target, module and moduleResolution

What Each Option Controls

Option	Controls	Typical values
`target`	which JavaScript syntax is emitted (older targets down-level `?.`, classes, async)	`ES2022` for Node 18+, `ES2017` for old browsers
`lib`	which built-in APIs are known (`Array.prototype.at`, DOM)	`["ES2023", "DOM", "DOM.Iterable"]`
`module`	the module format emitted (`require` or `import`)	`commonjs`, `esnext`, `nodenext`, `preserve`
`moduleResolution`	how `import "x"` is found on disk	`bundler`, `nodenext`, `node10`

Recommended Configs

Node.js

A modern Node.js service:

tsconfig.json

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "nodenext",
    "moduleResolution": "nodenext",
    "strict": true,
    "outDir": "dist",
    "rootDir": "src",
    "sourceMap": true,
    "skipLibCheck": true
  },
  "include": ["src"]
}

Next.js

A Next.js / Vite app (the bundler emits the JavaScript, TypeScript only checks):

tsconfig.json

{
  "compilerOptions": {
    "target": "ES2017",
    "lib": ["dom", "dom.iterable", "esnext"],
    "module": "esnext",
    "moduleResolution": "bundler",
    "jsx": "preserve",
    "noEmit": true,
    "isolatedModules": true,
    "strict": true,
    "paths": { "@/*": ["./src/*"] }
  }
}

lib Matters

Example

Object.groupBy was added in ES2024. With lib set to ES2023 (as here), TypeScript says it does not exist (TS2550, with a hint to change lib), even if your Node version has it. The second error follows from the first: the callback parameter could not be typed.

const orders = [{ city: "Pune", total: 500 }, { city: "Delhi", total: 900 }];
const byCity = Object.groupBy(orders, (o) => o.city);

Compiler output (tsc)

Line 2: error TS2550: Property 'groupBy' does not exist on type 'ObjectConstructor'. Do you need to change your target library? Try changing the 'lib' compiler option to 'es2024' or later.
Line 2: error TS7006: Parameter 'o' implicitly has an 'any' type.