01 · before the workshop

Setup

Welcome! Before the workshop there are three installs and one signup, about 15 minutes total. Doing it before we start means you spend the workshop building your sim instead of watching download bars. And if anything refuses to install, you have plenty of time to ask in chat and get it sorted.

What you're installing, in one line each

Python runs your sim. Git uploads your code to the internet. GitHub is where the code lives so others can see it. Antigravity is the editor with an AI agent that writes the code for you. That's the whole toolkit.

1 · Install Python

Go to python.org/downloads. Install Python 3.12 — not the newest one. Taichi (the graphics library we use) only works on Python 3.10, 3.11, or 3.12, and the big yellow download button gives you 3.13 or 3.14, which won't work with it directly. Grab the installer from the Python 3.12.10 release page — scroll to the bottom and pick the installer for your OS (Windows 64-bit or macOS). Newer 3.12 pages don't have installers anymore, so use that exact link.
Run the installer.
- Windows: tick "Add python.exe to PATH" on the first screen. Then Install.
- Mac: keep clicking Continue through the prompts. Defaults are fine.

screenshot: the python.org downloads page

The PATH checkbox matters (Windows only)

If you missed it, run the installer again and tick it. Otherwise Antigravity's terminal won't find Python.

Already installed Python 3.13 or 3.14? You're fine — don't reinstall.

There's a one-command fix. Open a terminal and run pip install uv (on Mac: pip3 install uv). That installs a tool called uv which can fetch its own private copy of Python 3.12 whenever a program needs one — your 3.14 stays untouched. Then, during the workshop, run your sim with uv run --python 3.12 --with taichi main.py instead of python main.py. Even easier: just tell the AI agent "run this with uv using Python 3.12 and taichi, my system Python is 3.14" and it handles the rest. The first run downloads Python 3.12 in the background (about 30 seconds), after that it's instant.

2 · Install Git

Git is the tool that moves code between your laptop and GitHub (it also keeps a history of every change, which is why programmers use it for everything). You won't need to learn any Git commands today: Antigravity's AI runs them for you. It just needs Git installed on your machine first.

Windows: go to git-scm.com/download/win. The download starts automatically. Run the installer and click Next through every screen. The defaults are all correct, including the credential manager that handles GitHub login for you later.
Mac: open Terminal (Cmd+Space, type "Terminal", Enter). Paste xcode-select --install and hit Enter. Click Install on the popup. Wait a minute or two.

One last thing: tell Git who you are. Every upload to GitHub gets stamped with a name and email, and Git refuses to work until you've set them. Open a fresh terminal (on Windows, search "Git Bash" or "PowerShell" in the Start menu; on Mac, Terminal) and run these two commands, with your own name and the same email you'll use for GitHub:

git config --global user.name "Your Name"
git config --global user.email "you@example.com"

Keep the quotes, swap in your details. No output means it worked. This is a one-time thing per laptop — you never have to do it again.

Check Git installed

In that same terminal, type git --version. You should see a line like git version 2.xx.x. If it says "command not found", reinstall and let the installer add Git to PATH. Then type git config user.email — it should echo your email back.

watch: installing git in under 2 minutes

3 · Make a GitHub account

GitHub is a website where people store and share code. When your sim is done, you'll upload (or "push") it there, and that link is what you submit for the hackathon. It's how the judges see your code, how other participants can peek at what you built, and honestly a nice thing to have beyond this event: every programmer you'll ever meet has a GitHub profile, and yours starts here. It's free and takes about a minute. Already have an account? Skip this step, just make sure you remember the login.

Go to github.com/signup. Use your real email — you'll need the confirmation link.
Pick a username and password.
Enter the code GitHub emails you. Skip every "personalize your experience" screen.
Stay logged in on your browser — you'll come back to create a repo for your sim later.

4 · Install Antigravity

Antigravity is a code editor with an AI agent built in. You talk to it, it writes code and runs it. That's the whole workshop.

Go to antigravity.google. Click Download. Pick the installer that matches your OS.
Run the installer. On Mac, drag it to Applications.
Open Antigravity. When it asks you to sign in, use Google (any Gmail). That's the whole login — no other accounts, no configuration.
Skip any "import VS Code settings" or tutorial prompts. Just close them.

watch: install antigravity + first sign-in

Antigravity says "Account ineligible"?

Some Google accounts (usually school-managed ones) get blocked from Antigravity. Not your fault, and easy to route around: first try a different Gmail (a personal one, or make a fresh one in two minutes). If no Gmail works, use VS Code + GitHub Copilot instead — it's the same editor Antigravity is built on, with the same kind of AI agent. Download VS Code from code.visualstudio.com, click the Copilot icon at the top, and sign in with the GitHub account you made in step 3. The free plan is enough for the workshop. Open the chat panel, pick Agent mode, and every prompt on this site works the same there.

Save your model limit for when it counts

One thing worth knowing before you start: Antigravity's AI agent can run on several different models, and each one has a usage limit. The big, smart models (the ones marked "Pro" or "High") have the smallest limits. If you use a big model for every little thing, you can run out mid-workshop and get stuck waiting for the limit to reset. So here's the play: start on the smallest or "Fast" model in the picker. It handles most requests fine. Only switch up to a bigger model when the small one is genuinely stuck (same error twice in a row, or output that makes no sense). Think of the big model as your emergency budget, not your default.

You should now have

Python installed (sits invisibly in the background), Git installed (also invisible), a GitHub account you're logged into in your browser, and Antigravity open in front of you.

5 · Verify

In Antigravity, open the terminal at the bottom (View → Terminal, or Ctrl+`).
Run these two commands, one at a time (on Mac, type python3 instead of python):
```
python --version
git --version
```
You should see two version lines: any Python 3.10 or newer, and any Git version. (If your Python is 3.13 or 3.14, just make sure you did the pip install uv step from the callout in step 1 — that's your Taichi ticket.)
If both commands work, you're ready. Head to Build when you want to start your sim, and submit the final one on Submit whenever it's done.

watch: verify install

About Taichi

You don't install Taichi now. When we start vibecoding during the workshop, Antigravity's agent will run pip install taichi in your project's terminal on its own. One less thing to worry about. (On Python 3.13/3.14 that install will fail — that's expected, it's what the uv trick from step 1 is for. Just tell the agent to use uv and carry on.)

If something went wrong

Totally normal, setup hiccups happen to everyone. Find your symptom below:

Antigravity says it can't find Python: reinstall Python with "Add to PATH" ticked, then restart Antigravity.
git command not found: reinstall Git; on Windows use the default options.
Git says "Author identity unknown" or "please tell me who you are": you skipped the two git config commands in step 2. Run them and try again.
python --version says 3.13 or 3.14: no reinstall needed. Run pip install uv once, then run sims with uv run --python 3.12 --with taichi main.py. Full explanation in the callout under step 1.
Terminal shows a red error: copy the error, paste it into Antigravity's chat, say "fix this". It usually can.
None of the above helped: take a screenshot and drop it in chat. Someone will get you unstuck.

start building →ask in chat