ReScript Struct is a library for runtime validation that you can use to safely decode and encode JSON data.
In the new V5 release, it got a huge API redesign, making it much more convenient to use. You can see the whole list of changes in the release notes.
ReScript struct V5 became 50% faster. It’s back to first place in terms of performance 
Compared to other libs on the leaderboard, it doesn’t use code-gen and can be used in JS/TS without a compiler.
Also, it’s smaller than Zod and doesn’t blow up the bundle size like code-gen tools.
For the ones who love spoilers, there’s an opt-in ppx support in master, being polished for the next release.