We build our TypeScript SDK code generator on Zod. So data coming from the user or API is validated and transform using generated Zod schemas. It's a fantastic

We build our TypeScript SDK code generator on Zod. So data coming from the user or API is validated and transform using generated Zod schemas. It's a fantastic library with some caveats specifically with Zod v3: - Yes, it doesn't tree-shake well because of the chaining API. We accept this tradeoff because there's a lot of value coming from those kilobytes. - In pure benchmarking numbers, it's nowhere near the fastest validator but I would wondering where you're using Zod and needing millions of operations per second. In my world, the network absolutely diminishes any performance benefits of the fastest validation library. - It can slow down typescript type checking in extreme cases. This one is aimed at those folks that have a large number of very complex schemas. A good majority will not encounter this problem. I say all this but on the flip side, I will pick Zod again and again because it has the biggest community behind and is well on its way to having ecosystem around e.g. with react-hook-form, trpc and other framework integrations. For most of my projects the trade-offs above don't materialize. Regarding all the performance and bundle size concerns, I've spoken to Colin, creator of Zod, on a couple of occasions about these and they're all getting addressed in Zod v4 which I'm raring to try out when it's available.