diff --git a/depends/packages/librustzcash.mk b/depends/packages/librustzcash.mk
index b15857fa5..277d78d06 100644
--- a/depends/packages/librustzcash.mk
+++ b/depends/packages/librustzcash.mk
@@ -3,8 +3,8 @@ $(package)_version=0.1
 $(package)_download_path=https://github.com/zcash/$(package)/archive/
 $(package)_file_name=$(package)-$($(package)_git_commit).tar.gz
 $(package)_download_file=$($(package)_git_commit).tar.gz
-$(package)_sha256_hash=65363973dfbdde3bc9cb4427724db399c201f580eb42fb02b0b86e043931c90b
-$(package)_git_commit=5e220695e5961c8619a1095a3b9022509c6c9b9d
+$(package)_sha256_hash=22cd7afa38b0f60a0b326d1810f1c48204972946d3bf2d2ed6e3feb79e10d554
+$(package)_git_commit=fefa46b4c4f2815819e0c7f2d1771239596ea450
 $(package)_dependencies=rust $(rust_crates)
 $(package)_patches=cargo.config
 
diff --git a/src/gtest/test_joinsplit.cpp b/src/gtest/test_joinsplit.cpp
index c7f4577a3..0ad480574 100644
--- a/src/gtest/test_joinsplit.cpp
+++ b/src/gtest/test_joinsplit.cpp
@@ -3,6 +3,7 @@
 #include "utilstrencodings.h"
 
 #include <boost/foreach.hpp>
+#include <boost/variant/get.hpp>
 
 #include "zcash/prf.h"
 #include "util.h"
@@ -42,7 +43,7 @@ void test_full_api(ZCJoinSplit* js)
     boost::array<uint256, 2> commitments;
     uint256 rt = tree.root();
     boost::array<ZCNoteEncryption::Ciphertext, 2> ciphertexts;
-    ZCProof proof;
+    SproutProof proof;
 
     {
         boost::array<JSInput, 2> inputs = {
@@ -59,6 +60,7 @@ void test_full_api(ZCJoinSplit* js)
 
         // Perform the proof
         proof = js->prove(
+            false,
             inputs,
             outputs,
             output_notes,
@@ -75,9 +77,11 @@ void test_full_api(ZCJoinSplit* js)
         );
     }
 
+    auto sprout_proof = boost::relaxed_get<ZCProof, ZCProof, GrothProof>(&proof);
+
     // Verify the transaction:
     ASSERT_TRUE(js->verify(
-        proof,
+        *sprout_proof,
         verifier,
         pubKeyHash,
         randomSeed,
@@ -134,6 +138,7 @@ void test_full_api(ZCJoinSplit* js)
 
         // Perform the proof
         proof = js->prove(
+            false,
             inputs,
             outputs,
             output_notes,
@@ -150,9 +155,11 @@ void test_full_api(ZCJoinSplit* js)
         );
     }
 
+    sprout_proof = boost::relaxed_get<ZCProof, ZCProof, GrothProof>(&proof);
+
     // Verify the transaction:
     ASSERT_TRUE(js->verify(
-        proof,
+        *sprout_proof,
         verifier,
         pubKeyHash,
         randomSeed,
@@ -185,7 +192,8 @@ void invokeAPI(
 
     boost::array<SproutNote, 2> output_notes;
 
-    ZCProof proof = js->prove(
+    SproutProof proof = js->prove(
+        false,
         inputs,
         outputs,
         output_notes,
diff --git a/src/gtest/test_transaction.cpp b/src/gtest/test_transaction.cpp
index ee674c6e2..44c047364 100644
--- a/src/gtest/test_transaction.cpp
+++ b/src/gtest/test_transaction.cpp
@@ -43,6 +43,7 @@ TEST(Transaction, JSDescriptionRandomized) {
 
     {
         auto jsdesc = JSDescription::Randomized(
+            false,
             *params, pubKeyHash, rt,
             inputs, outputs,
             inputMap, outputMap,
@@ -59,6 +60,7 @@ TEST(Transaction, JSDescriptionRandomized) {
 
     {
         auto jsdesc = JSDescription::Randomized(
+            false,
             *params, pubKeyHash, rt,
             inputs, outputs,
             inputMap, outputMap,
@@ -72,6 +74,7 @@ TEST(Transaction, JSDescriptionRandomized) {
 
     {
         auto jsdesc = JSDescription::Randomized(
+            false,
             *params, pubKeyHash, rt,
             inputs, outputs,
             inputMap, outputMap,
diff --git a/src/primitives/transaction.cpp b/src/primitives/transaction.cpp
index a18e8f65a..a3ee0302c 100644
--- a/src/primitives/transaction.cpp
+++ b/src/primitives/transaction.cpp
@@ -9,20 +9,25 @@
 #include "tinyformat.h"
 #include "utilstrencodings.h"
 
-JSDescription::JSDescription(ZCJoinSplit& params,
-            const uint256& pubKeyHash,
-            const uint256& anchor,
-            const boost::array<libzcash::JSInput, ZC_NUM_JS_INPUTS>& inputs,
-            const boost::array<libzcash::JSOutput, ZC_NUM_JS_OUTPUTS>& outputs,
-            CAmount vpub_old,
-            CAmount vpub_new,
-            bool computeProof,
-            uint256 *esk // payment disclosure
-            ) : vpub_old(vpub_old), vpub_new(vpub_new), anchor(anchor)
+#include "librustzcash.h"
+
+JSDescription::JSDescription(
+    bool makeGrothProof,
+    ZCJoinSplit& params,
+    const uint256& pubKeyHash,
+    const uint256& anchor,
+    const boost::array<libzcash::JSInput, ZC_NUM_JS_INPUTS>& inputs,
+    const boost::array<libzcash::JSOutput, ZC_NUM_JS_OUTPUTS>& outputs,
+    CAmount vpub_old,
+    CAmount vpub_new,
+    bool computeProof,
+    uint256 *esk // payment disclosure
+) : vpub_old(vpub_old), vpub_new(vpub_new), anchor(anchor)
 {
     boost::array<libzcash::SproutNote, ZC_NUM_JS_OUTPUTS> notes;
 
     proof = params.prove(
+        makeGrothProof,
         inputs,
         outputs,
         notes,
@@ -42,19 +47,20 @@ JSDescription::JSDescription(ZCJoinSplit& params,
 }
 
 JSDescription JSDescription::Randomized(
-            ZCJoinSplit& params,
-            const uint256& pubKeyHash,
-            const uint256& anchor,
-            boost::array<libzcash::JSInput, ZC_NUM_JS_INPUTS>& inputs,
-            boost::array<libzcash::JSOutput, ZC_NUM_JS_OUTPUTS>& outputs,
-            boost::array<size_t, ZC_NUM_JS_INPUTS>& inputMap,
-            boost::array<size_t, ZC_NUM_JS_OUTPUTS>& outputMap,
-            CAmount vpub_old,
-            CAmount vpub_new,
-            bool computeProof,
-            uint256 *esk, // payment disclosure
-            std::function<int(int)> gen
-        )
+    bool makeGrothProof,
+    ZCJoinSplit& params,
+    const uint256& pubKeyHash,
+    const uint256& anchor,
+    boost::array<libzcash::JSInput, ZC_NUM_JS_INPUTS>& inputs,
+    boost::array<libzcash::JSOutput, ZC_NUM_JS_OUTPUTS>& outputs,
+    boost::array<size_t, ZC_NUM_JS_INPUTS>& inputMap,
+    boost::array<size_t, ZC_NUM_JS_OUTPUTS>& outputMap,
+    CAmount vpub_old,
+    CAmount vpub_new,
+    bool computeProof,
+    uint256 *esk, // payment disclosure
+    std::function<int(int)> gen
+)
 {
     // Randomize the order of the inputs and outputs
     inputMap = {0, 1};
@@ -66,6 +72,7 @@ JSDescription JSDescription::Randomized(
     MappedShuffle(outputs.begin(), outputMap.begin(), ZC_NUM_JS_OUTPUTS, gen);
 
     return JSDescription(
+        makeGrothProof,
         params, pubKeyHash, anchor, inputs, outputs,
         vpub_old, vpub_new, computeProof,
         esk // payment disclosure
@@ -105,7 +112,21 @@ public:
 
     bool operator()(const libzcash::GrothProof& proof) const
     {
-        return false;
+        uint256 h_sig = params.h_sig(jsdesc.randomSeed, jsdesc.nullifiers, pubKeyHash);
+
+        return librustzcash_sprout_verify(
+            proof.begin(),
+            jsdesc.anchor.begin(),
+            h_sig.begin(),
+            jsdesc.macs[0].begin(),
+            jsdesc.macs[1].begin(),
+            jsdesc.nullifiers[0].begin(),
+            jsdesc.nullifiers[1].begin(),
+            jsdesc.commitments[0].begin(),
+            jsdesc.commitments[1].begin(),
+            jsdesc.vpub_old,
+            jsdesc.vpub_new
+        );
     }
 };
 
diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
index 1066601a1..bea2485e9 100644
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -36,15 +36,6 @@ static_assert(SAPLING_TX_VERSION >= SAPLING_MIN_TX_VERSION,
 static_assert(SAPLING_TX_VERSION <= SAPLING_MAX_TX_VERSION,
     "Sapling tx version must not be higher than maximum");
 
-static constexpr size_t GROTH_PROOF_SIZE = (
-    48 + // π_A
-    96 + // π_B
-    48); // π_C
-
-namespace libzcash {
-    typedef boost::array<unsigned char, GROTH_PROOF_SIZE> GrothProof;
-}
-
 /**
  * A shielded input to a transaction. It contains data that describes a Spend transfer.
  */
@@ -246,11 +237,13 @@ public:
 
     // JoinSplit proof
     // This is a zk-SNARK which ensures that this JoinSplit is valid.
-    boost::variant<libzcash::ZCProof, libzcash::GrothProof> proof;
+    libzcash::SproutProof proof;
 
     JSDescription(): vpub_old(0), vpub_new(0) { }
 
-    JSDescription(ZCJoinSplit& params,
+    JSDescription(
+            bool makeGrothProof,
+            ZCJoinSplit& params,
             const uint256& pubKeyHash,
             const uint256& rt,
             const boost::array<libzcash::JSInput, ZC_NUM_JS_INPUTS>& inputs,
@@ -262,6 +255,7 @@ public:
     );
 
     static JSDescription Randomized(
+            bool makeGrothProof,
             ZCJoinSplit& params,
             const uint256& pubKeyHash,
             const uint256& rt,
diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp
index fa1238edc..6ca651981 100644
--- a/src/test/transaction_tests.cpp
+++ b/src/test/transaction_tests.cpp
@@ -372,7 +372,7 @@ BOOST_AUTO_TEST_CASE(test_basic_joinsplit_verification)
     auto verifier = libzcash::ProofVerifier::Strict();
 
     {
-        JSDescription jsdesc(*pzcashParams, pubKeyHash, rt, inputs, outputs, 0, 0);
+        JSDescription jsdesc(false, *pzcashParams, pubKeyHash, rt, inputs, outputs, 0, 0);
         BOOST_CHECK(jsdesc.Verify(*pzcashParams, verifier, pubKeyHash));
 
         CDataStream ss(SER_DISK, CLIENT_VERSION);
@@ -387,13 +387,13 @@ BOOST_AUTO_TEST_CASE(test_basic_joinsplit_verification)
 
     {
         // Ensure that the balance equation is working.
-        BOOST_CHECK_THROW(JSDescription(*pzcashParams, pubKeyHash, rt, inputs, outputs, 10, 0), std::invalid_argument);
-        BOOST_CHECK_THROW(JSDescription(*pzcashParams, pubKeyHash, rt, inputs, outputs, 0, 10), std::invalid_argument);
+        BOOST_CHECK_THROW(JSDescription(false, *pzcashParams, pubKeyHash, rt, inputs, outputs, 10, 0), std::invalid_argument);
+        BOOST_CHECK_THROW(JSDescription(false, *pzcashParams, pubKeyHash, rt, inputs, outputs, 0, 10), std::invalid_argument);
     }
 
     {
         // Ensure that it won't verify if the root is changed.
-        auto test = JSDescription(*pzcashParams, pubKeyHash, rt, inputs, outputs, 0, 0);
+        auto test = JSDescription(false, *pzcashParams, pubKeyHash, rt, inputs, outputs, 0, 0);
         test.anchor = GetRandHash();
         BOOST_CHECK(!test.Verify(*pzcashParams, verifier, pubKeyHash));
     }
diff --git a/src/utiltest.cpp b/src/utiltest.cpp
index 6f43afbfa..dbc92bca9 100644
--- a/src/utiltest.cpp
+++ b/src/utiltest.cpp
@@ -40,7 +40,7 @@ CWalletTx GetValidReceive(ZCJoinSplit& params,
 
     // Prepare JoinSplits
     uint256 rt;
-    JSDescription jsdesc {params, mtx.joinSplitPubKey, rt,
+    JSDescription jsdesc {false, params, mtx.joinSplitPubKey, rt,
                           inputs, outputs, 2*value, 0, false};
     mtx.vjoinsplit.push_back(jsdesc);
 
@@ -123,7 +123,7 @@ CWalletTx GetValidSpend(ZCJoinSplit& params,
 
     // Prepare JoinSplits
     uint256 rt = tree.root();
-    JSDescription jsdesc {params, mtx.joinSplitPubKey, rt,
+    JSDescription jsdesc {false, params, mtx.joinSplitPubKey, rt,
                           inputs, outputs, 0, value, false};
     mtx.vjoinsplit.push_back(jsdesc);
 
diff --git a/src/wallet/asyncrpcoperation_mergetoaddress.cpp b/src/wallet/asyncrpcoperation_mergetoaddress.cpp
index 4ea230c4f..a29527e29 100644
--- a/src/wallet/asyncrpcoperation_mergetoaddress.cpp
+++ b/src/wallet/asyncrpcoperation_mergetoaddress.cpp
@@ -768,6 +768,7 @@ UniValue AsyncRPCOperation_mergetoaddress::perform_joinsplit(
     uint256 esk; // payment disclosure - secret
 
     JSDescription jsdesc = JSDescription::Randomized(
+        mtx.fOverwintered && (mtx.nVersion >= SAPLING_TX_VERSION),
         *pzcashParams,
         joinSplitPubKey_,
         anchor,
diff --git a/src/wallet/asyncrpcoperation_sendmany.cpp b/src/wallet/asyncrpcoperation_sendmany.cpp
index 1df7bcd93..b62e64469 100644
--- a/src/wallet/asyncrpcoperation_sendmany.cpp
+++ b/src/wallet/asyncrpcoperation_sendmany.cpp
@@ -990,6 +990,7 @@ UniValue AsyncRPCOperation_sendmany::perform_joinsplit(
     uint256 esk; // payment disclosure - secret
 
     JSDescription jsdesc = JSDescription::Randomized(
+            mtx.fOverwintered && (mtx.nVersion >= SAPLING_TX_VERSION),
             *pzcashParams,
             joinSplitPubKey_,
             anchor,
diff --git a/src/wallet/asyncrpcoperation_shieldcoinbase.cpp b/src/wallet/asyncrpcoperation_shieldcoinbase.cpp
index 2cb5a7499..51e3a581c 100644
--- a/src/wallet/asyncrpcoperation_shieldcoinbase.cpp
+++ b/src/wallet/asyncrpcoperation_shieldcoinbase.cpp
@@ -359,6 +359,7 @@ UniValue AsyncRPCOperation_shieldcoinbase::perform_joinsplit(ShieldCoinbaseJSInf
     uint256 esk; // payment disclosure - secret
 
     JSDescription jsdesc = JSDescription::Randomized(
+            mtx.fOverwintered && (mtx.nVersion >= SAPLING_TX_VERSION),
             *pzcashParams,
             joinSplitPubKey_,
             anchor,
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index e372c1cf4..ddceccbeb 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -2640,7 +2640,8 @@ UniValue zc_sample_joinsplit(const UniValue& params, bool fHelp)
 
     uint256 pubKeyHash;
     uint256 anchor = ZCIncrementalMerkleTree().root();
-    JSDescription samplejoinsplit(*pzcashParams,
+    JSDescription samplejoinsplit(false,
+                                  *pzcashParams,
                                   pubKeyHash,
                                   anchor,
                                   {JSInput(), JSInput()},
@@ -2991,7 +2992,8 @@ UniValue zc_raw_joinsplit(const UniValue& params, bool fHelp)
     mtx.nVersion = 2;
     mtx.joinSplitPubKey = joinSplitPubKey;
 
-    JSDescription jsdesc(*pzcashParams,
+    JSDescription jsdesc(false,
+                         *pzcashParams,
                          joinSplitPubKey,
                          anchor,
                          {vjsin[0], vjsin[1]},
@@ -3667,7 +3669,13 @@ UniValue z_sendmany(const UniValue& params, bool fHelp)
     size_t txsize = 0;
     for (int i = 0; i < zaddrRecipients.size(); i++) {
         // TODO Check whether the recipient is a Sprout or Sapling address
-        mtx.vjoinsplit.push_back(JSDescription());
+        JSDescription jsdesc;
+
+        if (mtx.fOverwintered && (mtx.nVersion >= SAPLING_TX_VERSION)) {
+            jsdesc.proof = GrothProof();
+        }
+
+        mtx.vjoinsplit.push_back(jsdesc);
     }
     CTransaction tx(mtx);
     txsize += GetSerializeSize(tx, SER_NETWORK, tx.nVersion);
diff --git a/src/zcash/JoinSplit.cpp b/src/zcash/JoinSplit.cpp
index a503cb455..ef92d3967 100644
--- a/src/zcash/JoinSplit.cpp
+++ b/src/zcash/JoinSplit.cpp
@@ -18,6 +18,10 @@
 #include "sync.h"
 #include "amount.h"
 
+#include "librustzcash.h"
+#include "streams.h"
+#include "version.h"
+
 using namespace libsnark;
 
 namespace libzcash {
@@ -135,7 +139,8 @@ public:
         }
     }
 
-    ZCProof prove(
+    SproutProof prove(
+        bool makeGrothProof,
         const boost::array<JSInput, NumInputs>& inputs,
         const boost::array<JSOutput, NumOutputs>& outputs,
         boost::array<SproutNote, NumOutputs>& out_notes,
@@ -266,6 +271,55 @@ public:
             out_macs[i] = PRF_pk(inputs[i].key, i, h_sig);
         }
 
+        if (makeGrothProof) {
+            if (!computeProof) {
+                return GrothProof();
+            }
+
+            GrothProof proof;
+
+            CDataStream ss1(SER_NETWORK, PROTOCOL_VERSION);
+            ss1 << inputs[0].witness.path();
+            std::vector<unsigned char> auth1(ss1.begin(), ss1.end());
+
+            CDataStream ss2(SER_NETWORK, PROTOCOL_VERSION);
+            ss2 << inputs[1].witness.path();
+            std::vector<unsigned char> auth2(ss2.begin(), ss2.end());
+
+            librustzcash_sprout_prove(
+                proof.begin(),
+
+                phi.begin(),
+                rt.begin(),
+                h_sig.begin(),
+
+                inputs[0].key.begin(),
+                inputs[0].note.value(),
+                inputs[0].note.rho.begin(),
+                inputs[0].note.r.begin(),
+                auth1.data(),
+
+                inputs[1].key.begin(),
+                inputs[1].note.value(),
+                inputs[1].note.rho.begin(),
+                inputs[1].note.r.begin(),
+                auth2.data(),
+
+                out_notes[0].a_pk.begin(),
+                out_notes[0].value(),
+                out_notes[0].r.begin(),
+
+                out_notes[1].a_pk.begin(),
+                out_notes[1].value(),
+                out_notes[1].r.begin(),
+
+                vpub_old,
+                vpub_new
+            );
+
+            return proof;
+        }
+
         if (!computeProof) {
             return ZCProof();
         }
diff --git a/src/zcash/JoinSplit.hpp b/src/zcash/JoinSplit.hpp
index 03c499ff0..7b095a6e9 100644
--- a/src/zcash/JoinSplit.hpp
+++ b/src/zcash/JoinSplit.hpp
@@ -15,6 +15,14 @@
 
 namespace libzcash {
 
+static constexpr size_t GROTH_PROOF_SIZE = (
+    48 + // π_A
+    96 + // π_B
+    48); // π_C
+
+typedef boost::array<unsigned char, GROTH_PROOF_SIZE> GrothProof;
+typedef boost::variant<ZCProof, GrothProof> SproutProof;
+
 class JSInput {
 public:
     ZCIncrementalWitness witness;
@@ -59,7 +67,8 @@ public:
                          const uint256& pubKeyHash
                         );
 
-    virtual ZCProof prove(
+    virtual SproutProof prove(
+        bool makeGrothProof,
         const boost::array<JSInput, NumInputs>& inputs,
         const boost::array<JSOutput, NumOutputs>& outputs,
         boost::array<SproutNote, NumOutputs>& out_notes,
diff --git a/src/zcbenchmarks.cpp b/src/zcbenchmarks.cpp
index 9a794089c..4c60fec40 100644
--- a/src/zcbenchmarks.cpp
+++ b/src/zcbenchmarks.cpp
@@ -116,7 +116,8 @@ double benchmark_create_joinsplit()
 
     struct timeval tv_start;
     timer_start(tv_start);
-    JSDescription jsdesc(*pzcashParams,
+    JSDescription jsdesc(false, // TODO: ?
+                         *pzcashParams,
                          pubKeyHash,
                          anchor,
                          {JSInput(), JSInput()},