A Real Lesson
A beginner who couldn't code and took on freelance work with AI looked back on his first project: whenever there was a bug he'd just say "something's wrong here, fix it". The AI fixed one spot and broke another. He didn't know git, and didn't know code could be returned to a previous version, so all he could do was keep asking the AI to fix, and it got messier every round.
The first habit he learned afterwards: every time you finish an important feature, save a version that runs correctly.
Three Commands, One Habit
You can have Claude Code type these commands for you, but you should know what they mean:
git init # 在项目里开启存档功能，只做一次
git add -A && git commit -m "待办清单：添加/完成/本地保存 三项验收通过"
# 存一档，引号里写这一档做到了什么
git log --oneline # 看所有存档There's only one habit: when it passes acceptance, save. Not once a day, not after everything is done, but after every single change that passes. That way every save is a "working" one, and a rollback always lands on a working state.
When It Breaks: Reload the Save, Don't Force a Fix
The AI adds categories and breaks "mark as done". You ask it to fix that, and now "delete" is broken. At this point, stop. Don't ask for a third round.
Say to it:
「分类功能改坏了原有功能。放弃这次改动，把代码回到上一次提交（删除按钮验收通过那一档）。回去之后我们重新用 Plan 模式做分类。」It will use git checkout or git restore to bring the files back to that save. All you lose is this one failed attempt, not the whole afternoon.
自测 · 学完检查一下
想真正动手做题、记进度、攒连胜？到互动课里练。
For a beginner coding with AI, what is git's main value?
答案：Save a checkpoint for every working version, so if something breaks you can go back with one sentence
Sharing and uploading is another use of git, but what matters most to you right now is "undoable". It doesn't find bugs and it doesn't speed up the AI. It only guarantees you always have a way back.
Which of these is the best moment to save a checkpoint?
答案：After the "delete button" is built and passes acceptance, before starting on "categories"
The standard for a save is "this version works". Saving by the clock may save a broken version. Saving only at the end means no way back in the middle. Saving before checking means you don't know whether you saved a good or bad one.
True or false: a commit message of "update", "changes", or "fix" is enough, since you know what you changed anyway.
答案：False
When rolling back, you need to find "the last working one" in a list of saves, and "update" or "changes" makes them indistinguishable. Write "delete button passed acceptance" and you can pick the one to return to at a glance.
The AI has spent two rounds fixing a bug and it's getting worse each time, while the previous save passed acceptance. What's the biggest time-saver right now?
答案：Have it go back to the previous save, then redo the feature in plan mode
Two rounds of getting worse means it no longer knows what it changed, and a third round will most likely be worse still. Returning to the working save loses the least. Going back through plan mode is so the approach gets talked through first this time. Digging through code yourself or starting over both cost far more than reloading the save.
Fang has never saved a checkpoint, and now a feature is broken. Can he go back to "yesterday's working version" with one sentence?
答案：No. With no save there's no version to return to. All he can do is have the AI keep fixing or rebuild
git only records the saves you commit on purpose; it doesn't save for you automatically. The AI starts a new conversation on every launch and doesn't remember yesterday's code. The browser caches what the page looked like, not the source file. That's why "save when it passes" has to become a habit.