I design and build digital products, custom software and scalable systems.
01 Selected writing
Three signals and the different questions they answer, the trace-ID join that delivers 80% of the value, the collector pattern, tail-based sampling that keeps the interesting 100%, and the incident-driven rollout.
Why revocation is where stateless goes to die, the XSS blast-radius problem, the specific habitats where JWTs genuinely shine, and the sessions-at-the-edge / tokens-between-machines architecture.
The unanswerable-timeout thought experiment, the implementation with its three traps disarmed, why the property must compose down the whole call chain, and the cheaper natural-key alternatives.
From both sides of hundreds of integrations: honest status codes, RFC 7807 errors with trace IDs, cursor pagination, idempotency and versioning posture, and the DX multipliers that halve support tickets.
03 Services
04 About
I'm Berkan Yılmaz — a senior full-stack developer and AI/ML & DevOps specialist based in Istanbul, building and operating large-scale, mission-critical systems since 2018: from multi-country POS platforms and banking integrations to EV-charging infrastructure and production AI.
Read moreLet's build together
Tell me about your idea, your needs or your current system — and let's shape a solution that actually ships.
