TS NPM Zod Starter

TS + npm Zod Starter

Use this when adding zod to a TypeScript npm project. In a monorepo, edit the workspace the user names — ask if it isn't named.

Expected Outcome

• zod is in dependencies of the target package.json.
• The Boundary Parsing Policy below is the documented convention for the project's zod usage.

Installation

npm add zod

zod ships runtime code, so it belongs in dependencies (not devDependencies). When zod is already declared, keep its current version unless the user asks for a change.

Boundary Parsing Policy

• Parse untrusted input at the boundary with z.parse / z.safeParse. Downstream code takes the parsed value as trusted and does not re-parse.
• z.infer<typeof Schema> is the single source of truth for the static type — let it stand alone instead of declaring a parallel interface or type alias.

Why: parsing at every layer doubles the work and obscures where the trust boundary actually is.

Schemas Directory

When the project has a concrete shape worth validating, add its schema under src/schemas/<name>.ts, exporting the schema, its z.infer type, and a parse(raw: unknown) wrapper used at the boundary.

When src/schemas/ already exists, defer to the project's existing convention.

Verification

• npx tsc --noEmit passes.
• zod appears under dependencies in package.json.

References

• zod docs: https://zod.dev/