Find out how you can build cross-platform mixed reality experiences that look great with less effort – using your Unity or C# coding skills. 

Microsoft’s premier MR development event, Mixed Reality Dev Days, is coming June 8-9th (for in-person or online attendance). Along with 2-days of live-streamed sessions, we’re kicking off a hackathon where you can get expert help building your MR projects with the soon-to-be-released Public Preview of MRTK3 for Unity or StereoKit.


Who should join the hackathon and why?

Whether you are interested in targeting HoloLens or other OpenXR-supported devices like Oculus Quest, you’ll be getting hands-on with the latest open-source, cross-platform tools. To help you get started, we’ll release learning resources and offer you access to experts throughout the submission period.

We encourage you to team-up and extend your collective coding and creative skills. Attend our Welcome event in AltspaceVR to locate potential teammates or utilize Devpost’s built-in tools to connect with other hackers.

We seek to create a respectful, friendly, fun, and inclusive experience for Mixed Reality Dev Days participants. All are welcome! Please read our Code of Conduct for more information.


Which tools can I use?

For your project to qualify for the hackathon, it must incorporate the most recent publicly-available version of one of these tools:

MRTK for development with Unity:

The Mixed Reality Toolkit for Unity is a Microsoft-maintained, Microsoft-driven, open-source project that provides a wide variety of UX building blocks for mixed reality development including the following:

  • Input system
  • UI controls
  • Hand tracking
  • Eye tracking
  • Spatial awareness
  • Boundary system
  • Profiles
  • Solvers
  • Multi-scene management
  • Diagnostic Tools
  • In-editor simulation & much more

Projects should use MRTK3 Public Preview which was released June 8, 2022. This will give you the option of a lighter-weight solution by letting you to select only the components of the toolkit that you need. New theming and databinding features, powerful new interaction systems, and an updated design language will make it even easier to update your app’s look and add polish. Plus, native OpenXR support makes it even easier to target HoloLens, Oculus Quest, Windows Mixed Reality, and future OpenXR devices.

StereoKit for development with C#

StereoKit is a code-first, open-source library for building mixed reality experiences using C# and OpenXR. It addresses some of the most common and challenging aspects of MR development including UI, inputs, interactions, physics, shaders/material systems, working with text, asset loading, and much more. You may be surprised at just how much you can accomplish in MR with just a single line of code!  Projects using StereoKit can be viewed on HoloLens 2, desktop, or any VR device with the OpenXR runtime (e.g. Oculus Quest, Windows Mixed Reality, etc.).

  • Runtime asset pipeline
  • Fast iteration times
  • Latest .NET features
  • Performance by default
  • Flatscreen MR simulator
  • Built-in MR UI + interaction system
  • Easy access to MR inputs/data


How is Microsoft involved?

Microsoft believes that the future of mixed reality is #Open, and we are committed to making mixed reality more accessible to every developer. We hope you love these tools, which represent a collaboration between Microsoft employees and the community.

In hosting this challenge, Microsoft hopes to:

  1. Get feedback on existing features and learn what functionality would be most helpful in the future.
  2. Understand the usefulness of the tools to the developer community and assess the community’s interest. 
  3. Introduce more people to mixed reality development. We can’t wait until MR is everywhere and we hope when you try it you’ll get as excited as we are.


What do I need in order to participate?

Prior experience with Unity (if your project will be built with MRTK) or C# with Visual Studio or VS Code (if your project will be built with StereoKit), would be helpful.

If you are building a project with MRTK or StereoKit, you can develop for any head mounted device that uses the OpenXR runtime, e.g. HoloLens 2, HP Reverb 2, Oculus Quest. If you don't have access to an HMD, you can develop using the HoloLens 2 Emulator, the Windows Mixed Reality Simulator, or StereoKit’s own simulation fallback for this hackathon. The projects must be deployable to a device for final judging.


What if I’m still not sure?

Please be our guest at the no-commitment Welcome Event in AltSpaceVR on June 15, 2022. You can join via VR or from your PC. Talk to contributors and MR experts, look for teammates, or just enjoy a chance to connect with others interested in mixed reality. Details & registration link are listed in the help section below. 



I’m in! Where do I start?

  1. Register* for Mixed Reality Dev Days to stay up-to-date on news related to the live streamed sessions, the hackathon, and learning resources for MRTK3 and StereoKit. Be sure to indicate that you are participating in the hackathon when prompted. 
  2. Familiarize yourself with the project and submission requirements found in the hackathon Rules.
  3. If you want to start learning now, check out the resources tab for helpful links.** 
  4. Design is a nuanced and highly important part of building a mixed reality experience. If you are new to MR, you may want to explore design concepts before getting started.
*You can register for Mixed Reality Dev Days anytime between May 11 and the end of the hackathon submission period (July 8). The live-streamed sessions take place June 8-9.
**Updated resources will be released during Mixed Reality Dev Days. We’ll communicate these updates via email so don’t miss Step 1!

How do I get help if I need it?

If you have a request or question and can’t find what you are looking for in documentation, try these resources for the appropriate toolkit:

If you’d like to talk to a human live, we'll be offering office hours sessions for you to connect with experts. 

Event type Date Time Link to join 
AltspaceVR Welcome & Networking Event 


June 15, 2022

9:00AM - 10:00AM PT

Register here

Log in to AltspaceVR to see the event listing. Event code EZW751

Office Hours Session 


June 16, 2022

9:00AM - 10:00AM PT Join via Microsoft Teams when it's time here. 
Office Hours Session 


June 21, 2022

9:00AM - 10:00AM PT 


6:00PM - 7:00PM PT

Join via Microsoft Teams when it's time: 

9 AM Session 

6 PM Session

Office Hours Session 


June 28, 2022

6:00PM - 7:00PM PT

Join via Microsoft Teams when it's time here

AltspaceVR Participant Celebration 


August 3, 2022

9:00AM - 9:45AM PT

Register here

Log in to AltspaceVR to see the event listing. Event code GQN321


Reference the Rules section for complete Project and Submission Requirements. 

What to build: 

  • Build a new mixed reality application, game, or experience prototype built with MRTK3 or StereoKit that fits within the Mixed Reality Dev Days Hackathon theme.
    • Hackathon Theme: A New Way to Solve an Old Problem
  • The project must be capable of being successfully installed and running consistently on the platform or emulator for which it is intended. 

What to Submit

  • Provide access to your working project for judging and testing.
  • Include a video (3-5 minutes) that demonstrates your project in action (hosted publicly on a video streaming platform like YouTube). Video must include an explanation of how the project was built using MRTK3 or StereoKit. 
  • A text description that explains the functionality and specific development tool features used in the project. 

Hackathon Sponsors


$17,500 in prizes

First Place

$10,000 USD

Second Place

$5,000 USD

Third Place

$2,500 USD

Devpost Achievements

Submitting to this hackathon could earn you:


Desiree Lockwood

Desiree Lockwood
Developer Enablement team at Microsoft

Jesse McCulloch

Jesse McCulloch
Mixed Reality Developer Ecosystem team at Microsoft

Nick Klingensmith

Nick Klingensmith
Microsoft, Primary maintainer of StereoKit

Grace Hsu

Grace Hsu
Mixed Reality Toolkit team at Microsoft

Hoff Hoffman

Hoff Hoffman
Mixed Reality Toolkit team at Microsoft

Finn Sinclair
Mixed Reality Toolkit team at Microsoft

Judging Criteria

  • Challenge Fit
    Assesses how well the project fit the Hackathon's theme.
  • Quality of Idea
    Indicates creativity and originality of idea.
  • Technical Execution
    Demonstrates thoughtful execution, quality user experience, and incorporation of mixed reality concepts & features of MRTK3 or StereoKit.

Questions? Email the hackathon manager

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