Available for new engagements
Hi, I'm Ayhan Sipahi.
I'm an independent software consultant in Berlin. I help product teams ship software systems that keep working after the team that built them has moved on.
Most of my work is TypeScript and AWS: application code, CDK infrastructure, and how the two fit together. The writing here comes from that work. Every post is published in English and Turkish.
Latest Posts and Notes
View All PostsBefore building an internal service layer, decide whether to. What the layer costs per call, the volume where VPC Lattice wins, and when direct invoke still beats it.
A private REST API structurally cannot carry gRPC, and every AWS surface that speaks gRPC excludes Lambda targets. What to keep from gRPC, and what to drop.
The private REST API, the resource policy that switches it on, per-route AWS_IAM grants, the two CDK stacks, and signing the call from a Node 22 Lambda.
New here? Start with Comparing TypeScript Formatting and Linting Tools: Biome, Oxlint, ESLint, and Prettier · Understanding Career Levels in Tech - From Entry to Distinguished Engineer · MCP vs Direct API Access for AI Agents: When to Skip the MCP Layer
Selected Outcomes
“In 4 months, we moved our core platform from a legacy setup to a cloud-native architecture with less operational friction.”
“With a focused AWS and serverless redesign, we reduced annual infrastructure spend by around $200K.”
How I Can Help
Focused support for architecture and delivery decisions.
Architecture Review
A focused review of your system: code, AWS infrastructure, and delivery pipeline. You get a written, prioritized set of findings and a practical technical direction.
Fixed scope · typically 1–2 weeks
Technical Advisory
Ongoing advisory for product and engineering teams: architecture decisions, delivery unblocking, and a second pair of senior eyes when it matters.
Retainer · a few hours a week
Want to work together? Get in touch.