JustHTML is a fascinating example of vibe engineering in action
Summary
Simon Willison reviews JustHTML, a Python HTML parser built with AI assistance, highlighting its pure Python design, test coverage, and conformance to the html5lib-tests suite. He uses it as a case study in vibe engineering—where AI handles the heavy lifting of coding and testing under human design and review—and discusses the role of coding agents in producing reliable open-source software. The piece emphasizes diverse tooling, benchmarking, and the collaboration between human and machine in building production-grade libraries.