From 8b252e00a39778fe7657493733c48e3a93ccbd70 Mon Sep 17 00:00:00 2001
From: Keyur Vaitha <keyur@cypherock.com>
Date: Tue, 5 May 2026 18:59:50 +0530
Subject: [PATCH 1/2] feat: add v0 txn support for solana

---
 .../src/operations/signTxn/index.ts           | 67 ++++++++++++++-----
 1 file changed, 51 insertions(+), 16 deletions(-)

diff --git a/packages/app-solana/src/operations/signTxn/index.ts b/packages/app-solana/src/operations/signTxn/index.ts
index 7ccfb65d..6d946f4f 100644
--- a/packages/app-solana/src/operations/signTxn/index.ts
+++ b/packages/app-solana/src/operations/signTxn/index.ts
@@ -100,22 +100,57 @@ export const signTxn = async (
   let serializedTxnHex: string | undefined;
 
   if (params.serializeTxn) {
-    const solanaWeb3 = getSolanaWeb3();
-    const transaction = solanaWeb3.Transaction.populate(
-      solanaWeb3.Message.from(Buffer.from(params.txn, 'hex')),
-    );
-    if (latestBlockHash) transaction.recentBlockhash = latestBlockHash;
-    assert(
-      transaction.feePayer,
-      new Error('Cannot decode feePayer in solana txn'),
-    );
-    transaction.addSignature(
-      transaction.feePayer,
-      Buffer.from(signature, 'hex'),
-    );
-    const serializedTxnBuffer = transaction.serialize();
-    serializedTxnHex = uint8ArrayToHex(serializedTxnBuffer);
-    serializedTxn = base58Encode(serializedTxnBuffer);
+    const msgBytes = Buffer.from(params.txn, 'hex');
+    const isVersioned = msgBytes.length > 0 && msgBytes[0] === 0x80;
+
+    if (isVersioned) {
+      const updatedMsgBytes = Buffer.from(msgBytes);
+      if (latestBlockHash) {
+        const bhBytes = Buffer.from(base58Decode(latestBlockHash));
+        /* Locate blockhash in v0 message:
+         [0x80 version] [3 header bytes] [compact-u16 acct count] [acct keys * 32] [32 blockhash]
+         See: https://solana.com/docs/core/transactions/versioned-transactions */
+        let off = 4;
+        let acctCount = 0;
+        let shift = 0;
+        while (off < updatedMsgBytes.length) {
+          const b = updatedMsgBytes[off];
+          off += 1;
+          acctCount += (b % 128) * 2 ** shift;
+          if (b < 128) break;
+          shift += 7;
+        }
+        off += acctCount * 32;
+        bhBytes.copy(updatedMsgBytes, off);
+      }
+
+      const sigCount = Buffer.from([0x01]);
+      const sigBytes = Buffer.from(signature, 'hex');
+      const serializedTxnBuffer = Buffer.concat([
+        sigCount,
+        sigBytes,
+        updatedMsgBytes,
+      ]);
+      serializedTxnHex = uint8ArrayToHex(serializedTxnBuffer);
+      serializedTxn = base58Encode(serializedTxnBuffer);
+    } else {
+      const solanaWeb3 = getSolanaWeb3();
+      const transaction = solanaWeb3.Transaction.populate(
+        solanaWeb3.Message.from(msgBytes),
+      );
+      if (latestBlockHash) transaction.recentBlockhash = latestBlockHash;
+      assert(
+        transaction.feePayer,
+        new Error('Cannot decode feePayer in solana txn'),
+      );
+      transaction.addSignature(
+        transaction.feePayer,
+        Buffer.from(signature, 'hex'),
+      );
+      const serializedTxnBuffer = transaction.serialize();
+      serializedTxnHex = uint8ArrayToHex(serializedTxnBuffer);
+      serializedTxn = base58Encode(serializedTxnBuffer);
+    }
   }
 
   return {

From e8fdb82a0cbdcaf761349feb870ae10d31b041b5 Mon Sep 17 00:00:00 2001
From: Keyur Vaitha <keyur@cypherock.com>
Date: Mon, 1 Jun 2026 19:33:54 +0530
Subject: [PATCH 2/2] feat: serialize v0 txn using VersionedTransaction from
 solana web3

---
 .../src/operations/signTxn/index.ts           | 37 +++++--------------
 1 file changed, 10 insertions(+), 27 deletions(-)

diff --git a/packages/app-solana/src/operations/signTxn/index.ts b/packages/app-solana/src/operations/signTxn/index.ts
index 6d946f4f..0cb33f54 100644
--- a/packages/app-solana/src/operations/signTxn/index.ts
+++ b/packages/app-solana/src/operations/signTxn/index.ts
@@ -103,38 +103,21 @@ export const signTxn = async (
     const msgBytes = Buffer.from(params.txn, 'hex');
     const isVersioned = msgBytes.length > 0 && msgBytes[0] === 0x80;
 
+    const solanaWeb3 = getSolanaWeb3();
     if (isVersioned) {
-      const updatedMsgBytes = Buffer.from(msgBytes);
-      if (latestBlockHash) {
-        const bhBytes = Buffer.from(base58Decode(latestBlockHash));
-        /* Locate blockhash in v0 message:
-         [0x80 version] [3 header bytes] [compact-u16 acct count] [acct keys * 32] [32 blockhash]
-         See: https://solana.com/docs/core/transactions/versioned-transactions */
-        let off = 4;
-        let acctCount = 0;
-        let shift = 0;
-        while (off < updatedMsgBytes.length) {
-          const b = updatedMsgBytes[off];
-          off += 1;
-          acctCount += (b % 128) * 2 ** shift;
-          if (b < 128) break;
-          shift += 7;
-        }
-        off += acctCount * 32;
-        bhBytes.copy(updatedMsgBytes, off);
-      }
-
-      const sigCount = Buffer.from([0x01]);
-      const sigBytes = Buffer.from(signature, 'hex');
-      const serializedTxnBuffer = Buffer.concat([
-        sigCount,
-        sigBytes,
-        updatedMsgBytes,
+      const serializedVersionedTxn = Buffer.concat([
+        Buffer.from([0x01]),
+        Buffer.from(signature, 'hex'),
+        msgBytes,
       ]);
+      const vt = solanaWeb3.VersionedTransaction.deserialize(
+        serializedVersionedTxn,
+      );
+      if (latestBlockHash) vt.message.recentBlockhash = latestBlockHash;
+      const serializedTxnBuffer = Buffer.from(vt.serialize());
       serializedTxnHex = uint8ArrayToHex(serializedTxnBuffer);
       serializedTxn = base58Encode(serializedTxnBuffer);
     } else {
-      const solanaWeb3 = getSolanaWeb3();
       const transaction = solanaWeb3.Transaction.populate(
         solanaWeb3.Message.from(msgBytes),
       );