solana-program-library-memo

index.js

const Web3 = ({
  Account,
  Transaction,
  TransactionInstruction,
  PublicKey,
  Connection,
} = require("@solana/web3.js"));

const testMemo = (conn, account) => {
  const instruction = new TransactionInstruction({
    keys: [],
    programId: new PublicKey("6vDzicgVeXdeFneCRF7rT1Rqur8qAAEk2d6kURhMBeoA"),
    data: Buffer.from("cztest"),
  });
  console.log("account: ", account.publicKey.toBase58());
  Web3.sendAndConfirmTransaction(
    conn,
    new Transaction().add(instruction),
    [account],
    {
      skipPreflight: true,
      commitment: "singleGossip",
    }
  )
    .then(() => {
      console.log("done");
    })
    .catch((e) => {
      console.log("error", e);
    });
};

const main = () => {
  const conn = new Connection("https://devnet.solana.com", "singleGossip");
  const account = new Account();
  const lamports = 10 * 1000000000;
  conn.requestAirdrop(account.publicKey, lamports).then(() => {
    console.log("airdrop done");
    testMemo(conn, account);
  });
};

main();