5 posts
FastAPI's Depends() handles per-request wiring. dependency-injector handles everything else — configuration, singletons, factories, and a declarative container that makes your entire object graph visible in one file.
15 min readYour pool_size=5 default just met Black Friday traffic. 200 concurrent requests, 5 connections, 195 coroutines waiting on pool checkout — then timeouts cascade into a full outage. Here is how to configure connection pooling, read replicas, and circuit breakers for production traffic.
14 min readAn N+1 query that takes 50ms with 10 rows takes 5 seconds with 1000. A memory leak that grows 1MB/hour OOMs in 3 days. Here is how to profile, detect, and load test a multi-tenant Python backend before production tells you first.
14 min readWrap your database access behind a clean interface. The Repository pattern decouples business logic from SQLAlchemy, makes testing trivial, and gives you a single place to optimize queries.
8 min readasyncio.gather() is not always the answer. Here is when to parallelize database calls, when NOT to, and how to avoid the most common SQLAlchemy async session mistakes that cause subtle production bugs.
9 min read