Bun v1.3.9 Release: Parallel Script Execution and Performance Improvements
By
tosh
3mo ago· 6 min readenNews
100/100
Golden Brown
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Kettled twice. Extra chewy, extra trustworthy.
Score100TypenewsSentimentpositive
Summary
Bun v1.3.9 introduces significant improvements to the JavaScript runtime, including new features for running multiple package.json scripts concurrently or sequentially with Foreman-style prefixed output. The update adds --parallel and --sequential flags to bun run, allowing developers to execute scripts across workspace packages with colored, labeled output for easy identification. The release also includes performance enhancements for Bun.markdown, RegExp operations, string methods, ESM bytecode compilation, and fixes for 23 issues.
Key quotes
· 5 pulledRun multiple package.json scripts concurrently or sequentially with Foreman-style prefixed output.
Each line of output is prefixed with a colored, padded label so you can tell which script produced it.
--parallel starts all scripts immediately with interleaved, prefixed output. --sequential runs scripts one at a time in order.
Fixes 23 issues (addressing 13 👍). Run multiple scripts in --parallel or --sequential.
Faster Bun.markdown. Faster RegExp, String.prototype.trim, String.prototype.startsWith.
Fixes 23 issues (addressing 13 👍). Run multiple scripts in --parallel or --sequential. bun:test mock & spyOn get Symbol.dispose support. ESM bytecode compilation. Faster Bun.markdown. Faster RegExp, String.prototype.trim, String.prototype.startsWith.
