Introducing zshy — a bundler-free batteries-included build tool for TypeScript libraries 🐒

RT @jherr: I should really just:. alias "pnpm init"="pnpm init && pnpm add zod". At this point.

RT @yusukebe: Now, Zod OpenAPI supports Zod v4!.

wild to see the README from back then.

first commit to tRPC was five years ago today

nothing like being out on the water not thinking about zod error codes

the Cursor docs want you to migrate your codebase to Zod 4

normalize using JSON pointer syntax in docs

repo link below. there's a big FAQ in there for the real nerds 📦.

that's it! there's a lot of big wins with this approach:. 🍌 no config file, just package.json and tsconfig.json.🍌 no bundler.🍌 use any file structure you want.🍌 use any import syntax you want (.js, .ts, extensionless).

then writes your "exports" map directly into your package.json — you never have to worry about it again

it generates the following files:

then run a build with `npx zshy`. it runs two tsc builds against your specified entrypoints. ESM .ts → .js/.d.ts.CJS .ts → .cjs/.d.cts

the DX is heavily inspired by the wonderful library "tshy" by @izs. tshy really blazed the trail for tsc-first build tools. after installing `zshy`, specify your entrypoint map in package.json:

there's no bundler, just plain tsc — so you get typechecking *and* gold standard transpilation . the usual "bundler-ey" stuff (extension rewriting, asset copying, import.meta shims, etc) are implemented with the (super underutilized) TypeScript Compiler API

this started life as an internal built tool for Zod, but I'm spinning it out as a standalone tool

yeah. this feels good

if you want to learn more about this versioning approach, check out the Versioning docs . if you don’t, upgrade to zod@4 and you’ll never have to think about it agin 🙃.

Library authors—if you’ve implemented Zod 4 support according to best practices ( no code changes should be needed. Just bump your peer dependency range to include zod@4 and cut a new patch/minor. don't drop 3.25.x support (at least until your next major)