# Is sisteransi ESM-only? Can you require() it?

> sisteransi@2.0.0 is ESM-only. ESM-only since 2.0.0 — last CommonJS version is 1.0.5.

ANSI escape codes for some terminal swag

Last verified Sep 9, 2026 against sisteransi@2.0.0.

sisteransi dropped its CommonJS build in 2.0.0 (June 2026). The last version with a plain require()-able CommonJS entry is 1.0.5, published Mar 18, 2020.

On Node.js 20.19+, 22.12+ and newer, require("sisteransi") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26. Node.js 18 has no require(esm), and sisteransi@2.0.0 declares Node.js >=20, so 18 is outside its supported range anyway.

sisteransi@2.0.0 declares engines ">=20", so Node.js 18 is outside its supported range regardless of module format.

## What to do

1. On Node.js 20.19+, 22.12+ and newer, require("sisteransi") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26.
2. From a CommonJS file, use a dynamic import inside an async function: const sisteransi = await import("sisteransi"). That works on every Node.js version the package supports (>=20).
3. If you need a synchronous require() or run Node.js 18: npm install sisteransi@1.0.5, the last CommonJS release (published Mar 18, 2020).
4. sisteransi@2.0.0 declares engines ">=20", so Node.js 18 is unsupported regardless: upgrade Node.js or pin an older release.
5. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 2.0.0 (Jun 25, 2026)
- Module format: ESM-only
- Last CommonJS version: 1.0.5
- ESM-only since: 2.0.0 (Jun 25, 2026)
- TypeScript types: bundled
- Node engines: >=20
- Weekly downloads: 48.4M
- License: MIT

## Runtime test results for sisteransi@2.0.0

Installed and executed on Sep 9, 2026 with require("sisteransi") from a CommonJS file and import "sisteransi" from an ES module.

| Runtime | require("sisteransi") | import "sisteransi" |
|---|---|---|
| Node.js 18 | fails (ERR_REQUIRE_ESM) | works |
| Node.js 20 | works | works |
| Node.js 22 | works | works |
| Node.js 24 | works | works |
| Node.js 26 | works | works |
| Bun 1.4.0 | works | works |

## How to import sisteransi

ES modules:

```js
import * as sisteransi from "sisteransi";
```

Namespace import shown because the ESM entry may have no default export; use named imports for what it exports.

CommonJS:

```js
// Node.js 20.19+, 22.12+ and newer (verified):
const sisteransi = require("sisteransi");

// Any Node.js version the package supports (>=20), from an async function:
async function main() {
  const sisteransi = await import("sisteransi");
}

// Or pin the last CommonJS release:
// npm install sisteransi@1.0.5
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (10 versions; the newest 10 shown).

| Versions | Format | First published |
|---|---|---|
| 2.0.0 | ESM-only | Jun 25, 2026 |
| 0.0.0 – 1.0.5 | CommonJS | Feb 20, 2018 |

## Frequently asked

**Is sisteransi ESM-only?**

sisteransi@2.0.0 is ESM-only. sisteransi dropped its CommonJS build in 2.0.0 (June 2026). The last version with a plain require()-able CommonJS entry is 1.0.5, published Mar 18, 2020.

**Which version of sisteransi still supports CommonJS / require()?**

1.0.5 is the last version of sisteransi with a CommonJS build. Install it with "npm install sisteransi@1.0.5". Every version from 2.0.0 on is ESM-only.

**How do I use sisteransi from a CommonJS file?**

From a CommonJS file, use a dynamic import inside an async function: const sisteransi = await import("sisteransi"). That works on every Node.js version the package supports (>=20). On Node.js 20.19+, 22.12+ and newer, require("sisteransi") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26. Alternatively pin sisteransi@1.0.5.

**Does sisteransi work in Bun?**

Yes. import "sisteransi" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does sisteransi ship TypeScript types?**

Yes. sisteransi bundles its own type declarations; no @types package is needed.

## Links

- [sisteransi on npm](https://www.npmjs.com/package/sisteransi)
- [Source repository](https://github.com/terkelg/sisteransi)
- [HTML version](https://canirequire.com/package/sisteransi/)
- [JSON version](https://canirequire.com/package/sisteransi.json)

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