canirequire › CommonJS › which
Is which ESM-only? Can you require() it?
Like which(1) unix command. Find the first instance of an executable in the PATH.
Last verified Sep 9, 2026 against which@7.0.0. JSON
CommonJS CommonJS — require() works on every Node.js version
which ships CommonJS only. require("which") works everywhere. import "which" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.
Does which@7.0.0 actually load? Runtime test results
Installed and executed on Sep 9, 2026 with require("which") from a CommonJS file and import "which" from an ES module.
| Runtime | require("which") | import "which" |
|---|---|---|
| Node.js 18 | ✓ works | ✓ works |
| Node.js 20 | ✓ works | ✓ works |
| Node.js 22 | ✓ works | ✓ works |
| Node.js 24 | ✓ works | ✓ works |
| Node.js 26 | ✓ works | ✓ works |
| Bun 1.4 | ✓ works | ✓ works |
How to import which
ES modules (import)
import which from "which";Named imports from a CommonJS package only work when Node.js can statically detect them. If a named import fails, use the default import and destructure.
CommonJS (require)
const which = require("which");Module format by version
Derived from the type, main and exports fields of every stable release on npm (37 versions; the newest 37 shown).
| Versions | Format | First published |
|---|---|---|
| 1.0.0 – 7.0.0 | CommonJS | Aug 7, 2011 |
Frequently asked
Is which ESM-only?
which@7.0.0 is a CommonJS package. which ships CommonJS only. require("which") works everywhere. import "which" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.
Can I import which with ES module syntax?
Yes. import which from "which" works in Node.js and Bun because they support importing CommonJS modules. Named imports work only when Node.js can statically detect the exports.
Does which work in Bun?
Yes. import "which" loaded successfully in Bun 1.4 on Sep 9, 2026.
Does which ship TypeScript types?
Not bundled. Install the community types with "npm install -D @types/which".
Links
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