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Engineering Notes

Write-ups on messaging, databases, and debugging across production backend systems.

21 min read

Fastify vs Express: What the 4× Actually Buys You

Fastify beats Express 4.13× on an empty handler, 2.04× on a real PostgreSQL query, and 1.16× on a 27KB response. Full methodology and raw numbers.

  • Node.js
  • Fastify
  • Express
  • Performance
  • PostgreSQL
  • Benchmarking
10 min read

Transactional Outbox in NestJS: Lessons from a Geofencing Microservice

A database transaction and a Kafka publish cannot be made atomic. Here is how the outbox pattern closes that gap in a NestJS + PostgreSQL service: the table, the relay worker, and the idempotency work it forces onto every consumer.

  • Event-Driven
  • Kafka
  • NestJS
  • PostgreSQL
  • Distributed Systems