Once UI System Core
Once UI System Core is a free, open-source design system built with React and Next.js. The open-source frontend infrastructure for the AI-native web. It has 267 GitHub stars and is released under the MIT license. A live demo is linked from this page.
Get started
Copy the files into a new folder with degit (no git history), or clone the repository with git.
npx degit once-ui-system/core my-ui
cd my-ui
npm install # then run the dev script from the READMEgit clone --depth 1 https://github.com/once-ui-system/core.git my-uiSources: GitHub docs on template repositories, degit.
About Once UI System Core
The open-source frontend infrastructure for the AI-native web The indie design system for Next.js apps Learn how to set up and build with Once UI at docs.once-ui.com.
Built with
- React
- Next.js
- TypeScript
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What is Once UI System Core?
Once UI System Core is a free, open-source design system built with React and Next.js. The open-source frontend infrastructure for the AI-native web. It has 267 GitHub stars and is released under the MIT license. A live demo is linked from this page.
How do I use Once UI System Core?
Copy the files into a new folder with npx degit once-ui-system/core my-ui (no git history), or fork the repository on GitHub. Then follow the README for the install and dev commands.
Can I use Once UI System Core for commercial projects?
Yes. Once UI System Core is released under the MIT license, a permissive license that allows commercial use as long as you keep the copyright and license notice. Third-party assets bundled with it (images, fonts, icons) may have their own terms.
Is Once UI System Core maintained?
The repository's most recent commit was on Sep 25, 2026. Its latest release is v2.0.0. appsgit only lists templates from repositories with a commit in the last six months.