Milagro Blog

Personal notes on backend engineering, distributed systems, and the occasional side-project postmortem.

On cache invalidation in multi-region gRPC services

April 12, 2026

A long-overdue writeup on the pitfalls of stale reads across regions, and why a conservative TTL beats clever invalidation schemes nine times out of ten...

Notes from migrating a 40TB Postgres cluster

March 3, 2026

The migration took 11 weeks. The plan said 4. Here's what went wrong...

Building a lightweight feature flag system in 300 lines of Go

January 28, 2026

Every flag system starts simple and ends in tears. This one is still simple. Ask me again in six months...