Tailscale says months of control-plane outages stemmed from a 16-year-old SQLite WAL-reset corruption bug

Tailscale says a string of reliability issues from late 2025 into early 2026 was caused by a deep SQLite bug that could corrupt databases during WAL reset behavior. The company spent months investigating the failures, says it now understands and has fixed the issue, and published the post to explain the outages to customers.

The incident shows how even mature, widely trusted infrastructure can hide rare edge-case failures that surface only under specific production patterns. It also reinforces a broader trend toward companies adopting simpler embedded databases while needing stronger observability and forensic tooling as those systems scale.