Implementing a performant URL parser from scratch

on YouTube ↗22m

" summary

Reimplements Node.js URL state machine and parser, porting the original C++ design into Rust and WebAssembly and then into a pure JavaScript version released as github.com/anonrig/url-js. Codebase is ~2,000 lines, runs >800 benchmarks and 733 Web Platform Tests, achieving 99.9% spec compliance. Rust+Wasm prototype shows significant Wasm/encoding overhead; the JS parser is about 5–6x faster than an existing JS library but remains ~95–96% slower than the native C++ implementation.

AI-written summary · about

" chapters (10)

1. 0:00URL parsers and performance
2. 2:24Why URL parsers matter
3. 5:30URL parsing state machines
4. 8:19Node.js URL parser issues
5. 10:04WebAssembly vs Rust for parsing
6. 13:15JavaScript for faster parsing
7. 15:23Optimizing JavaScript code
8. 18:34Spec compliance vs performance
9. 20:21Benchmarking results
10. 21:25Conclusion

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