---
title: Migrate from Oxlint
description: Move from standalone Oxlint to Ultracite so speed-focused projects gain shared presets, editor defaults, and a cleaner rollout path.
---

If you're already using Oxlint and want to switch to Ultracite's preconfigured setup, this guide will help you migrate while preserving your code quality standards.

## Why Migrate to Ultracite?

- **Zero Configuration**: Ultracite provides a highly configured preset of rules
- **Editor Integration**: Built-in support for AI-powered editors (Cursor, Windsurf, GitHub Copilot)
- **Consistent Workflow**: Standardized setup across projects and teams
- **Additional Tooling**: Optional Git hooks, lint-staged integration
- **Maintained Rules**: Regular updates with new best practices

## Before You Start

Make sure you have:

- An existing project using Oxlint
- Node.js 20.19+ (or 22.13+ on Node 22)
- An Oxlint configuration file (`.oxlintrc.json`, `oxlint.config.ts`, or `oxlint.config.mts`)

## Migration Options

### Option 1: Quick Migration (Recommended)

The fastest way is to run the [automatic setup script](/docs/setup#installation).

```package-install
npx ultracite init
```

When prompted, select **Oxlint** as your linting provider (it's preselected when init finds your Oxlint config). This will:

- Install Ultracite, Oxlint, and Oxfmt as dependencies
- Add Ultracite's presets to your existing `oxlint.config.ts` or `oxlint.config.mts`, keeping your own imports, extra `extends` entries, `rules`, `overrides`, `ignorePatterns`, `jsPlugins`, `settings`, and comments
- Move the rules and options from an `.oxlintrc.json`, `.oxfmtrc.json`, or `.oxfmtrc.jsonc` into the TypeScript configs and delete the JSON files (Oxlint and Oxfmt refuse to run with two configs in one directory)
- Create or update an `oxfmt.config.ts` (or `.mts`) that builds on Ultracite's formatting preset, keeping your own options
- Update your `.vscode/settings.json` in place, keeping your settings and comments (if you set up a VS Code-based editor)
- Enable `strictNullChecks` in your `tsconfig.json` files, unless it's already on (directly or through `extends`) or explicitly set to `false`, which init leaves alone with a warning
- Set up editor integrations

New configs are named `.ts` in an ES module package (`"type": "module"` in `package.json`) and `.mts` otherwise, since Node only loads ES module syntax from a `.ts` file in an ES module package. `init` never changes `"type"`. An existing config keeps its name, except a `.ts` config in a `"commonjs"` package, which is renamed to `.mts`.

If a config can't be parsed, init leaves it unchanged and warns; if it doesn't export a config object init can update, it's replaced with the Ultracite config and a warning names the file. An `.oxlintrc.json` that extends other files by path gets a warning listing them, so you can import them yourself.

After migrating, you may want to review your Oxlint config to remove any overrides that are now handled by Ultracite's preset.

### Option 2: Manual Migration

If you prefer more control over the process, create an `oxlint.config.ts` (or `oxlint.config.mts` if your `package.json` doesn't set `"type": "module"`) that extends Ultracite, and move over anything you need from `.oxlintrc.json` before deleting it:

```ts title="oxlint.config.ts"
import { defineConfig } from "oxlint";

import core from "ultracite/oxlint/core";

export default defineConfig({
  extends: [core],
  ignorePatterns: core.ignorePatterns,
});
```

Then create an `oxfmt.config.ts` (or `.mts`) that imports Ultracite's formatting preset:

```ts title="oxfmt.config.ts"
import { defineConfig } from "oxfmt";
import ultracite from "ultracite/oxfmt";

export default defineConfig({
  ...ultracite,
});
```

After the migration, restart your editor to ensure the new configuration is applied.