Zayd Mulani

Your database documentation says REPEATABLE READ. Your code assumes it. Have you ever checked? I spent the last stretch building adya, a black-box checker for transactional isolation. You give it a log of transactions a database ran, and it tells you which isolation guarantees held. For each one that didn't, it prints the transactions involved and the chain of reads and writes that proves the violation.

Some bugs only happen with one combination of API data, timing and local state. The failing run and a working run differ in dozens of ways, and figuring out which difference matters usually means commenting things out until something changes. Causality Cage automates that. You give it a failing session and a passing session.

Every "AI code search" tool released this year does the same thing under the hood: chunk your repo, embed every chunk, stuff the vectors into an index, and keep that index in sync every time you commit. GitLab Duo does it. Sourcegraph does it. JetBrains shipped a whole RAG pipeline for it. It works, but it means you're maintaining a second copy of your codebase that can drift out of sync with the first one, and on a repo that changes fast, "rebuild the index" becomes its own chore.