What a Go Engineer Learns Building Their First Real Python Service

I spent the last three years writing Go. At NPCI I built payment systems where the wrong defaults cost real money. At ShopUp I work on backend services that have to be right, fast, and observable in that order.

This weekend I built my first real Python service: an idempotent task queue with a Postgres-backed worker, retries, dead-letter queue, full Prometheus observability, and a 16-test suite. From mkdir to GitHub release in eight hours.

I want to write about what surprised me. Some of it was the language. Most of it wasn't.

What I built

The repo is here. The short version: an HTTP API that accepts tasks with an Idempotency-Key header (Stripe style), persists them to Postgres, and a separate async worker process that picks them up using SELECT ... FOR UPDATE SKIP LOCKED, runs them, and writes the outcome back.