Breaking the WAL

SQLite released version 3.51.3 in early 2026 to fix a longstanding Write-Ahead Logging (WAL) bug that had existed since 2010 but went undetected until it caused uptime issues at Tailscale. Using Claude and Antithesis testing, the author successfully reproduced the bug in the vulnerable 3.51.2 version within 15 minutes using a simple concurrent read/write workload, and confirmed the fix worked in 3.51.3.