Aptos

Derive Aptos addresses and sign transactions using Dynamic embedded wallets

Overview

Aptos uses the Ed25519 elliptic curve — the same curve as Solana. You derive an Aptos address by hashing the Solana wallet’s public key with SHA3-256 and appending a scheme byte. Transactions use BCS (Binary Canonical Serialization).

Property	Value
Curve	Ed25519
Root Wallet	Solana
Address Format	0x + SHA3-256 hex (64 chars)
Hashing	SHA3-256
Serialization	BCS
Smallest Unit	Octas (1 APT = 10^8 octas)

Dependencies

npm

npm install @aptos-labs/ts-sdk @noble/hashes bs58

yarn add @aptos-labs/ts-sdk @noble/hashes bs58

pnpm add @aptos-labs/ts-sdk @noble/hashes bs58

bun add @aptos-labs/ts-sdk @noble/hashes bs58

Derive Address

Extract the Ed25519 public key from the Solana wallet address, append the single-key scheme byte (0x00), and hash with SHA3-256:

import { sha3_256 } from "@noble/hashes/sha3";
import bs58 from "bs58";

function deriveAptosAddress(solanaAddress: string): string {
  const pubkey = bs58.decode(solanaAddress);
  const payload = new Uint8Array(33);
  payload.set(pubkey, 0);
  payload[32] = 0x00; // single-key Ed25519 scheme byte
  const hash = sha3_256(payload);
  return "0x" + bytesToHex(hash);
}

Sign a Message

Sign the raw UTF-8 bytes of the message using the Solana wallet:

import { signMessage } from "@dynamic-labs-sdk/client";
import type { WalletAccount } from "@dynamic-labs-sdk/client";

async function signAptosMessage(
  message: string,
  solWallet: WalletAccount,
): Promise<string> {
  const messageBytes = new TextEncoder().encode(message);
  const result = await signMessage({
    walletAccount: solWallet,
    message: bytesToHex(messageBytes),
  });
  return result.signature;
}

Verify a Signature

Verify the Ed25519 signature against the raw message bytes:

import { ed25519 } from "@noble/curves/ed25519";

function verifyAptosSignature(
  message: string,
  signature: string,
  solanaAddress: string,
): boolean {
  const pubkey = bs58.decode(solanaAddress);
  const messageBytes = new TextEncoder().encode(message);
  const sigBytes = decodeSig(signature);
  return ed25519.verify(sigBytes, messageBytes, pubkey);
}

Check Balance

Query the APT balance using the Aptos REST API. Tries the legacy CoinStore resource first, then falls back to the Fungible Asset model used by newer accounts:

async function getAptosBalance(address: string): Promise<string> {
  const BASE = "https://fullnode.testnet.aptoslabs.com/v1";

  // Try legacy CoinStore model
  try {
    const res = await fetch(
      `${BASE}/accounts/${address}/resource/0x1::coin::CoinStore%3C0x1::aptos_coin::AptosCoin%3E`,
    );
    if (res.ok) {
      const data = await res.json();
      const octas = BigInt(data.data?.coin?.value ?? "0");
      if (octas > BigInt(0)) {
        return (Number(octas) / 1e8).toFixed(8).replace(/\.?0+$/, "");
      }
    }
  } catch {
    // fall through to FA model
  }

  // Fall back to Fungible Asset model
  try {
    const res = await fetch(`${BASE}/view`, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        function: "0x1::primary_fungible_store::balance",
        type_arguments: ["0x1::fungible_asset::Metadata"],
        arguments: [address, "0x000000000000000000000000000000000000000000000000000000000000000a"],
      }),
    });
    if (res.ok) {
      const data = await res.json();
      const octas = BigInt(data[0] ?? "0");
      return (Number(octas) / 1e8).toFixed(8).replace(/\.?0+$/, "");
    }
  } catch {
    // ignore
  }

  return "0";
}

Send a Transfer

Use the @aptos-labs/ts-sdk to build the transaction, generate the signing message, and submit with an Ed25519 authenticator:

import {
  Aptos, AptosConfig, Network, generateSigningMessageForTransaction,
  AccountAuthenticatorEd25519, Ed25519PublicKey, Ed25519Signature,
} from "@aptos-labs/ts-sdk";
import { signMessage } from "@dynamic-labs-sdk/client";
import bs58 from "bs58";

const aptos = new Aptos(new AptosConfig({ network: Network.TESTNET }));

async function sendAptosTransfer(
  recipient: string,
  amountOctas: number,
  aptosAddress: string,
  solWallet: WalletAccount,
): Promise<string> {
  const pubkeyBytes = bs58.decode(solWallet.address);

  const transaction = await aptos.transaction.build.simple({
    sender: aptosAddress,
    data: {
      function: "0x1::aptos_account::transfer",
      functionArguments: [recipient, amountOctas],
    },
  });

  const signingBytes = generateSigningMessageForTransaction(transaction);
  const signResult = await signMessage({
    walletAccount: solWallet,
    message: bytesToHex(signingBytes),
  });
  const sigBytes = decodeSig(signResult.signature);

  const authenticator = new AccountAuthenticatorEd25519(
    new Ed25519PublicKey(pubkeyBytes),
    new Ed25519Signature(bytesToHex(sigBytes)),
  );

  const { hash } = await aptos.transaction.submit.simple({
    transaction,
    senderAuthenticator: authenticator,
  });

  return hash;
}