Yes, we use it to validate the API responses from the backend (as well as type validation on the backend itself from any frontend POST requests), and especially on the client side, speed and bundle size is very important.
Does arktype not come with a larger bundle size than zod? That was the reason I was shying away from it at the moment, especially with the bundle size reductions with zod 4 as well
Yeah, I can't see zod really adding that much overhead in the critical latency path for all but extremely large responses. Sometimes people pick "the fastest" library without considering whether the performance is relevant for a given code path.
