Three builds, three rulebooks
One EU group built all three. Same architecture standard, same evidence trail, different
regime each time.
DOSSIER 01 Exchange core
A trading venue outgrew its first matching engine. Fills were hard to explain after the fact.
We split ingress, risk and matching into separate deterministic services. Every order is written to an event log first. A trading day can be replayed and reconciled fill by fill.
Ingress Risk Match Ledger
- Scope
- Matching engine, risk, ledger reconciliation
- Ingress
- FIX 4.4 · REST · WebSocket
- Standards
- MiCA-ready records · GDPR
- Model
- Fixed-scope build, then dedicated team
Crypto exchange development
DOSSIER 02 Wallet & custody
A licensed VASP needed custody it could defend to an examiner. No single person may hold a key.
Signing runs on MPC (multi-party computation). Key shares sit in separate trust zones. Policy, quorum and withdrawal limits are enforced before a signature is ever requested.
Request Policy Quorum Sign
- Scope
- MPC signing, policy engine, hot/warm split
- Controls
- Quorum approval · address allow-lists
- Standards
- AML / Travel Rule · SOC 2 readiness
- Model
- Dedicated development team
Wallet & custody engineering
DOSSIER 03 Payment rails
A PSP wanted to accept crypto beside cards. Two ledgers had to agree at the end of every day.
We built one settlement ledger for both rails. On-chain and card events land in the same double-entry book. Payouts, refunds and chargebacks are handled by shared logic.
Capture Ledger Reconcile Payout
- Scope
- Gateway, settlement ledger, payout engine
- Rails
- On-chain · SEPA · card acquiring
- Standards
- PSD2 · PCI DSS readiness
- Model
- Fixed-scope build with support retainer
Payment gateway engineering