Signing Commits & Pro Config

Signing commits (trust)

Anyone can set user.name to yours and commit as "you". Signed commits (GPG or SSH) cryptographically prove authorship - hence GitHub's green "Verified" badge.

$ git config --global commit.gpgsign true
$ git config --global user.signingkey <key-id>
$ git commit -S -m "Signed commit"    # -S signs a single commit

Config levels & aliases

Scope	Flag	File
System	`--system`	`/etc/gitconfig`
Global (you)	`--global`	`~/.gitconfig`
Local (repo)	`--local`	`.git/config`

More specific wins: local overrides global overrides system.

$ git config --global alias.lg "log --oneline --graph --all"
$ git config --global alias.st status
$ git lg      # now your custom shortcut

Tip: A few aliases (lg, st, co) and pull.rebase=true will noticeably speed up your daily Git. Set once with --global and every repo inherits them.

Goal: You've now covered Git end to end - fundamentals, branching, collaboration, history surgery, and the professional power tools. Pair each topic with the Git labs to make it muscle memory.