3 releases

0.0.4 Dec 14, 2020
0.0.3 Dec 9, 2020
0.0.2 Oct 22, 2020


25K SLoC


This is the repository of the SixtyFPS project.

Warning: Pre-Alpha

SixtyFPS is still in the early stages of development: APIs will change and important features are still being developed. Do not use this yet in production.

At the moment, it's possible to create user interfaces from C++, Rust, and NodeJS. These can be compiled and shown on Linux, macOS, Windows and in Web Browsers (using WebAssembly).

We aim to support the development of this project through commercial licensing and services. We would love to get feedback from potential future customers or users.

What is SixtyFPS

SixtyFPS is a toolkit to efficiently develop fluid graphical user interfaces for any display: embedded devices and desktop applications. We support multiple programming languages, such as Rust, C++ or JavaScript.

Our design goals are:

  • Lightweight: Fit into a few hundred kilobytes of RAM and require little processing power.
  • Straightforward: Programmers and designers should feel productive and be able to enjoy the design and development process. The APIs should be consistent, easy to use, and intuitive, no matter the target language. High-quality documentation should describe the APIs, teach concepts and how to use them.
  • Native: We support many different target platforms, from embedded devices, to desktops, including mobile and web. You should feel at home on each platform; both the user and the developer. The look and feel and experience should match what users expect of an application built for a specific platform.
Printer Demo Widget Gallery
Screenshot of the Printer Demo Screenshot of the Gallery Demo


An application is composed of the business logic written in Rust, C++, or JavaScript and the .60 user interface design markup, which is compiled to native code.

Architecture Overview


SixtyFPS can be used from different frontend languages. Refer to the README of these directories for reference documentation.

The docs folder contains build instructions and internal developer docs.

Supported integration languages

The .60 Language

SixtyFPS comes with a mark-up language that is specifically designed for user interfaces: It provides a powerful way to describe graphical elements, their placement and the flow of data through the different states. At the heart of it are a familar syntax to describe the hierarchy of elements and property bindings. Here's the obligatory "Hello World":

HelloWorld := Window {
    Text {
       text: "Hello, world"
       color: blue;

Check out the language reference for more details.

Examples / Demo

All examples and demos are located in the examples folder.


Contributions are welcome. To contribute, please see CONTRIBUTING.md. Due to the dual-licensing nature, contributions require agreeing to a CLA.


The software is provided under a dual licensing scheme

  • GNU GPLv3: Open source license ideal for free software.
  • Commercial SixtyFps license: more details to come.

Contact us

Github issues can be used to report public suggestions or bugs.

You can also contact us privately by sending email to info@sixtyfps.io


~298K SLoC