Capy — Create cross-platform apps in Zig

Effortlessly get a native experience across all platforms.

Simple application demonstrating Capy UI


Capy uses Zig's cross-compilation abilities in order to create an UI toolkit that runs on all major operating systems. There's no more hassle with different dev environments, you can compile from everywhere to anywhere.

Capy already works on Windows, Linux and Web. macOS and Android are work in progress. Only the iOS backend has not yet started but is planned.

OpenStreetMap viewer made with Capy UI, running with GTK+
Calculator made with Capy UI, running on Windows 10


Capy apps always have a true native look and feel on every platform. Your users won't have to bother with small behaviour differences compared to other apps. This makes a huge difference when discovering a software.

Native components

Capy always uses native UIs. This mean the user interfaces you make will always have the native look and feel of the target platform. When compiled for Windows, it looks like a Windows app. When compiled for Linux, it looks like a Linux app, and so on.

This provides OS-grade support for keyboard shortcuts, IME, accessibility. This ensures that even them obscure keyboard shortcuts from KDE to Windows still work.

Balls made with Capy UI, running with GTK+

Your Language

Capy is made possible by Zig, featuring top-notch speeds and seamless cross-compilation. Most importantly, Capy exports a C API that can be used from any language (C, C++, Node / Bun, ...)

Example Zig code, see examples/ folder in Capy source code

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