TypeScript

Zeno uses the @zeno-lib/typescript package to share strict TypeScript configurations across all packages and apps.

You never have to manually configure tsconfig.json options like moduleResolution, jsx, lib, strict, Next.js include globs, or the Next.js plugin — just extend one config and everything is set up correctly.

Available Configs

The configs form an inheritance chain — each level extends the previous one:

Usage

Extend the appropriate config in your package's tsconfig.json:

{
  "extends": "@zeno-lib/typescript/nextjs.json"
}

That's it. No need to configure compilerOptions, include, or exclude — the config handles module resolution, strict checks, JSX, DOM libs, and Next.js-specific includes for you.

Which Config to Use

Examples in the Repo

What's Included

Base Config

Every config inherits these sensible defaults:

• Bundler module resolution — Works with modern bundlers (Vite, Turbopack, webpack)
• ESNext modules with verbatimModuleSyntax — Clean import/export handling
• JSON imports — resolveJsonModule enabled
• Incremental builds — Faster recompilation
• Isolated modules — Compatible with SWC and esbuild
• No emit — Bundlers handle output, TypeScript only type-checks

Strictest Config

Enables all strict checks beyond strict: true:

• noFallthroughCasesInSwitch — Prevent fallthrough in switch statements
• noImplicitOverride — Require override keyword
• noImplicitReturns — All code paths must return
• noUnusedLocals — No unused local variables
• noUnusedParameters — No unused function parameters
• noUncheckedIndexedAccess — Indexed access returns T | undefined
• allowUnreachableCode: false — Error on unreachable code
• allowUnusedLabels: false — Error on unused labels

Next.js Config

On top of React support, the Next.js config automatically:

• Registers the next TypeScript plugin for App Router type safety
• Includes next-env.d.ts and .next/types/**/*.ts for generated types
• Includes all *.ts and *.tsx files in the project root

Type Checking

Run type checking across all packages:

pnpm types:check

Or for a specific package:

pnpm turbo run types:check --filter @zeno-lib/ui