Senior Software Engineer building resilient financial infrastructure. Currently at Deel Local Payroll, where I build integrations between payroll systems and tax authorities across multiple jurisdictions.
I specialise in payments engineering, distributed systems, and turning hard-won production experience into open-source tools and technical writing.
I authored a 4-part series on payments engineering and open-sourced companion implementations for each article:
| Project | What it does |
|---|---|
| settlement-reconciler | Three-way reconciliation engine matching internal records against gateway and settlement files |
| payment-state-machine | Event-sourced state machine modelling the complete payment lifecycle |
| payment-provider-health-check | Health monitoring and intelligent routing for payment provider integrations |
| idempotency-guard | Distributed idempotency middleware for payment APIs (claim-then-process pattern) |
| Project | What it does |
|---|---|
| BranchGuard | GitHub App for programmable branch protection rules via YAML configuration |
| SwaggerDiff.AspNetCore | In-app OpenAPI diff viewer and snapshot CLI for ASP.NET Core APIs |
| observability-stack | Production-ready Grafana + OpenTelemetry observability platform |
| quorum | Lightweight Approval (maker-checker/four eyes principle) Engine |
I write about payments engineering, distributed systems, and infrastructure on my blog. Recent articles:
- The Map is Not the Territory — Why payment system documentation and production reality diverge
- From Debugging to Design — Mental models for understanding any payment flow
- Building for the 1% — Engineering exception handling as first-class work
- The FinTech Staff Engineer — Translating business risk into technical architecture
- BranchGuard — Stateless GitHub automation for smarter branch rules
- Auto-Logging — Automating away "please turn on debug logs"
Read more at olawalelawal.dev
- Deel Local Payroll — Senior Software Engineer. Payroll-tax authority integrations across multiple jurisdictions including HMRC.
- Consonant Technologies (Grip) — Founding Engineer. Built a unified financial transaction layer routing payments across different financial providers.
- Innovantics (3B Platform) — Re-architected an award-winning biometric banking platform deployed across all UBA branches, processing 3B+ transactions.
- Kuda Technologies — Designed gamified rewards and referral systems at Africa's fastest-growing digital bank.
- Featured in Business Insider Africa (Leaders section) and TechCabal.