Fahri KafalıFahri Kafalı — full-stack developer building end-to-end web apps and AI/LLM systems with Next.js, Node.js, PostgreSQL and Python.https://fahrikafali.com/enHello, world — and why I built this sitehttps://fahrikafali.com/blog/hello-world/https://fahrikafali.com/blog/hello-world/A short intro to who I am, what I work on, and what I plan to write about here.Tue, 30 Jun 2026 00:00:00 GMTmetaintroRepository ve Service katmanlarıyla temiz mimarihttps://fahrikafali.com/tr/blog/temiz-mimari-repository-service/https://fahrikafali.com/tr/blog/temiz-mimari-repository-service/Dayframe’i kurarken kullandığım repository/service ayrımının pratikte ne işe yaradığını anlatıyorum.Sun, 28 Jun 2026 00:00:00 GMTmimaritypescriptbackendWhat bank and payment integrations taught me about resiliencehttps://fahrikafali.com/blog/payment-integration-war-stories/https://fahrikafali.com/blog/payment-integration-war-stories/Idempotency, webhooks you can trust, and why “the happy path” is the smallest part of a payment flow.Sat, 20 Jun 2026 00:00:00 GMTbackendpaymentsnode.jsThree PostgreSQL traps that quietly slow down full-stack appshttps://fahrikafali.com/blog/postgres-performance-traps/https://fahrikafali.com/blog/postgres-performance-traps/N+1 queries, missing indexes on the columns you actually filter by, and counting the wrong way.Fri, 12 Jun 2026 00:00:00 GMTbackendpostgresqlperformanceDış sistemlere açtığım API’lerde uyduğum birkaç kuralhttps://fahrikafali.com/tr/blog/rest-api-tasarimi-notlar/https://fahrikafali.com/tr/blog/rest-api-tasarimi-notlar/Tutarlı hata formatı, versiyonlama ve “istemciyi düşün” yaklaşımı — ERP ve panel entegrasyonlarından notlar.Fri, 05 Jun 2026 00:00:00 GMTbackendapinode.jsRAG sistemleri kurarken işe yarayan pratik notlarhttps://fahrikafali.com/tr/blog/rag-pratik-notlar/https://fahrikafali.com/tr/blog/rag-pratik-notlar/Vektör arama, bağlam yönetimi ve LLM çıktısını dizginlemek — stajda ve sonrasında öğrendiklerim.Thu, 28 May 2026 00:00:00 GMTairagllmDocker for small teams: the parts that actually pay offhttps://fahrikafali.com/blog/docker-small-teams/https://fahrikafali.com/blog/docker-small-teams/Not microservices and Kubernetes — just reproducible environments and a deploy you can trust.Wed, 20 May 2026 00:00:00 GMTdevopsdockerbackendJWT ile oturum yönetimi: sık yapılan hatalarhttps://fahrikafali.com/tr/blog/jwt-oturum-yonetimi/https://fahrikafali.com/tr/blog/jwt-oturum-yonetimi/Token’ı nerede saklamalı, neyi içine koymamalı ve “çıkış yap” butonu neden zor bir problem.Tue, 12 May 2026 00:00:00 GMTbackendauthgüvenlik