A SaaS that gates Bun runtime upgrades by running your test suite against each new release and blocking unsafe versions in CI

Bun's Anthropic-owned core was rewritten from Zig to Rust (960,000 lines) in a merge that shipped May 14, 2026, achieving 99.8% but not 100% test parity and containing over 10,400 unsafe Rust code blocks. Downstream projects relying on Bun's Zig binding API (Electrobun and others) began breaking immediately. The developer community voted with 708 HN points and 789 comments that this is serious: merging an LLM-assisted runtime rewrite at that scale onto a production JavaScript runtime without a safety gate is reckless. Teams running Bun in production cannot safely auto-upgrade because each release may regress their specific usage, yet staying pinned to old versions means missing security fixes. No Bun-specific upgrade gating tool exists.