Open Source @ Progress

We develop experiences. We make UI frameworks and app development tools used by 2.1 million developers.

We’ve also embraced open source technologies. Progress maintains and contributes much to open source software, understanding that all developers and the community benefit when we work together. Here's a taste of the many things open source that we do. Come adopt, work and collaborate with us!


Kendo UI Core for jQuery

Kendo UI® Core is the open source version of Kendo UI, the comprehensive framework for building modern web and mobile apps with HTML5 and JavaScript. Kendo UI Core is a feature-rich jQuery-based UI library for cutting-edge
front-end development. This is why Kendo UI rocks:


  • Responsive everywhere

    Kendo UI widgets are responsive to any size device screen.

  • Beautiful pixel-perfect themes

    A dozen professional and easily customizable themes are built in.

  • Easy styling

    Easily theme and style UI widgets with CSS.

  • Cross browser

    Kendo UI widgets function exactly the same way in any browser.

  • Plug & Play with web technologies

    Works with a variety of modern web development front end frameworks.

  • Powerful data solutions

    Easy bindings and offline support.

  • Choice of platform/IDE

    Work on Windows/Mac with your choice of IDE/Editor.

  • Huge community

    Developer brand recognition and a large support community to fall back on.

  • Kendo UI for jQuery Developer certification

    Get bragging rights by proving what you know.

40+ UI Components
1.5K Stars

UI for Universal Windows Platform

Building UWP apps to target all Windows 10 devices from single code base? You'll want some polished performant UI controls in your arsenal. Grab Telerik UI for UWP—the entire product suite is now open source and completely free for you to use.
Elevate your UWP apps—here's how:


20+ UI Components
12+ Chart Types
50% cut in development time
  • Stop reinventing the wheel

    Complex rich UI controls for UWP apps.

  • Consistent API canvas

    Target common and device family-specific APIs.

  • Customize your way

    Control the style of UI controls through exposed APIs.

  • Must-have essentials

    Ubiquitous controls like Grid, ListView and several Input controls.

  • Data visualization done right

    Variety of Charts, Graphs and Gauges.

  • Developer friendly

    Great documentation, demos and getting started experience.

  • Unrivaled performance

    Native XAML implementations for maximum efficiency.

JustDecompile Engine

Want to look under the covers of any .NET package? That third party assembly got you curious? Want to understand how built-in code works so you can customize yours? All this calls for decompilation. Telerik® JustDecompile™ by Progress has you covered—it's free for everyone always, with an open source decompilation engine. Here's what JustDecompile can do for you:


  • Navigate easily

    Decompiled code becomes easily consumable in Tabs.

  • Visual Studio friendly

    Decompile referenced assemblies and create other projects.

  • Large assembly support

    Includes .NET 2,3.5,4,4.5,4.6,WinRT Metadata, AppX and WinMD.

  • Choose your tooling

    Export code directly from the command prompt or integrate with Windows Explorer.

  • Extensible

    Open API for everyone to create extensions.

737 Stars
10x Faster Decompilation
C# 6 Support


JustAssembly is a free utility tool, which compares two .NET assemblies and shows the differences in each assembly code line by line, so developers like you and me can easily see what was changed and avoid introducing undesired changes. It produces a diff on all compiled code, including methods, and you can easily drill-down into each change and revise it.

  • Decompile and Compare .NET Assemblies

    Compare and analyze two .NET assembly versions with a click of a button. No need to decompile first.

  • Keep Your API Changes in Check

    JustAssembly ensures that you're not introducing breaking changes into your API when releasing a new version of your product.

  • Binary Code Diff. Method Diff.

    JustAssembly produces a diff on all compiled code, including methods. Drill into a method and see what’s changed.

  • Compare Build Outputs. Save Time.

    Be efficient. Compare the output of a complex build process before it reaches users.

Check Out These Beautiful Apps

All built with OSS Progress developer tools.