Commercial impact
Case studies
Sanitized write-ups of 5 years on a multi-country healthcare SaaS (EMR) — the problem, the technical decisions, and the outcome. No proprietary code.
Testing & quality
QA transformation: Pest migration + AI-assisted E2E
Modernized a mature PHP codebase
Integrations
Payments & third-party integrations
MercadoPago QR payments, multi-country electronic invoicing, and RIS/LIS bridges — idempotency and signature verification treated as defaults.
Performance
Performance & reliability under load
Cut a critical database query from 30s to ~2s, hardened a corrupted-cache path, and ran 100+ production hotfixes with disciplined, reversible changes.