A production-grade, zero-configuration preset for

Ultracite is a highly opinionated preset for ESLint, Biome and Oxlint; designed to help you and your AI models write consistent and type-safe code without the hassle of configuration.

Read the docs

Terminal

$ bun x ultracite@latest init

● Detected lockfile, using bun
│
◇ Which formatters / linters do you want to use?
│ Biome
│
◇ Which frameworks are you using?
│ React, Next.js
│
◇ Which editors do you want to configure?
│ VSCode / Cursor / Windsurf
│
◇ Which agents do you want to enable?
│ Cursor, Claude Code
│
◇ Which agent hooks do you want to enable?
│ Cursor, Claude Code
│
◆ Would you like any of the following Git hooks?
│ ◻ Husky
│ ◻ Lefthook
│ ◻ Lint-staged
│ ◻ pre-commit (Python framework)

Trusted by top companies

And used by thousands of open source projects.

Zero-config by design

Hundreds of rules for your framework to optimize your JavaScript / TypeScript code, while still allowing you to customize when needed.

I'm usingon myproject

import { defineConfig } from "eslint/config";import core from "ultracite/eslint/core";import react from "ultracite/eslint/react";import next from "ultracite/eslint/next";export default defineConfig([  {    extends: [      core,      react,      next    ],  },]);

Designed for humans and AI

Ensure consistent code style and quality across all team members and AI models, eliminating debates over formatting and reducing code review friction.

Agent Integration

Add formatting rules for AI agents and run Ultracite in agent loops.

Editor configuration

Automatically generate editor-specific rule files to work with Ultracite.

Configurable spec

Zero configuration Biome configuration out of the box.

.cursor

hooks.json

rules

ultracite.mdc

.vscode

settings.json

index.tsx

layout.tsx

utils.ts

globals.css

biome.jsonc

import React from 'react';interface User {  id: number;  name: string;  email: string;}const UserCard: React.FC<{ user: User }> = ({ user }) => {  return (    <div className="p-4 border rounded-lg shadow-sm">      <h3 className="text-lg font-semibold">{user.name}</h3>      <p className="text-gray-600">{user.email}</p>    </div>  );};export default UserCard;

Problems

index.tsx

/index.tsx

React is imported but not used

It is not necessary to wrap the return statement in a div.

Generate me a new UserCard component.

Sure! I'll generate a new UserCard component for you.

Using Ultracite

I found several issues with the code. Here's a list of suggestions:

React is imported but not used. This is a common pattern in React codebases, but it's not necessary. You can destructure the import to use the React object.
It is not necessary to wrap the return statement in a div. You can return the JSX directly.
Extract types into a type definition rather than providing them inline. This will make the code more readable and maintainable.

MCP Support

Lint and format code without needing to run Ultracite locally.

Output panel

Biome uses the VS Code output panel to show problems.

Works with all your favourite agents...

Ultracite can generate rules files for all these popular IDEs and agents, so you can get the most of out of your AI integrations.

... and all your favourite editors

Ultracite can generate configuration files for all these popular editors, so you can get the most of out of your AI integrations.

Ultracite Cloud

Automated lint fixes, powered by AI

Ultracite Cloud monitors your repositories and pull requests, automatically fixing lint issues and creating PRs. When auto-fix isn't enough, AI steps in to resolve the trickier problems.

ultracitebotcommented just nowContributor

Ultracite found 3 lint issues in this pull request and automatically fixed them.

3 Issues Fixed

src/components/Button.tsx— Missing semicolon

src/utils/format.ts— Prefer const over let

src/hooks/useAuth.ts— Unused import removed

What the community is saying

Here's what some of the most innovative and forward-thinking developers in the React ecosystem have to say about Ultracite.

shadcn

@shadcn

·Follow

I’ve switched to Ultracite for most of my projects now. Can recommend.

Hayden Bleasel

@haydenbleasel

✨ I'm unbelievably excited to introduce Ultracite v5: the AI-ready formatter that helps you write and generate code faster. 🙅 Zero-config ⚡ Lightning fast 🤖 Designed for humans and AI 💪 Maximum type safety 🔗 Plays nice with others Here's the TL;DR 👇🧵

Watch on X

2:51 AM · Jun 24, 2025

·Follow

Ustedes saben lo insoportable que soy con la configuración de ESLint y eso. No digo que vaya a reemplazar mi super mega config, pero `ultracite` anda muy bien 👀

4:58 PM · Aug 12, 2025

128

Read 9 replies

@julianbenegas8

·Follow

thanks for building Ultracite @haydenbleasel, it's awesome.

7:33 PM · Oct 10, 2025

Read 1 reply

Christopher Burns

@BurnedChris

·Follow

One of the biggest lessons I learned from my first startup is to set the bar extremely high for code quality and linting from day one. If you do not, it turns into an impossible escalator you can never step off. We are big believers in ultracite.ai, and I am always Show more

11:37 AM · Sep 21, 2025

Read 5 replies

See all tweets

A production-grade, zero-configuration preset for

Trusted by top companies

Zero-config by design

Designed for humans and AI

Works with all your favourite agents...

... and all your favourite editors

Automated lint fixes, powered by AI

What the community is saying

Install in seconds. Run in milliseconds.