Show HN: I vibed a better OCaml parser than Jane Street in 69 steps
yevbar Friday, February 20, 2026
*for some cases
Using cloud sandboxes to run them in I tested: - A single coding agent just told to make a better parser - An agent told to write a better parser within the constraints of tests/benchmarks - An agent swarm that self-improved the premise with extra tests/benchmarks in order to more "truly" write a better parser
The results were a success! I was able to end up with both performance (up to 3.07× faster) and memory (up to 5.75× less) in locally runnable benchmarks.
Summary
The article discusses parsexp, a library for parsing s-expressions in Haskell. It provides a simple and efficient way to work with s-expressions, a common data format used in functional programming languages.
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Summary
github.com