Engineering proofs

We shipped it
before we sold it.

Before asking any wallet team to trust this architecture, we built a full non-custodial wallet with it — and open sourced every line. Coin is the proof the on-chain OTA verification primitive works in production. Audit it. Fork it. Integrate the same pattern into your wallet.

Reference implementation

Coin — the architecture, shipped.

01 In development

Coin

The first non-custodial wallet with on-chain verified OTA updates.

We built Coin to prove the architecture ships — not just in a blog post. Local key generation, Rust transaction signing, direct RPC broadcast to chain. Before any update runs, the Rust verifier hashes the downloaded bundle with keccak256 and queries the OTARegistry contract. Hash not found on-chain → update rejected silently. No prompt, no exception, no way around it. The full source is open. Read every line before you integrate the same primitive into your wallet.

  • Non-custodial
  • Rust
  • keccak256
  • On-chain OTA
  • Tauri 2
  • Open Source

Reference implementation — OTA verification

See Coin →
Velm