What’s this Udon thing anyways?

VRChat Udon is a programming language built completely in-house by the VRChat Development Team. It is designed to be secure, performant, and easy to use via the VRChat Udon Node Graph, a built-in visual programming interface that uses nodes and wires (we call them “noodles”) to connect flow, inputs, and outputs. You can build complex behaviors with Udon-- far more complex and easier to understand than unwieldy chains of Triggers and Actions.

Not only can you replicate the full behavior of Triggers and Actions with VRChat Udon, but you can create your own behaviors, sync variables with others, interact with scenes, interact with players, and more.

In addition, Udon runs in both the VRChat client and the Unity Editor, allowing you to test and debug your creations with ease.

For the more technically inclined: VRChat Udon is a VM running bytecode compiled from Udon Assembly. You can generate Udon Assembly using the built-in VRChat Udon Node Graph UI, writing your own Udon Assembly, or even by writing your own compiler to generate Udon Assembly or bytecode programs directly.

Current Udon Status

Udon is currently in OPEN ALPHA. What does that mean?

Open

You are free to share essentially everything about Udon! Post about it, stream it, make videos, etc. However, we would appreciate a few things when you’re sharing Udon:

1. When applicable to the platform you’re on, use the #MadeWithUdon hashtag to share your work!
2. When sharing VRChat Udon creations, ensure that you inform your viewers/readers that Udon is still in alpha and some things may not be working completely just yet. This isn’t the final state of Udon.
3. When someone wants to try Udon, don’t send them files, send them to our "Getting Started with Udon" thread!!

Alpha

Udon is not feature-complete, it has bugs, and therefore is considered in an Alpha state. We’ve got a lot to do. In particular, Udon Sync is not fully complete yet, which means that syncing variables and state isn’t working perfectly yet. This also affects things in the SDK that require syncing. Read the Known Issues section below for more info.

Okay, let me use it!

For now, basically all of the information you need to get started with Udon is available on our "Ask" forums. We will be updating our documentation with Udon information as time goes on in this section.

Notably, we will not be documenting Unity functions in Udon in this documentation. You should refer to Unity's documentation when applicable-- the little "help" icon on the node in the Udon Node Graph editor is very useful!

The best place to start is our "Getting Started with Udon" thread!