Fintech2025

Northwind Pay

Cut p95 write latency from 1.4s to 180ms across the ledger.

Placeholder cover photograph for the Northwind Pay project

Stack: Go · Postgres · Kafka
Duration: 14 weeks
Year: 2025
Sector: Fintech

The problem

Settlement writes contended on a single table and blocked reconciliation nightly.

What we built

An append-only ledger with per-account partitioning and a replay-safe reconciler.

What it measured

Cut p95 write latency from 1.4s to 180ms across the ledger.

Talk to the people who would do the work.

Bring the system you already have. We will tell you where we would start, what we would leave alone, and how long the first release takes.