ESLint integration for code quality

Keep extension code quality predictable before issues reach runtime. ESLint runs outside the build pipeline. Run it from your scripts or continuous integration (CI).

When ESLint is a good fit

You want consistent code standards across team contributions.
You need CI checks that catch common JS/TS mistakes early.
You are enforcing extension-specific quality rules before release.

ESLint capabilities

Capability	What it gives you
JavaScript and TypeScript linting	Catch common mistakes and enforce project standards
Flat config support	Use modern `eslint.config.mjs` in new projects
CI-friendly execution	Run lint checks in local scripts and pull request pipelines
Extension-specific rulesets	Add browser-extension plugins/rules when your team needs stricter checks

Template examples

ESLint configuration template

Preconfigured lint setup you can use immediately.

npx extension@latest create my-extension --template=new-config-eslint

pnpx extension@latest create my-extension --template=new-config-eslint

yarn dlx extension@latest create my-extension --template=new-config-eslint

bunx extension@latest create my-extension --template=new-config-eslint

deno run -A npm:extension@latest create my-extension --template=new-config-eslint

Repository: examples/new-config-eslint

Usage with an existing extension

Install the core packages:

npm install -D eslint @eslint/js globals typescript-eslint

pnpm add -D eslint @eslint/js globals typescript-eslint

yarn add -D eslint @eslint/js globals typescript-eslint

bun add -d eslint @eslint/js globals typescript-eslint

deno add -D npm:eslint npm:@eslint/js npm:globals npm:typescript-eslint

Create eslint.config.mjs:

import globals from "globals";
import pluginJs from "@eslint/js";
import tseslint from "typescript-eslint";

export default [
  { files: ["**/*.{js,mjs,cjs,ts,tsx,jsx}"] },
  {
    languageOptions: {
      globals: globals.browser,
    },
  },
  pluginJs.configs.recommended,
  ...tseslint.configs.recommended,
];

Run lint commands from your scripts:

npm run lint

pnpm lint

yarn lint

bun run lint

deno task lint

If no script exists yet, run:

npx eslint .

pnpm exec eslint .

yarn eslint .

bunx eslint .

deno run -A npm:eslint .

Best practices

Keep lint rules in source control and apply them in CI.
Use lint-staged or pre-commit hooks for faster local feedback.
Add framework-specific plugins (for example, React) only when needed.

Next steps

Integrate Prettier to avoid formatting-rule conflicts.
Add Stylelint for stylesheet linting.

Introduction

Browser extension fundamentals

Getting started

Compare and migrate

Commands reference

Features

Browsers

Languages and frameworks

Integrations

Workflows

Publish to the stores

Debugging

Implementation guide

Community

ESLint integration for code quality

When ESLint is a good fit

ESLint capabilities

Template examples

ESLint configuration template

Usage with an existing extension

Best practices

Next steps

​When ESLint is a good fit

​ESLint capabilities

​Template examples

​ESLint configuration template

​Usage with an existing extension

​Best practices

​Next steps

When ESLint is a good fit

ESLint capabilities

Template examples

ESLint configuration template

Usage with an existing extension

Best practices

Next steps