Tamagui is a bunch of libraries for building UIs that share code across React and React Native.

Maestro is the easiest way to automate UI testing for your mobile app.

Turn any datasource into an internal app in minutes. Appsmith lets you drag-and-drop UI components to build pages, connect to any API, database or GraphQL source and write logic with JavaScript objects.

Tauri is a framework for building tiny, blazing fast binaries for all major desktop platforms. Developers can integrate any front-end framework that compiles to HTML, JS and CSS for building their user interface. The backend of the application is a rust-sourced binary with an API that the front-end can interact with.

Svelte is a radical new approach to building user interfaces. Whereas traditional frameworks like React and Vue do the bulk of their work in the browser, Svelte shifts that work into a compile step that happens when you build your app.

Instead of using techniques like virtual DOM diffing, Svelte writes code that surgically updates the DOM when the state of your app changes.

BackstopJS automates visual regression testing of your responsive web UI by comparing DOM screenshots over time.

Flutter is Google’s mobile UI framework for crafting high-quality native interfaces on iOS and Android in record time. Flutter works with existing code, is used by developers and organizations around the world, and is free and open source.

Fractal is a tool to help you build and document web component libraries, and then integrate them into your projects.

Component (or pattern) libraries are a way of designing and building websites in a modular fashion, breaking up the UI into small, reusable chunks that can then later be assembled in a variety of ways to build anything from larger components right up to whole pages.

Fractal helps you assemble, preview and document website component libraries, and then integrate them into your web sites, apps and build processes to create joined up, ‘living’ projects.

Fractal can be run from the command line or integrated into your project via its API.

UI toolkit for building desktop apps with Electron.

A JavaScript library for building user interfaces

Mockingbird is an online tool that makes it easy for you to create, link together, preview, and share mockups of your website or application.