1. One-Key Setup ​

1.1 Download the HashNut MPC Client ​

Download the latest HashNut MPC Client for your OS and CPU architecture from the address below, then unpack it.

https://github.com/nuttybounty/hashnut-mpc-client/releases

xattr -cr ./hashnut-mpc-mainnet-darwin-arm64

If you downloaded the amd64 build, run:

xattr -cr ./hashnut-mpc-mainnet-darwin-amd64

1.2 Initialise the wallet ​

• Set a password

• Import your wallet's private key

  Import the private key into the wallet. The default chain type is evm; choose tron if it is a Tron wallet.

• Click "Import Wallet"

• Choose the wallet type

• Paste the private key and import

• Imported

• Switch to the chain you want to use

1.3 Filling in the one-key setup parameters ​

• Open the One-Key Setup page

• Fill in the parameters

  • What each parameter does:

  Parameter	Purpose
  Contract alias	A name for the split contract. After deployment you will see the contract under this name in the dashboard and in the MPC Client.
  Withdrawal address	Where funds go when you withdraw, after the money customers paid has been aggregated.
  Token	The token the receipt addresses authorise the split contract to move, usdt by default. Each receipt address grants the split contract permission to transfer this token, which is how aggregation works.
  Number of receipt addresses	How many receipt addresses to create. Start with 5; once you have verified order creation, aggregation and withdrawal, top it up to at least 50.
  notifyUrl	The URL HashNut calls with order notifications — think of it as your webhook URL.
  callbackUrl	Where the HashNut payment page redirects the user after the order is created.
  bindIp	The public IP of the server that creates orders. Leave it as * for now and bind it in the dashboard once you have finished debugging.
  Overpayment policy	What to do when a customer overpays. The default is auto-confirm: an overpaid order is treated as successful.
  Underpayment policy	Whether HashNut notifies you when a customer underpays. The default is to notify.
  Remark	A label for the API key, visible in the dashboard after setup completes.

• Estimate the fee

• Confirm

• In progress

• Finished

1.4 Save the account info ​

• The exported account info looks like this:
  text

  HashNut One-Key Setup Result
  Generated at: 2026-08-01 14:54:46
  ============================================================
  
  Chain                 ETH
  Split Contract        0xbd09...fca
  Contract Alias        demo-1
  Withdrawal Address    0x4d....ec
  Token        usdt (0xdac17f958d2ee523a2206206994597c13d831ec7)
  Receipt Addresses     5
  Deployment Transaction  0xa19....73d
  
  accessKey     01...YW
  secretKey     H1...Tt
  notifyUrl     https://.../api/notify
  callbackUrl   http://.../payment-result
  bindIp        *
  Overpayment Policy    Auto-confirm (default) (AUTO_CONFIRM)
  Underpayment Policy   Notify merchant (default) (NOTIFY)
  
  ------------------------------------------------------------
  Paste into demo-go / demo-java's migrate.sql
  ------------------------------------------------------------
  -- HashNut One-Key Setup export: ETH / demo-1
  INSERT INTO t_hashnut_api_key (block_chain, splitter, access_key_id, secret_key) VALUES
      ('ETH', '0xbd09...fca', '01...YW', 'H1...Tt')
  ON CONFLICT (block_chain) DO UPDATE SET
      splitter = EXCLUDED.splitter,
      access_key_id = EXCLUDED.access_key_id,
      secret_key = EXCLUDED.secret_key;