canirequire › ESM-only › css-what
Is css-what ESM-only? Can you require() it?
a CSS selector parser
Last verified Sep 9, 2026 against css-what@8.0.0. JSON
ESM-only ESM-only since 8.0.0 — last CommonJS version is 7.0.0
css-what dropped its CommonJS build in 8.0.0 (March 2026). The last version you can require() on every Node.js version, including 18 and older, is 7.0.0, published Jun 29, 2025.
On Node.js 20.19+, 22.12+ and every newer release, require("css-what") works anyway: Node can load synchronous ES modules through require(). Verified on Node 20, 22, 24, 26. Node.js 18 and older still fail with ERR_REQUIRE_ESM.
css-what@8.0.0 declares engines ">=20.19.0", so Node.js 18 is outside its supported range regardless of module format.
Does css-what@8.0.0 actually load? Runtime test results
Installed and executed on Sep 9, 2026 with require("css-what") from a CommonJS file and import "css-what" from an ES module.
| Runtime | require("css-what") | import "css-what" |
|---|---|---|
| Node.js 18 | ✗ failsERR_REQUIRE_ESM | ✓ 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 css-what
ES modules (import)
import cssWhat from "css-what";CommonJS (require)
// Node.js 20.19+ / 22.12+ / newer (package has no top-level await):
const cssWhat = require("css-what");
// Any Node.js version:
const cssWhat = await import("css-what");
// Or pin the last CommonJS release:
// npm install css-what@7.0.0Module format by version
Derived from the type, main and exports fields of every stable release on npm (29 versions; the newest 29 shown).
| Versions | Format | First published |
|---|---|---|
| 8.0.0 | ESM-only | Mar 17, 2026 |
| 7.0.0 | Dual (CommonJS + ESM) | Jun 29, 2025 |
| 6.2.2 | CommonJS | Jun 28, 2025 |
| 6.2.0 – 6.2.1 | Dual (CommonJS + ESM) | Jun 28, 2025 |
| 1.0.0 – 6.1.0 | CommonJS | Feb 3, 2015 |
Frequently asked
Is css-what ESM-only?
css-what@8.0.0 is ESM-only. css-what dropped its CommonJS build in 8.0.0 (March 2026). The last version you can require() on every Node.js version, including 18 and older, is 7.0.0, published Jun 29, 2025.
Which version of css-what still supports CommonJS / require()?
7.0.0 is the last version of css-what with a CommonJS build. Install it with "npm install css-what@7.0.0". Every version from 8.0.0 on is ESM-only.
How do I use css-what from a CommonJS file?
Use a dynamic import: const mod = await import("css-what"). On Node.js 20.19+, 22.12+ and newer, a plain require("css-what") also works for ESM packages that do not use top-level await. Alternatively pin css-what@7.0.0.
Does css-what work in Bun?
Yes. import "css-what" loaded successfully in Bun 1.4 on Sep 9, 2026.
Does css-what ship TypeScript types?
Yes. css-what bundles its own type declarations; no @types package is needed.
Links
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