SIMD-accelerated base64 encoder/decoder with runtime CPU feature dispatch. It lives in its own small Rust crate with no runtime coupling to Bun internals, so an engineer can extract it into any project needing high-throughput base64 conversion; the SIMD lane-handling logic is non-obvious and rarely implemented correctly from scratch.

Self-contained Rust implementation of the rapidhash keyed non-cryptographic hash function (with SIMD paths), isolated in its own crate. Reusable as-is for hash tables, bloom filters, or content-addressing in any Rust project; demonstrates sophisticated instruction-level hashing craft.

A near-complete CSS 3 parser, printer, and minifier written in Rust. It handles nesting, media/container queries, custom properties, calc()/color values, and automatic vendor-prefix generation, with its own thiserror-based error model. The crate boundary is clean enough that it could be extracted as a standalone CSS toolchain for other bundlers or formatters.

A POSIX-style shell lexer/parser that produces a typed AST without executing anything. It backs Bun.shell but is an independent crate with no runtime dependencies; any tool that needs to parse shell scripts for linting, formatting, or static analysis can lift it directly.

A self-contained TypeScript implementation of the Myers diff algorithm used to render human-readable deep-equality assertion failures. It imports nothing from the Bun runtime and is a canonical, well-understood algorithmic component that any JS/TS test framework or diffing utility can reuse verbatim.

Core HTTP vocabulary types — methods, encodings, fetch modes/redirects, content-length parsing, plus a generated MIME-type table with fast lookup. It is a focused crate with its own error types and no Bun-runtime coupling beyond the shared thiserror/ErrName convention; usable by any HTTP client or server library.