Open source. Open possibilities.

Helsinki Design System (HDS) is an open-source design system from the City of Helsinki, offering accessible React components, CSS styles and design tokens, alongside documentation and design resources.

Material Design for Bootstrap is a free UI kit offering 700+ components, themes, and templates for building responsive, mobile-first websites. Available for jQuery, Angular, React, and Vue under MIT license.

Bootstrap is a widely used open-source front-end framework for building responsive, mobile-first websites. It provides compiled and source CSS, JavaScript components, utility classes, and theming tools, with options for install via npm, Composer, NuGet and more.

A collection of 120 plain-text DESIGN.md brand design specifications reverse engineered from live production sites, letting AI coding agents generate on-brand UI. Each brand includes real colors, typography, components and guardrails plus a self-contained preview.html.

Tailwind CSS is an open-source utility-first CSS framework for rapidly building custom user interfaces. The repository points to tailwindcss.com for full documentation, GitHub Discussions for community help and ideas, and contributing docs for pull requests.

A professional front-end starter template for building fast, robust, and adaptable websites or web apps, refined over a decade by a large community.

ZeroWeb is an experimental cross-platform browser project written in Rust, providing both the embeddable ZeroWebView library and the full ZeroBrowser application. It features a self-developed core for DOM, CSS, layout, rendering, script runtime, storage, and security, serving as an AI-driven engineering experiment.

Simple Multi Apps - Kotlin is an open-source Android application featuring a modular collection of tools including a stopwatch, games, PDF reader, and video player.

TW Elements is an MIT-licensed component library for Tailwind CSS, offering 500+ interactive UI components and 117+ design blocks with dark mode support, theming options, and quick installation for personal and commercial use.

esbuild is an extremely fast JavaScript bundler for the web, built in Go. It natively supports JavaScript, CSS, TypeScript and JSX, bundles ESM and CommonJS, and offers tree shaking, minification, source maps, a local server, watch mode and plugins via CLI, JS and Go APIs.

Anime.js is a fast, lightweight JavaScript animation library with a powerful API for animating CSS properties, SVG, DOM attributes, and JavaScript objects.

Hyper is an open-source terminal emulator built on open web standards, offering an extensible, customizable command-line experience with plugins and themes.

Parcel is a zero-configuration web build tool that supports HTML, CSS, JavaScript and many asset types out of the box, with a built-in dev server, hot reloading, Rust-based compilation, caching, and automatic production optimization.

Flowbite is an open-source UI component library built on Tailwind CSS, offering interactive components like modals, dropdowns and datepickers driven by data attributes, with vanilla JS APIs, TypeScript types, RTL support and bindings for React, Vue, Svelte and Angular.

Prettier is an opinionated code formatter that parses code and reprints it with consistent rules, taking maximum line length into account and wrapping when needed. It can run in editors on save, pre-commit hooks, or CI.

Font Awesome is a widely used icon library and toolkit providing SVG, font, and CSS resources for designers and developers. Version 7 is the current release.

designlang is a Playwright-based CLI that reads a website's live DOM and extracts its design system: DTCG tokens, Tailwind config, Figma variables, shadcn theme, component anatomy, motion tokens, brand voice, WCAG contrast audits, and multi-platform emitters, plus MCP server and Chrome extension.

Transform is an open-source polyglot web converter that converts between many data and code formats in the browser. Built with Next.js, it offers per-route transformers and can be self-hosted.

A web-based gallery designed to showcase pixel art creations.

Tabler is a free, MIT-licensed HTML dashboard UI kit built on Bootstrap 5, offering ready-made layouts, components and 120+ demo pages for admin panels, dashboards and web apps, with dark mode, RTL stylesheets, Sass sources and TypeScript types.