Reference build: a non-custodial wallet backend
A wallet's backend reads state, warns about risk, previews actions and sends value. This build covers all four with primitives that leave signing on your side.
The challenge
Wallet teams usually assemble a balance API, an allowance scanner, a simulator and an RPC sender separately. The goal is to source all of them from one key while keeping the wallet non-custodial.
- Balances / portfolio / net-worthC1
- Approvals / value-at-riskC2
- Simulate tx (preview)C2
- Build / sign / broadcastC2
Read balances and net-worth
Populate the wallet home from one balances call spanning BTC, ETH and TRON, with portfolio net-worth derived in the same read.
Warn on risky approvals
Scan token approvals and surface value-at-risk so users can revoke dangerous allowances before they're drained.
Preview, then send
Simulate every outgoing transaction to show the expected result and catch reverts, then build, sign and broadcast — with signing under your control.
What the build delivers
- Full wallet read/write surface from one key
- Approval risk surfaced before funds can be drained
- Non-custodial: signing never has to leave your side
Frequently asked
Does the backend ever hold keys?
Only if you opt into custodial signing. The default build keeps signing on your side.
How are reverts avoided?
Simulation previews the transaction so users don't pay for a transfer that would fail.
Top up, get a key, ship.
Self-serve. Pay in crypto or card. Metered by credits — heavy primitives cost more, simple ones are cheap.
Get API key