Update install guide

INSTALL.md

@@ -1,13 +1,27 @@
+## Building with Nix
+
+The recommended and most stable way to build Radiance is with [Nix](https://nixos.org/).
+This requires an existing Nix installation on your machine.
+
+    nix-build
+    ./result/bin/radiance --help
+
+However, note that the resulting binary will only run under the same Nix environment.
+
 ## Building with Go
 
-Radiance commands can be built with standard Go tooling (Go >= 1.19 is required),
-for example:
+Radiance commands can be built with standard Go 1.19 tooling.
 
-    go run go.firedancer.io/radiance/cmd/radiance
+    go run ./cmd/radiance
 
-By default, commands that require extra dependencies (e.g. RocksDB) are disabled.
+### Without Cgo
 
-### With RocksDB
+The full set of functionality requires C dependencies via Cgo.
+To create a pure-Go build use the `lite` tag.
+
+    go build -tags=lite ./cmd/radiance
+
+### With Cgo dependencies
 
 Radiance tools that require direct access to the blockstore (such as `blockstore` and `car`)
 require a working C toolchain and extra compiler arguments to link against rocksdb.
@@ -16,23 +30,46 @@ You'll need a working C compiler toolchain as well as prerequisites listed
 by [grocksdb](https://github.com/linxGnu/grocksdb#prerequisite) and
 [RocksDB itself](https://github.com/linxGnu/grocksdb#prerequisite).
 
-For RHEL/Centos/Fedora:
+**RHEL/Centos/Fedora**
 
-    dnf -y install "@Development Tools" gflags-devel snappy snappy-devel zlib zlib-devel bzip2 bzip2-devel lz4-devel libzstd-devel
+    dnf -y install "@Development Tools" cmake zlib zlib-devel bzip2 bzip2-devel lz4-devel libzstd-devel
 
-First, check out the rocksdb submodule:
+**Debian**
 
-    git submodule update --init
+    # With package manager RocksDB
+    apt install -y librocksdb-dev
 
-Then, build the rocksdb C library:
+    # With RocksDB from source
+    apt install -y build-essential cmake zlib1g-dev libbz2-dev liblz4-dev libzstd-dev
 
-    cd third_party/rocksdb
-    make -j $(nproc) static_lib
-    cd -
+**Building RocksDB**
 
-Finally, build the `radiance` command with the `rocksdb` tag:
+To build RocksDB from source, run the following commands:
 
-    export CGO_CFLAGS="-I$(pwd)/third_party/rocksdb/include"
-    export CGO_LDFLAGS="-L$(pwd)/third_party/rocksdb"
+    git clone https://github.com/facebook/rocksdb --branch v7.10.2 --depth 1
+    cd rocksdb
+    mkdir -p build && cd build
+    cmake .. \
+      -DCMAKE_BUILD_TYPE=Release \
+      -DROCKSDB_BUILD_SHARED=OFF \
+      -DWITH_GFLAGS=OFF \
+      -DWITH_BZ2=ON \
+      -DWITH_SNAPPY=OFF \
+      -DWITH_ZLIB=ON \
+      -DWITH_ZSTD=ON \
+      -DWITH_ALL_TESTS=OFF \
+      -DWITH_BENCHMARK_TOOLS=OFF \
+      -DWITH_CORE_TOOLS=OFF \
+      -DWITH_RUNTIME_DEBUG=OFF \
+      -DWITH_TESTS=OFF \
+      -DWITH_TOOLS=OFF \
+      -DWITH_TRACE_TOOLS=OFF
+    make -j
+    cd ../..
 
-    go run -tags=rocksdb go.firedancer.io/radiance/cmd/radiance
+Finally, rebuild RocksDB with the appropriate Cgo flags.
+
+    export CGO_CFLAGS="-I$(pwd)/rocksdb/include"
+    export CGO_LDFLAGS="-L$(pwd)/rocksdb/build"
+
+    go run ./cmd/radiance

README.md

@@ -6,3 +6,5 @@ Assortment of Solana protocol modules written in Go.
 Check back later unless you're ready to read and understand the code. ⚠️
 
 [![Go Reference](https://pkg.go.dev/badge/go.firedancer.io/radiance.svg)](https://pkg.go.dev/go.firedancer.io/radiance)
+
+[Installation Guide](./INSTALL.md)