Backend Platform

Ledgerline: Multi-currency payments platform

An event-driven payments core that replaces a straining monolith, migrated in stages while live transactions keep flowing.

Sector: Fintech
Typical client: B2B payments provider operating across the US and EU
Typical timeline: 24 weeks
Typical team: 6 engineers, 1 architect

Ledgerline interface: Live payments overview with volume, authorisation rate and settlement status — Live payments overview with volume, authorisation rate and settlement status

Ledgerline interface: Developer console showing payment endpoints, example responses and live request logs — Developer console showing payment endpoints, example responses and live request logs

Ledgerline interface: Reconciliation queue that matches ledger entries against provider statements — Reconciliation queue that matches ledger entries against provider statements

About this project

Payment platforms often outgrow the database they started on. Peak periods create queues, finance teams cannot easily explain a single balance, and every change feels risky because live money is moving through the system.

This engagement separates ledger, routing and settlement into services connected by an event backbone. Traffic moves across gradually, with shadow runs comparing old and new behaviour before any customer depends on the new path.

Objectives

Remove the single database bottleneck limiting peak throughput
Migrate live payment flows without a maintenance window
Give finance a complete, replayable audit trail for every transaction

What’s delivered

Domain-separated services for ledger, routing and settlement
Kafka event backbone with idempotent consumers
Double-entry ledger with automated daily reconciliation
Shadow-traffic harness and gradual cutover controls
SLO dashboards, alerting and on-call runbooks

Target outcomes

4×

peak throughput headroom

99.95%

availability objective

<250ms

p95 authorisation latency

planned downtime at cutover

Technology

Go
Apache Kafka
PostgreSQL
Kubernetes
Terraform

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