Post · Sep 26, 2026
Two requests read the same row, both do their maths, both write back. One of them silently disappears. How the system should resolve that isn't one answer: it depends on whether the write is a delta, a quick piece of logic, or a human edit made minutes after the read.
Post · Sep 12, 2026
A missing tenant filter is a data leak, not a crash. Row-level security fixes that structurally, but rate limits, connection pools, and error codes built for one instance break the same quiet way once the API runs as several.
Post · Sep 11, 2026
A plain payment endpoint looks correct until you trace what a double-click, a timed-out request, or a redelivered webhook actually does to it. Each one turns one payment into two. Idempotency keys are the fix, at two layers most write-ups skip.
Post · Mar 17, 2026
AI can speed up delivery, but engineers still own architecture, quality, and decisions. A simple workflow to ship faster without outsourcing judgment.
Snippet · Sep 1, 2026
A `Result<T, E>` union plus `tryCatch` wrappers that turn a throwing call into a value the caller has to inspect: the failure path becomes part of the return type instead of an invisible jump.
Cheatsheet · Sep 1, 2026
A client that retries a POST after a timeout can create the resource twice or charge a card twice. An idempotency key lets the server spot the retry and replay the first response instead of doing the work again.