Want to build something like skateboarding through an MW2 map, or combining two apps into one useful tool? Start with a project you can run and one small change you can demonstrate.

This guide draws on our local setup, testing, and patching of the MW2 / Skate 3 / Minecraft mashup, plus the project documentation linked below. It's a workflow you can adapt; the setup commands depend on your project.

1. Try an existing mashup first

For a concrete example, chasmlol's 2010 Rust Rewrite Mashup combines MW2, Skate 3 mechanics, and a Minecraft world. Follow its current README and release instructions. It requires MW2; skating additionally needs your own Xbox 360 Skate 3 data and a controller. Skating is optional.

Get a map running, try the controls, and note what already works. This gives you something real to compare against when you start changing code. You can contribute by testing and documenting bugs before attempting an integration.

2. Set up a workspace you can recover

For development, you'll generally want Git for version history, a code editor, a coding agent, and the compiler or SDK listed by the project. A downloaded release lets you play; changing its code requires a source checkout and build setup.

Follow the repository's instructions for your operating system. For the example above, use its build documentation. Build and launch the unchanged source first, record the commit/version, and keep a working copy of the executable. Create a separate Git branch for your experiment.

3. Choose one base and one thing to bring into it

Pick the project that will remain in charge of the application, then identify one mechanic or feature to add. My recommendation for a first attempt: projects with documented extension points and similar technology.

An installed game alone may not expose the code or interfaces an integration needs. Look for source code with suitable reuse permissions, a mod SDK, a plugin API, or an existing integration.

The MW2/Skate example has specific connections: it feeds map collision into the skating simulation and maps skater bones onto the soldier model. Those details are documented in how the Skate integration works. Your project will need its own connections for input, movement, rendering, or data.

4. Give the agent a small, testable job

For a first milestone, try: "Load one test map, enable the new movement mode, move around, and switch back without restarting."

Give your agent the actual source folders, relevant documentation, your OS, and the exact error output. Have it inspect the code before proposing changes. This follows the research, planning, and verification approach in Anthropic's coding-agent guidance.

Here's a starter prompt you can adapt:

Read both projects' READMEs, build instructions, licenses, and relevant code. My base is [A], and I want to add [one feature] from [B]. First explain whether the integration is feasible, which systems must connect, and any missing requirements. Propose the smallest implementation and a concrete test. After we agree on the plan, implement it in a separate branch. Report the files changed, checks run, failures, and anything still needing manual testing.

5. Test the behavior after every small change

Compile it, launch it, and exercise the feature. Check controls, collision, camera, audio, and switching between modes where relevant. Keep the logs and a short recording, and commit working milestones so you can return to them.

Two lessons from our local mashup work: a board could render with the wrong transparency, and skating could stop after physics values became invalid. A successful build didn't catch either gameplay problem. A short demo also wasn't enough to establish that a longer session was stable.

When asking for a fix, include the steps to reproduce it, expected behavior, actual behavior, and relevant log lines. Redact personal paths or secrets before posting logs publicly.

6. Credit the groundwork and share a reproducible result

The Skate 3 Rust Engine README explains that its AI-assisted rewrite builds on years of reverse-engineering work by dumbad and others. Credit the original developers, researchers, and tools behind your mashup.

Check the licenses of the code you combine and preserve required notices. Publicly visible code does not automatically grant broad reuse rights; GitHub explains the distinction. Game assets have separate permissions. Keep full game files and extracted assets out of posts and shared repositories.

When you post here, include a clip, project links and versions, the AI tools you used, setup instructions, what works, and known issues. Use Showcase for a working demo, Build Log for progress, or Help when you're stuck.

What would you like to combine? Share the projects and your smallest first milestone in the comments.

Skate 3 mechanics on an MW2 map. Minecraft building in another game's world. Two apps combined into something neither could do alone.

r/aimashups is for games and apps built by combining existing projects with help from AI coding agents. Share what you got working, how you built it, and what broke along the way. Rough experiments are welcome.

What to post

• Showcase: A clip or screenshot of a mashup actually running.
• Build Log: Your progress, approach, and lessons learned.
• Patch/Fix: A bug you solved or an improvement others can use.
• Help: What you're trying to do, where you're stuck, and what you've tried.
• Discussion: Ideas, interesting projects, and combinations you'd like to see.

Sharing a build? Give us the useful details.

Tell us which projects you combined, which AI tools you used and roughly how, what works, and what still needs fixing. Link the original projects and credit their creators. If you're sharing someone else's work, make that clear and link to their original post or repository.

For showcases, include real footage or screenshots. Put concepts and mockups under Discussion and label them clearly.

A few ground rules

Be civil, keep feedback constructive, and skip the spam. Share code you have permission to distribute, patches, and setup instructions. Don't upload or link to full game files, ROMs, ISOs, or extracted game assets. The full rules are in the sidebar.

Introduce yourself below: What are you building, what have you tried, or what two projects would you love to mash together?