Fullstack dev server Hot reloading HTML & static sites Standalone HTML CSS Loaders Single-file executable Plugins Macros Bytecode Caching Minifier esbuild

Bytecode Caching

Speed up JavaScript execution with bytecode caching in Bun's bundler

Macros

Run JavaScript functions at bundle-time with Bun macros

Minifier

Reduce bundle sizes with Bun's JavaScript and TypeScript minifier

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Usage Basic usage (CommonJS)With standalone executables ESM bytecode Combining with other optimizations Performance impact When to use bytecode Great for:CLI tools Build tools and task runners Standalone executables Skip it for:Limitations Version compatibility Source code still required Bytecode is not obfuscation Production deployment Docker CI/CD Debugging Verify bytecode is being used Common issues What is bytecode?Why lazy parsing makes this even better The bytecode format Inside a .jsc file What bytecode does NOT contain The tradeoff: file size Why is bytecode so much larger?Mitigation strategies Versioning and portability Cross-architecture portability: ✅Cross-version portability: ❌Unlinked vs. linked bytecode Unlinked bytecode (what's cached)Linked bytecode (runtime execution)