Hi, I'm Ayhan Sipahi.

I'm a senior tech lead in Berlin. I write here about designing and delivering software systems that stay reliable as the product grows.

Most of my work is TypeScript and AWS: application code, CDK infrastructure, and how the two fit together.

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Berlin, Germany · CET

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One Public Surface: Server Components, Passkeys, and a WebView Shell November 4, 2026

React Server Components on Lambda Web Functions as the one surface clients call: team-owned services behind token propagation, server-side passkeys, and a WebView shell.

React Server Components on Lambda Web Functions November 3, 2026

A React Router RSC app on Lambda Web Functions behind CloudFront: the entry shim, NODE_ENV, streaming, request-scoped state, partial rendering, and the origin hop.

Serverless Framework to CDK: Should You Consolidate Lambdas First? November 3, 2026

Consolidating Lambdas into a Hono Lambdalith before a Serverless Framework to CDK move roughly doubles the modeled effort. When it pays, and the pitfalls.

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

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Eco-Fleet ApS

A B2B cargo management platform, from zero to production: event-driven serverless backend on AWS, web and mobile apps, CDK infrastructure.

TypeScript · React · React Native · AWS CDK · EventBridge · DynamoDB

2025 – present

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Get in touch

~/Hi, I'm Ayhan Sipahi.

Latest posts and notes

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Hi, I'm Ayhan Sipahi.