Field notes · No. 004
Senior DevOps Engineer building in public. Shipped features across Local Fitness, Ghostwriter, and more — the tradeoffs behind them, and what broke.
Secret scanners catch tokens and keys. They do not catch the amounts, names, and place-encoded labels that end up in your fixtures. Here is how to find those, replace them safely, and verify the bytes you actually committed.
A subscription can vanish from a recurring-charges report simply because the bank changed how it labels the charge. The fix wasn't new logic, it was reading a canonical key that already existed.
A local MCP server turns your bank statements into tools an AI agent can call. Here is how to build one where the model gets answers, never raw account numbers.
