Finance · Series C payments firm
Event-driven payments core
We replaced a fragile monolith with an immutable ledger and orchestration layer, cutting cost per transaction by 27%.
Node.jsKafkaPostgresAWS
99.99%
uptime
Timeline
7 months
Team
8 engineers
The challenge
What was breaking
- 01One bad deploy threatened their largest merchant.
- 02Reconciliation gaps that took days to chase down.
- 03Latency spikes during peak windows.
The approach
How we tackled it
- 01Agreed on the failure modes and regulatory surface first.
- 02Built an immutable ledger with idempotent writes.
- 03Proved the design under load before a single customer moved.
The solution
What we shipped
- 01Event-driven microservices with a single source of truth.
- 02Multi-rail routing with real-time fraud decisions.
- 03Observability that pages on drift, not on disaster.
In pictures
A closer look
The results
99.99%
uptime
-27%
cost per txn
0
reconciliation gaps
8ms
fraud decision
"We used to hold our breath on launch day. Now a deploy is a non-event — which is exactly what you want when money is moving."
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