eslint

library10.2.1jsnpmunverified

ESLint is a powerful, pluggable tool for identifying and reporting on patterns found in ECMAScript/JavaScript code, enforcing coding standards and catching potential issues. It uses an AST-based parser and is entirely pluggable. The current stable version is v10.2.1. It follows a frequent release cadence for minor features and bug fixes, with major versions introducing breaking changes.

testing

npm install eslint

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · ESLINT

eslint

testingjavascriptv10.2.1

Install

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Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

ESLint

✓ import { ESLint } from 'eslint';

✗ const { ESLint } = require('eslint');

ESLint v9+ is designed for ESM environments. While a CJS entry point exists, it is largely deprecated, and configuration files (`eslint.config.js`) must be ESM.

This example demonstrates how to programmatically use the ESLint class to lint a string of JavaScript code with a custom configuration, reporting any found issues.

import { ESLint } from 'eslint'; async function lintCode(code: string): Promise<void> { const eslint = new ESLint({ useEslintrc: false, // Don't use .eslintrc.* files overrideConfigFile: true, // Use this config file overrideConfig: { languageOptions: { ecmaVersion: 2022, sourceType: "module", globals: { console: "readonly" } }, rules: { "no-unused-vars": "warn", "prefer-const": "error" } } }); const results = await eslint.lintText(code); console.log(`Linting results for: "${code}"`); results.forEach(result => { result.messages.forEach(message => { console.log( ` Line ${message.line}, Col ${message.column}: ${message.message} (${message.ruleId})` ); }); }); } lintCode(` var x = 1; // no-unused-vars (warn), prefer-const (error) console.log('hello'); const y = 2; `).catch(console.error);

eslint --version

Debug

Known issues

breakingESLint v10 requires Node.js v20.19.0, v22.13.0, or >=24. Older Node.js versions are not supported.

fix

Upgrade Node.js to a supported version.

affects: >=10.0.0

breakingConfiguration files (`eslint.config.js`) must be written in ESM format (`import/export` syntax). CommonJS (`require/module.exports`) is no longer supported for config files.

fix

Refactor your `eslint.config.js` to use `import` and `export` statements, for example, `export default defineConfig(...)`.

affects: >=9.0.0

breakingProgrammatic usage of ESLint, including the `ESLint` class, is primarily designed for ESM environments. While a CJS entry point may exist, it is largely deprecated and can lead to module resolution issues.

fix

Ensure your project is configured for ESM, and use `import { ESLint } from 'eslint';`.

affects: >=9.0.0

gotchaUsing `pnpm` requires specific `.npmrc` settings (`auto-install-peers=true`, `node-linker=hoisted`) to avoid dependency resolution errors related to peer dependencies.

fix

Add `auto-install-peers=true` and `node-linker=hoisted` to your `.npmrc` file and reinstall dependencies.

affects: *

gotchaIf you use ESLint's TypeScript type definitions, TypeScript 5.3 or later is required.

fix

Ensure your project's `typescript` dependency is at version 5.3 or newer.

affects: *

Errors

Common errors & fixes

ESLint: Node.js v18.x is no longer supported. Please upgrade to a supported version.

Running ESLint v10 on an unsupported Node.js version (e.g., Node.js 18).

fix

Upgrade your Node.js installation to v20.19.0, v22.13.0, or >=24.

TypeError: ESLint is not a constructor

Attempting to use `require('eslint').ESLint` in an ESM context, or incorrectly mixing CJS and ESM, or not importing it correctly.

fix

Ensure you are using `import { ESLint } from 'eslint';` in an ESM module context.

ERR_REQUIRE_ESM: Must use import to load ES Module: .../node_modules/eslint/lib/eslint/eslint.js

Attempting to `require()` an ESLint module that is ESM-only, or trying to load an `eslint.config.js` file with `require` syntax.

fix

Convert your project or specific file to use ESM `import` statements, and ensure your `eslint.config.js` is also ESM.

Error: Cannot find module '@eslint/js/configs/eslint-recommended'

Occurs with `pnpm` if peer dependencies are not correctly hoisted or automatically installed.

fix

Add `auto-install-peers=true` and `node-linker=hoisted` to your `.npmrc` file and reinstall dependencies.

TS2307: Cannot find module 'eslint' or its corresponding type declarations.

TypeScript version is too old for ESLint's type definitions, or `eslint` is not correctly installed.

fix

Update TypeScript to version 5.3 or later, or ensure `eslint` is properly installed in your `node_modules`.

Upgrade

Version history

10.2.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/eslint/eslint ↗

packagehttps://www.npmjs.com/package/eslint ↗

homepagehttps://eslint.org ↗