Git for DevOps Engineers

git checkout -b fix/broken-deploy
# Make changes, push, create PR
git push origin fix/broken-deploy
# After review, squash merge to main

# Feature branch
git checkout -b feature/new-api develop

# Release branch
git checkout -b release/1.2.0 develop

# Hotfix
git checkout -b hotfix/security-patch main

# Merge — preserves history, creates merge commit
git checkout main
git merge feature-branch

# Rebase — linear history, cleaner log
git checkout feature-branch
git rebase main
git checkout main
git merge feature-branch  # Fast-forward

git rebase -i HEAD~3

pick abc1234 Add initial config
squash def5678 Fix typo in config
squash ghi9012 Add missing field

# Hotfix: apply one commit from develop to main
git checkout main
git cherry-pick abc1234

# Cherry-pick without committing (stage only)
git cherry-pick --no-commit abc1234

git bisect start
git bisect bad          # Current commit is broken
git bisect good v1.0.0  # This tag was working

# Git checks out a middle commit — test it
# Then mark it:
git bisect good  # or git bisect bad

# Repeat until Git finds the culprit
git bisect reset  # Return to original branch

git stash
git stash list
git stash pop        # Apply and remove
git stash apply      # Apply and keep
git stash drop       # Remove without applying

# Undo last commit (keep changes staged)
git reset --soft HEAD~1

# Undo last commit (keep changes unstaged)
git reset --mixed HEAD~1

# Undo last commit (discard changes)
git reset --hard HEAD~1

# Undo a pushed commit (creates new commit)
git revert abc1234

# Recover deleted branch
git reflog
git checkout -b recovered abc1234

cat > .git/hooks/pre-commit << 'EOF'
#!/bin/sh
terraform fmt -check
if [ $? -ne 0 ]; then
  echo "Run 'terraform fmt' before committing"
  exit 1
fi
EOF
chmod +x .git/hooks/pre-commit

{
  "husky": {
    "hooks": {
      "pre-commit": "lint-staged"
    }
  }
}

# Terraform
.terraform/
*.tfstate
*.tfstate.backup
*.tfplan

# Ansible
*.retry
inventory/*.cache

# Docker
docker-compose.override.yml

# Secrets
.env
*.pem
*.key
vault_pass.txt