Bun's crashes largely came from mixing garbage-collected memory with manually-managed memory, a combination so uncommon that no language is really designed to handle it safely, which is why he grew tired of Bun's bugfix list and worried about crashes.

Jarred Sumner explains that Bun's persistent crash bugs stemmed from an unusual mix of GC and manual memory management that no language, including Zig, is really built to handle. ✦ AI generated

Jarred Sumner · Simon Willison's Weblog · 2026-07-08 · original ↗

Our bugfix list felt bad and I was tired of going to sleep worrying about crashes in Bun. I don't blame Zig for that - other users of Zig don't have the bugs we had, and mixing GC with manually-managed memory is an uncommon enough thing for software to need that no language really designs for it.

Read full article ↗excerpt · fair-use quotation