OCaml Fuzz Testing with Crowbar

Core Philosophy

1. One fuzz file per module: fuzz_foo.ml tests lib/foo.ml. Keeps tests organized and discoverable.
2. Roundtrip everything: If you have encode and decode, test decode(encode(x)) = x.
3. Crash-safety first: Parsers must never crash on arbitrary input, even malformed data.
4. Boundary conditions matter: Test edge cases (0, max values, empty input, overflow).
5. State machines need transition coverage: Test all valid and invalid state transitions.

Build Configuration

Simple single-file setup (per-package)

For standalone packages, use one fuzz file per package: