Bun Runtime Rewritten in Rust: 99.8% Test Suite Pass Rate Achieved on Linux x64
By
Jarred Sumner
22d ago· 2 min readenNews
75/100
Toasty
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A second-rack bagel that's nearly first-rack. Tasty stuff.
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Summary
Jarred Sumner, creator of the Bun JavaScript runtime, announces that 99.8% of Bun's test suite passes on Linux x64 glibc after a rewrite from Zig to Rust. The rewrite leverages Rust's type system for better memory safety, lifetime enforcement, and destructors, while making unsafe code more visible. Sumner cites fatigue from dealing with memory leaks, crashes, and stability issues as the primary motivation. A detailed blog post with benchmarks and memory usage data is forthcoming.
Key quotes
· 5 pulled99.8% of bun's pre-existing test suite passes on Linux x64 glibc in the rust rewrite
I am so tired of worrying about & spending lots of time fixing memory leaks and crashes and stability issues
it would be so nice if the language provided more powerful tools for preventing these things
the ugly parts look uglier (unsafe) which encourages refactoring
there will be a blog post about this. on what this means for bun, benchmarks, memory usage
99.8% of bun’s pre-existing test suite passes on Linux x64 glibc in the rust rewrite
