The Git Time Machine

Part A — Turn on the time machine (10 min)

Your AI will do the work — but today you'll press the buttons yourself a few times, so the magic stops being magic.

Type these, one at a time, in your terminal (yes, you — it's 4 words each. Your AI can watch and cheer):

git init

You just said: "make this folder a time-machine folder." (Only once per project. If it says a warning about your name, ask your AI: "git wants my name and email, help me set it.")

git status

This is the most-used command in software. It just looks around and reports: what's new, what changed, what's about to be saved. Read what it says. Ask your AI: "Explain this git status output in plain English, like I'm new."

Part B — Make your first save points (10 min)

Now save your About Me page. Two steps, like packing a suitcase:

1. Pack the suitcase (choose what to save):

   git add .
   

   (The . means "everything in this folder.")

2. Label and seal it (create the save point):

   git commit -m "my first save point: About Me page"
   

The -m part is a message — a note to Future You. Write messages in plain words you'd actually say: "pricing section looks good before AI touches it", not "asdf". Future You is often panicking and in a hurry; leave good notes.

Make one more save point: ask the AI for a small change, check the page, then git add . and git commit -m "..." again.

💡 Golden Rule #1: Save before you renovate. Before any big AI change, make a save point. It costs 10 seconds. Skipping it is how Lisa lost a weekend.

See your history — all your save points, newest first:

git log

(To exit the log view, press the q key. Everyone gets trapped once. Now you won't.)

Part C — The time travel moment (15 min)

This is where it stops being theory. You're going to let the AI break your site on purpose, then travel back in time.

1. Save first (Golden Rule #1): git add . and commit with a message like "last good version before the disaster drill".

2. Now, with a straight face, ask your AI:

   Make the page as ugly and broken as you can: clashing colors, huge
   chaotic text, and delete one of my sections. This is a drill — do not
   fix anything.
   

3. Look at your page in the browser. Enjoy the horror. This is what an uncontrolled AI change feels like.

4. Now the superpower. Find the save point you want to return to:

   git log --oneline
   

   (Same list, short and tidy.) Then travel back — ask your AI:

   Restore my project to the commit that says "last good version before
   the disaster drill" — undo everything that happened after it.
   

5. Refresh the browser. Your page is back. Nothing the AI does is permanent anymore. Say it out loud; it's a big deal.

Part D — Cloud backup (GitHub) (15 min)

Save points so far live on your computer. If your laptop meets a swimming pool, they die with it. GitHub is a free website that keeps a copy of your save points in the cloud. It's also where the world stores software — you're a member now.

1. Create a free account at github.com if you don't have one.

2. On GitHub, click + → New repository, name it vibe-coding-course, set it to Private, and create it. (A "repository" — or repo — is just a time-machine folder. That's the whole definition.)

3. Ask your AI:

   I made an empty private GitHub repo called vibe-coding-course.
   Connect this folder to it and push my commits. Walk me through any
   login steps — explain everything in plain English.
   

4. Open your repo on github.com and see your files and your save-point history. That's your work, safe in the cloud.

From now on, after each save point, push (upload):

git push

⚠️ Pay attention on Challenge 2: GitHub is public-ish. Pushing the wrong file there is exactly how people get hacked. One more save point first: git add . + commit + push.

Part E — Parallel universes (10 min, optional but fun)

Big idea: sometimes you want to try something wild without risking the good version. A branch is a parallel universe: experiment freely there, and if it's better, merge it back; if it's terrible, delete it and nobody ever knows.

1. Ask your AI:

   Create a git branch called wild-idea and switch to it.
   Then change my page's color scheme to neon pink and green.
   

2. Look at the page. Bold choice.

3. Now choose your ending — ask your AI for either:

   • "I hate it. Delete the wild-idea branch and switch me back to the main version." — or —
   • "Actually it's growing on me. Merge wild-idea into main."

You just did something professional developers do every day. Conceptually, you now understand one of the hardest things to teach junior engineers.