What does "type": "module" mean in package.json?

Direct answer

"type": "module" treats .js files in that package as ES modules — import/export allowed, require absent unless .cjs; omitting type or "commonjs" keeps .js as CommonJS; use .mjs/.cjs to override per file.

The type field sets the default module system for .js files in a package boundary — critical in monorepos where apps/api and apps/web may differ from legacy CJS tools.

Setting	.js behavior	Extension override
"type": "module"	ESM — import/export	.cjs → CommonJS
"type": "commonjs" or omitted	CJS — require	.mjs → ESM
No type in root package.json	Node default: CommonJS for .js	Per-package in workspaces

Node version — ESM stable without flags in modern Node LTS; check engines in package.json.
Tooling — tsx/ts-node respect type; Jest/Vitest need ESM config when type is module.
Dual packages — libraries may ship "exports" map with import and require conditions.

package.json

{
  "name": "@acedevhub/api",
  "type": "module",
  "engines": { "node": ">=20" },
  "scripts": {
    "content:import:interviews": "tsx --env-file=.env src/scripts/import-content-interviews.ts"
  }
}