOverview,
-            latestBlockHeight: BlockHeight
+            latestBlockHeight: BlockHeight?
         ): TransactionOverview {
             return TransactionOverview(
                 dbTransactionOverview.id,
@@ -69,11 +69,13 @@ enum class TransactionState {
 
         private const val MIN_CONFIRMATIONS = 10
         internal fun new(
-            latestBlockHeight: BlockHeight,
+            latestBlockHeight: BlockHeight?,
             minedHeight: BlockHeight?,
             expiryHeight: BlockHeight?
         ): TransactionState {
-            return if (minedHeight != null && (latestBlockHeight.value - minedHeight.value) >= MIN_CONFIRMATIONS) {
+            return if (latestBlockHeight == null) {
+                Pending
+            } else if (minedHeight != null && (latestBlockHeight.value - minedHeight.value) >= MIN_CONFIRMATIONS) {
                 Confirmed
             } else if (minedHeight != null && (latestBlockHeight.value - minedHeight.value) < MIN_CONFIRMATIONS) {
                 Pending
diff --git a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/ZcashNetwork.kt b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/ZcashNetwork.kt
index 2844a6a8..ead0b1c3 100644
--- a/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/ZcashNetwork.kt
+++ b/sdk-lib/src/main/java/cash/z/ecc/android/sdk/model/ZcashNetwork.kt
@@ -11,6 +11,9 @@ data class ZcashNetwork(
     val saplingActivationHeight: BlockHeight,
     val orchardActivationHeight: BlockHeight
 ) {
+    fun isMainnet() = id == ID_MAINNET
+
+    fun isTestnet() = id == ID_TESTNET
 
     @Suppress("MagicNumber")
     companion object {
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessorTest.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessorTest.kt
new file mode 100644
index 00000000..1df6c35c
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/block/processor/CompactBlockProcessorTest.kt
@@ -0,0 +1,30 @@
+package cash.z.ecc.android.sdk.block.processor
+
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class CompactBlockProcessorTest {
+
+    @Test
+    fun should_refresh_preparation_test() {
+        assertTrue {
+            CompactBlockProcessor.shouldRefreshPreparation(
+                lastPreparationTime = CompactBlockProcessor.SYNCHRONIZATION_RESTART_TIMEOUT,
+                currentTimeMillis = CompactBlockProcessor.SYNCHRONIZATION_RESTART_TIMEOUT * 2,
+                limitTime = CompactBlockProcessor.SYNCHRONIZATION_RESTART_TIMEOUT
+            )
+        }
+    }
+
+    @Test
+    fun should_not_refresh_preparation_test() {
+        assertFalse {
+            CompactBlockProcessor.shouldRefreshPreparation(
+                lastPreparationTime = CompactBlockProcessor.SYNCHRONIZATION_RESTART_TIMEOUT,
+                currentTimeMillis = CompactBlockProcessor.SYNCHRONIZATION_RESTART_TIMEOUT,
+                limitTime = CompactBlockProcessor.SYNCHRONIZATION_RESTART_TIMEOUT
+            )
+        }
+    }
+}
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/ext/ExceptionExtTest.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/ext/ExceptionExtTest.kt
new file mode 100644
index 00000000..1288d9a2
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/ext/ExceptionExtTest.kt
@@ -0,0 +1,30 @@
+package cash.z.ecc.android.sdk.ext
+
+import cash.z.ecc.android.sdk.internal.ext.BLOCK_HEIGHT_DISCONTINUITY
+import cash.z.ecc.android.sdk.internal.ext.PREV_HASH_MISMATCH
+import cash.z.ecc.android.sdk.internal.ext.TREE_SIZE_MISMATCH
+import cash.z.ecc.android.sdk.internal.ext.isScanContinuityError
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class ExceptionExtTest {
+
+    @Test
+    fun is_scan_continuity_error() {
+        assertTrue { RuntimeException(PREV_HASH_MISMATCH).isScanContinuityError() }
+        assertTrue { RuntimeException(TREE_SIZE_MISMATCH).isScanContinuityError() }
+        assertTrue { RuntimeException(BLOCK_HEIGHT_DISCONTINUITY).isScanContinuityError() }
+
+        assertTrue { RuntimeException(PREV_HASH_MISMATCH.lowercase()).isScanContinuityError() }
+
+        assertTrue { RuntimeException(PREV_HASH_MISMATCH.plus("Text")).isScanContinuityError() }
+    }
+
+    @Test
+    fun is_not_scan_continuity_error() {
+        assertFalse { RuntimeException("Text").isScanContinuityError() }
+        assertFalse { RuntimeException("").isScanContinuityError() }
+        assertFalse { RuntimeException(PREV_HASH_MISMATCH.drop(1)).isScanContinuityError() }
+    }
+}
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/fixture/ScanProgressFixture.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/fixture/ScanProgressFixture.kt
new file mode 100644
index 00000000..f3fd93b2
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/fixture/ScanProgressFixture.kt
@@ -0,0 +1,13 @@
+package cash.z.ecc.android.sdk.fixture
+
+import cash.z.ecc.android.sdk.internal.model.ScanProgress
+
+object ScanProgressFixture {
+    internal const val DEFAULT_NUMERATOR = 50L
+    internal const val DEFAULT_DENOMINATOR = 100L
+
+    internal fun new(
+        numerator: Long = DEFAULT_NUMERATOR,
+        denominator: Long = DEFAULT_DENOMINATOR
+    ) = ScanProgress(numerator, denominator)
+}
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/fixture/ScanRangeFixture.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/fixture/ScanRangeFixture.kt
new file mode 100644
index 00000000..249dc099
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/fixture/ScanRangeFixture.kt
@@ -0,0 +1,17 @@
+package cash.z.ecc.android.sdk.fixture
+
+import cash.z.ecc.android.sdk.internal.model.ScanRange
+import cash.z.ecc.android.sdk.internal.model.SuggestScanRangePriority
+import cash.z.ecc.android.sdk.model.BlockHeight
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+
+object ScanRangeFixture {
+    internal val DEFAULT_CLOSED_RANGE =
+        ZcashNetwork.Testnet.saplingActivationHeight..ZcashNetwork.Testnet.saplingActivationHeight + 9
+    internal val DEFAULT_PRIORITY = SuggestScanRangePriority.Verify.priority
+
+    internal fun new(
+        range: ClosedRange<BlockHeight> = DEFAULT_CLOSED_RANGE,
+        priority: Long = DEFAULT_PRIORITY
+    ) = ScanRange(range, priority)
+}
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/ScanProgressTest.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/ScanProgressTest.kt
new file mode 100644
index 00000000..826e5051
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/ScanProgressTest.kt
@@ -0,0 +1,24 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import cash.z.ecc.android.sdk.fixture.ScanProgressFixture
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+class ScanProgressTest {
+    @Test
+    fun get_valid_ratio_test() {
+        val scanProgress = ScanProgressFixture.new()
+        assertEquals(
+            scanProgress.getSafeRation(),
+            ScanProgressFixture.DEFAULT_NUMERATOR.toFloat().div(ScanProgressFixture.DEFAULT_DENOMINATOR)
+        )
+    }
+
+    @Test
+    fun get_fallback_ratio_test() {
+        val scanProgress = ScanProgressFixture.new(
+            denominator = 0
+        )
+        assertEquals(0f, scanProgress.getSafeRation())
+    }
+}
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/ScanRangeTest.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/ScanRangeTest.kt
new file mode 100644
index 00000000..20f6580a
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/internal/model/ScanRangeTest.kt
@@ -0,0 +1,29 @@
+package cash.z.ecc.android.sdk.internal.model
+
+import cash.z.ecc.android.sdk.fixture.ScanRangeFixture
+import cash.z.ecc.android.sdk.internal.ext.isNotEmpty
+import cash.z.ecc.android.sdk.internal.ext.length
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+import kotlin.test.Test
+import kotlin.test.assertTrue
+
+class ScanRangeTest {
+    @Test
+    fun get_suggest_scan_range_priority_test() {
+        val scanRange = ScanRangeFixture.new(
+            priority = SuggestScanRangePriority.Verify.priority
+        )
+        assertTrue {
+            scanRange.getSuggestScanRangePriority() == SuggestScanRangePriority.Verify
+        }
+    }
+
+    @Test
+    fun scan_range_boundaries_test() {
+        val scanRange = ScanRangeFixture.new(
+            range = ZcashNetwork.Testnet.saplingActivationHeight..ZcashNetwork.Testnet.saplingActivationHeight + 9
+        )
+        assertTrue { scanRange.range.isNotEmpty() }
+        assertTrue { scanRange.range.length() == 10L }
+    }
+}
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/BlockHeightTest.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/BlockHeightTest.kt
index 4290bceb..295bf109 100644
--- a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/BlockHeightTest.kt
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/BlockHeightTest.kt
@@ -68,4 +68,32 @@ class BlockHeightTest {
             ZcashNetwork.Mainnet.saplingActivationHeight + -1L
         }
     }
+
+    @Test
+    fun subtraction_of_block_height_succeeds() {
+        val one = BlockHeight.new(
+            ZcashNetwork.Mainnet,
+            ZcashNetwork.Mainnet.saplingActivationHeight.value +
+                ZcashNetwork.Mainnet.saplingActivationHeight.value
+        )
+        val two = BlockHeight.new(ZcashNetwork.Mainnet, ZcashNetwork.Mainnet.saplingActivationHeight.value)
+
+        assertEquals(ZcashNetwork.Mainnet.saplingActivationHeight.value, (one - two).value)
+    }
+
+    @Test
+    fun subtraction_of_long_succeeds() {
+        assertEquals(
+            ZcashNetwork.Mainnet.saplingActivationHeight.value,
+            (BlockHeight(419_323L) - 123L).value
+        )
+    }
+
+    @Test
+    fun subtraction_of_int_succeeds() {
+        assertEquals(
+            ZcashNetwork.Mainnet.saplingActivationHeight.value,
+            (BlockHeight(419_323) - 123).value
+        )
+    }
 }
diff --git a/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/ZcashNetworkTest.kt b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/ZcashNetworkTest.kt
new file mode 100644
index 00000000..b20638be
--- /dev/null
+++ b/sdk-lib/src/test/java/cash/z/ecc/android/sdk/model/ZcashNetworkTest.kt
@@ -0,0 +1,28 @@
+package cash.z.ecc.android.sdk.model
+
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class ZcashNetworkTest {
+
+    @Test
+    fun is_mainnet_succeed_test() {
+        assertTrue { ZcashNetwork.Mainnet.isMainnet() }
+    }
+
+    @Test
+    fun is_mainnet_fail_test() {
+        assertFalse { ZcashNetwork.Testnet.isMainnet() }
+    }
+
+    @Test
+    fun is_testnet_succeed_test() {
+        assertTrue { ZcashNetwork.Testnet.isTestnet() }
+    }
+
+    @Test
+    fun is_testnet_fail_test() {
+        assertFalse { ZcashNetwork.Mainnet.isTestnet() }
+    }
+}
diff --git a/settings.gradle.kts b/settings.gradle.kts
index af130448..7792523f 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -110,6 +110,7 @@ dependencyResolutionManagement {
             val kotlinVersion = extra["KOTLIN_VERSION"].toString()
             val kotlinxCoroutinesVersion = extra["KOTLINX_COROUTINES_VERSION"].toString()
             val kotlinxDateTimeVersion = extra["KOTLINX_DATETIME_VERSION"].toString()
+            val kotlinxImmutableCollectionsVersion = extra["KOTLINX_IMMUTABLE_COLLECTIONS_VERSION"].toString()
             val mockitoKotlinVersion = extra["MOCKITO_KOTLIN_VERSION"].toString()
             val mockitoVersion = extra["MOCKITO_VERSION"].toString()
             val protocVersion = extra["PROTOC_VERSION"].toString()
@@ -167,6 +168,7 @@ dependencyResolutionManagement {
             library("kotlinx-coroutines-android", "org.jetbrains.kotlinx:kotlinx-coroutines-android:$kotlinxCoroutinesVersion")
             library("kotlinx-coroutines-core", "org.jetbrains.kotlinx:kotlinx-coroutines-core:$kotlinxCoroutinesVersion")
             library("kotlinx-datetime", "org.jetbrains.kotlinx:kotlinx-datetime:$kotlinxDateTimeVersion")
+            library("kotlinx-immutable", "org.jetbrains.kotlinx:kotlinx-collections-immutable:$kotlinxImmutableCollectionsVersion")
             library("material", "com.google.android.material:material:$googleMaterialVersion")
             library("zcashwalletplgn", "com.github.zcash:zcash-android-wallet-plugins:$zcashWalletPluginVersion")