An 82-byte fuzz_btree_v2 crash input from 2026-09-20 was left untracked in fuzz/artifacts. Replayed today it runs cleanly: the depth cap and record budget added to B-tree v2 traversal that day fixed it. It is now in the committed fuzz corpus, and a robustness test replays the fuzz target's exact code path on it so a regression fails CI rather than waiting for someone to run the fuzzer. Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>