Building Your First Mod

Create a new project

1. Launch Modmixer
2. From the Home screen click "+ New Mod"

Once your new project opens, Modmixer starts the conversation.

Chat with Modmixer

Chat is the heart of Modmixer. Building a mod is a lot like talking to ChatGPT, except Modmixer can also write code and control RimWorld to help you build and test mods.

When you first create a mod, Modmixer will ask you "What's your mod idea?". Your answer to this can be something simple, like "Add a new type of sword to RimWorld". Modmixer will ask questions about your idea until it has enough detail to turn it into a working mod. It will usually present a plan for you to approve before moving forward. Read it carefully and check you're happy with everything before saying yes. The next step takes a few minutes, so it's better to get the plan right from the start.

Watch Modmixer build your mod

After you approve the plan, Modmixer gets to work building your mod! Usually this takes a few minutes. During this time you'll see a message in the chat every time Modmixer reads a file or writes some code. All of this is automatic and you don't need to do anything. It's ok if these messages look a bit confusing. You'll start to understand what they mean as you get more experienced with Modmixer.

Just like a person, sometimes Modmixer makes a mistake, and you'll see it try to recover. This is a normal part of the process and nothing to worry about.

Eventually Modmixer will finish, and ask if you're ready to test. When you say "yes", it will automatically launch RimWorld, with your new mod installed. It's time to test!

Test your mod

Testing is the most important part of building a mod. Modmixer can write code, it can fix bugs, it can even launch your mod in RimWorld, but it can't test it. Only you can check the mod does what it's supposed to. When you're testing you might find:

• It doesn't do exactly what you imagined
• It works but you have an idea to make it even better
• It has a bug
• RimWorld is running slower

Come back to the Modmixer chat and explain the issue or what you want to change. Just like before, Modmixer will work for a few minutes to make changes, and eventually ask you to retest.

Keep building

At this point you've built a mod with chat, tested it, and made changes. This is how you'll spend the vast majority of your time in Modmixer. As you get more experienced you'll learn how to talk to Modmixer to get even better results.

When you're ready to share your mod on the Steam Workshop, head over to Publishing Your Mod.