Writing
What failed, why the tests were green anyway, and what the fix actually was. Every number here came out of a repository or a live system.
A study of 33,596 agent-written PRs found most receive no recorded review. The diff isn't what's missing — the reasoning is.
Postmortem — agent workflows
Redis and ElastiCache Serverless are not the same database. Four assumptions broke at once, and the one that took the platform down wasn't a Redis assumption at all.
Postmortem — ride-hailing platform
Cold email is regulated differently in every country, and the regimes disagree. Putting that in a wiki page produces confident guessing. Putting it in a function produces a verdict, a citation, and a diff.
Design — outbound compliance
pdfium crashes two ways: one instance per document SIGTRAPs, and concurrent calls from a single instance segfault. The fix is a global mutex, which means the parallelism has to live somewhere else.
Postmortem — document parser
Postgres row-level security turns tenant isolation from a promise the code makes into a constraint the database enforces. Then a permissive policy quietly hands one admin every tenant's rows.
Architecture — multi-tenant LMS
Three weeks of nightly backups, every one an instant failure, every one recorded and never surfaced. Found the same afternoon as a dual-WAN link that had been down long enough to stop being redundancy.
Audit — self-hosted infrastructure
A fabricated zero reads as a correct extraction. So does an accuracy score measured on the fields you matched rows by. Both make the number go up.
Design — document extraction
Six data-loss bugs in one course editor. Five were about saving. The sixth was the editor deleting content on open, and it is still open.
Audit — course editor