Engineering Craft › Version Control (Git)

Git

The distributed version control system almost everyone uses.

Also known as: version control system, git vcs, DVCS

Git is a tool that records the history of your files. Every saved snapshot is a commit, so you can see what changed, who changed it and when, and go back to any earlier state. It also lets many people work on the same code at once.

It’s distributed: every clone has the full history, so you can commit, browse history and create branches offline. A shared server (GitHub, GitLab) is just one more copy that the team agrees to treat as the central one. Git is not GitHub: Git is the tool; GitHub is a website that hosts Git repositories and adds pull requests and issues.

The everyday cycle

git clone <url>                  # get a copy
git switch -c fix-login          # start a branch
# ...edit files...
git status                       # see what changed
git add login.py                 # stage it
git commit -m "Fix login redirect"
git push -u origin fix-login     # share it, then open a pull request
git pull                         # bring in others' changes

Key ideas

Getting unstuck

Most Git fear comes from not knowing where you are. Run git status often, since it tells you the current branch, what’s changed and usually what to do next. A committed change can almost always be recovered (see reflog). Uncommitted work is the thing that can be lost, so commit early.