Rune

Rune is a GPU-rendered, keyboard-driven IDE for power users, developed by Unstable Build. It combines code editing, terminals, command-line tools, language intelligence, debugging, file and workspace management, and AI agents in a composable multi-workspace environment with a character-grid interface. Rune Agent is provided separately as an extension in the same repository rather than being part of the core editor. Rune is an application written in Go and built with standard Go tooling; its GPU renderer uses cgo and requires platform-specific graphics and development libraries. The application is licensed under the GNU General Public License version 3 or later, while the separate rune-go-sdk extension module is licensed under Apache-2.0.

GPUI Kit is an open-source Rust framework for building cross-platform desktop applications with GPUI. It provides a single dependency that re-exports the matching GPUI release, base infrastructure, styled components, and assets. Its architecture separates gpui-base for unstyled behavior, state, and infrastructure; gpui-component for the complete styled UI system; and gpui-shell for JavaScript extensions hosted by a Rust application. The project includes more than 75 documented components and primitives, data tables, virtual lists, a code editor, dock layouts, Markdown and HTML rendering, syntax highlighting, and charts. Applications can target macOS, Windows, Linux, and WebAssembly. The interaction layer includes AccessKit accessibility support, while its UI integration tests render components in headless windows and exercise pointer and keyboard input while checking state, focus, layout, and accessibility. The repository includes a component showcase and standalone examples, including dock layouts, editors, Markdown, and HTML rendering. Software source and code examples are licensed under Apache-2.0; specified documentation prose and illustrations are also offered under CC BY 4.0.

Falco is a tiny browser engine written from scratch in Rust. It parses HTML, applies CSS, executes JavaScript in a custom virtual machine with a baseline JIT compiler, loads images, computes layout, and paints the result to a canvas that can be exported as PNG or displayed in a live interactive window. Its rendering pipeline runs from HTML through the DOM, style and layout trees, paint commands, and a canvas; the interactive mode supports scrolling, link navigation, form filling, and browsing history. The project includes its own HTML and CSS parsers, layout engine, SVG renderer, image loader, PNG encoder, WebAssembly interpreter, networking layer, and JavaScript DOM bindings, rather than wrapping WebKit, Gecko, or Chromium.

Raven is an open-source, multithreaded GUI library in C for building editors and tools. It uses a Vulkan renderer, native windows on Windows, Linux and macOS, and an XML-based interface model that applications load and connect to code written in C, C++, Rust, Python, Go, C#, Zig, LuaJIT and other supported languages. Interfaces can also be created through the C API, and changes to watched XML and theme files can be reflected while an application is running. The library provides Slate-style layouts, docking panels, a syntax-highlighting text editor, dialogs, file browsing, node graphs, timelines, color pickers, Markdown labels, themes, translations, accessibility support, touch and pen input, and solid, clear, frosted and tinted glass materials. It includes the raven_designer visual interface editor, raven_theme_editor, an inspector, examples and language bindings. Raven has an application-controlled frame loop, a render thread and job system, runtime-loaded Vulkan, native Win32, X11, Wayland and Cocoa backends, and CMake-based builds. It is distributed under the Apache License 2.0, with no royalties or paid edition stated by the project; the README notes that the public API is still subject to change.

Native Shell is an open-source, Rust-based cross-platform UI framework for iOS, Android, macOS, Windows, Linux, terminals, GPUI apps and the web. Applications can be written in Rust, TSX with Tailwind classes, or a combination of both; NSH shares components, state, APIs and a reactive layout engine while rendering through platform-specific backends such as UIKit, Android views, AppKit, Win32, GTK, ratatui or HTML. It supports standalone applications, static websites and embedding inside existing native applications. NSH can deliver TSX screens at runtime as signed packages, including plugins, feature modules and AI-generated interfaces. Host applications configure the capabilities available to these modules, which run in a sandbox. The project also provides hot updates for TSX, generated TypeScript declarations, headless tracing and an `nsh` CLI for creating, running, building and packaging applications across its supported targets. The repository is licensed under Apache License 2.0. Documentation, guides and live demos are provided at nsh.dev.