SignerUsing Solana Signer

How to sign messages and send transactions on Solana

If you’re not using React, use the @account-kit/signer package to create smart wallets on Solana, sign messages, sign transactions, and sponsor transaction fees.

If you’re using React, get started with Solana wallets here.

Create a Solana signer

Once you’ve authenticated users, convert the AlchemyWebSigner to a Solana compatible signer using either of these methods:

Sign Message

To sign either a string or byte array with your Solana wallet use the signMessage method. The method accepts a UInt8Array as input:

Sign Transaction

To sign a prepared transaction with your Solana wallet use the addSignature method. The following example demonstrates signing a transfer transaction:

signing-transaction-solana-signer.tsx
1import { Connection, PublicKey, SystemProgram } from "@solana/web3.js";
2
3async function signTransaction(
4  signer: SolanaSigner,
5  toAddress: string,
6  value: number,
7) {
8  const instructions = [
9    SystemProgram.transfer({
10      fromPubkey: new PublicKey(signer.address),
11      toPubkey: new PublicKey(params.transfer.toAddress),
12      lamports: params.transfer.amount,
13    }),
14  ];
15
16  // Construct transaction with the provided instructions
17  const transaction = await signer.createTransfer(instructions, connection);
18
19  // Sign the transaction using the Solana wallet
20  await signer.addSignature(transaction);
21
22  return transaction;
23}
24
25const signedTransaction = await signTransaction(signer, "<ToAddress>", 1234);
26// Broadcast the signed transaction to the network using @solana/web3.js
27const connection = new Connection(
28  "https://solana-devnet.g.alchemy.com/v2/<API_KEY>",
29);
30await connection.sendTransaction(signedTransaction);

Sponsor transaction fees

To sponsor transaction fees on Solana:

  1. Set up your sponsorship policy in the dashboard to retrieve a policy ID
  2. Add sponsorship to the preparred transaction before signing and sending
sponsored-solana-transaction-signer.tsx
1import { Connection, PublicKey, SystemProgram } from "@solana/web3.js";
2
3async function signTransaction(
4  signer: SolanaSigner,
5  toAddress: string,
6  value: number,
7) {
8  const instructions = [
9    SystemProgram.transfer({
10      fromPubkey: new PublicKey(signer.address),
11      toPubkey: new PublicKey(params.transfer.toAddress),
12      lamports: params.transfer.amount,
13    }),
14  ];
15
16  // First - add sponsorship to the preparred transaction
17  const transaction = await signer.addSponsorship(
18    instructions,
19    connection,
20    "<policyId>", // Replace with your solana sponsorship policy ID: https://dashboard.alchemy.com/services/gas-manager/configuration
21  );
22
23  // Sign the transaction using the Solana wallet
24  await signer.addSignature(transaction);
25
26  return transaction;
27}
28
29const signedTransaction = await signTransaction(signer, "<ToAddress>", 1234);
30
31// Broadcast the signed transaction to the network using @solana/web3.js
32const connection = new Connection(
33  "https://solana-devnet.g.alchemy.com/v2/<API_KEY>", // Replace with your Alchemy API key
34);
35
36await connection.sendTransaction(signedTransaction);