Custodial
Ethereum
Polygon
BNB Chain
MetaMask
Trust Wallet
Ethereum
Polygon
BNB Chain
MetaMask
Trust Wallet
Custodial EVM accounts for wallet apps
Build a Trust-style experience on NxtGateW. Your backend holds merchant keys; end users get an address, live balances, and signed sends without you running nodes.
The challenge
Deposit payment wallets are the wrong primitive for end-user spend balances — they carry split / IPN semantics and should not hold long-lived user funds.
The solution
Use /api/v1/wallet accounts: get-or-create by external_user_id, return private_key once, then balances / sync / send with Idempotency-Key.
How it works
- POST /api/v1/wallet/accounts with external_user_id + network.
- Persist data.id + data.address; offer optional key backup on first create.
- Home: GET balances · Activity: POST sync then GET transactions.
- Send: POST estimate → POST send with Idempotency-Key → poll sends/{id}.
What you get
- Isolated from Cash App / deposit / split wallets.
- Native + registry tokens (USDC / USDT / …) per network.
- Export-key when the user leaves custody.
