The @abstraxn/server-signer package lets your backend create wallets, sign transactions, and execute on-chain operations — without any user-facing UI. Use it when you need:
  • Automated server-to-server transactions (payouts, treasury ops, batch minting)
  • Backend-controlled signing (no browser, no popup)
  • Custodial or semi-custodial wallet flows managed entirely in Node.js
This SDK is for server environments only. Never expose your API key or access key in frontend code.

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1. Install the SDK

npm install @abstraxn/server-signer

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2. Get Your API Key

  1. Go to https://dashboard.abstraxn.com/
  2. Log in or sign up
  3. Navigate to Apps → Create New App
  4. Go to Wallets → Add Wallet Service
  5. Click View Details and copy your API key

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3. Authenticate

Create a client and authenticate a server wallet identity: 
import { ServerSignerClient } from '@abstraxn/server-signer';

const client = new ServerSignerClient({
  apiKey: process.env.ABSTRAXN_API_KEY!,
});

const session = await client.authenticate({
  userIdentity: 'merchant-backend-user-001',
  userName: 'Merchant Backend',
  userEmail: '[email protected]',
});

console.log(session.didCreate);       // true on first run, false on subsequent calls
console.log(session.accessToken);     // JWT access token
console.log(session.accessKey);       // 64-char hex key — persist this securely!
console.log(session.targetPublicKey); // derived public key
On the first call, authenticate generates a new accessKey for you. Save it in a secrets manager — you will need it to recover the same identity later.

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4. Verify the Session

Confirm your wallet identity: 
const me = await client.whoami();
console.log(me);
// { userId: '...', organizationId: '...', walletAddress: '0x...' }

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5. Send Your First Transaction

Create a public client and send a native transfer: 
const publicClient = client.createPublicClient({
  rpcUrl: process.env.RPC_URL!,
  chainId: 137,                   // Polygon mainnet
  organizationId: session.organizationId,
  fromAddress: session.walletAddress,
});

// Prepare the transaction (adds nonce, chain ID, gas fields)
const prepared = await publicClient.prepareTransaction({
  to: '0x1111111111111111111111111111111111111111',
  value: 1_000_000_000_000_000n,  // 0.001 MATIC
});

// Sign and broadcast in one step
const txHash = await publicClient.signAndSendPreparedTransaction(
  prepared.unsignedTransaction,
);

// Wait for on-chain confirmation
const receipt = await publicClient.waitForTransactionReceipt(txHash);
console.log('Confirmed in block:', receipt.blockNumber);

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Next Steps

  • Authentication — understand the full auth model, token refresh, and access key management
  • Transactions & Signing — prepare transactions, sign messages, typed data, and raw payloads
  • Export & Security — export private keys, handle errors, and follow security best practices