Unified Payment Gateway — MVP
The idea. Give merchants one API to collect payments, whatever the method: MTN MoMo, Airtel Money, cards. The gateway hides each operator's complexity — one integration instead of five.
What I built (MVP)
- One API for initiation and capture, with a per-operator adapter (strategy pattern) so a new PSP is added without touching the core.
- Normalised webhooks + idempotency and controlled replay against unreliable callbacks.
- Consistent statuses unified across operators and a complete transaction ledger.
- Failure and refund handling with a clear state machine.
What it demonstrates. A clean, extensible aggregation architecture that absorbs operator diversity behind a stable contract — the foundation of any collection product in Africa.
Stack
NestJS · PostgreSQL · operator adapters · Webhooks · API-first
MVP — functional gateway, not deployed to production at scale.