Case study
Exchange & custodial wallets
ExchangeCustodial walletsBTC/ETHFiat onrampKYC
The setting
Within a blockchain ecosystem that raised $25M, we were the team behind the money-critical parts: the exchange and the custody of user funds — where every bug is somebody's balance.
What we built
- An exchange with order books — matching, balances, and the operational tooling around them.
- Custodial BTC/ETH wallets: deposit detection, confirmation tracking, and withdrawal flows treated as state machines, not events.
- A fiat-to-crypto purchase flow with real-time KYC moderation, so compliance kept pace with signups instead of queueing them.
Where it stands
The ecosystem launched on our rails. The patterns we hardened here — ledger invariants, idempotent money paths, KYC as a state machine — are the ones we now write about in our field notes.
Rate this case study:
Building something in the same territory?