`git config` & Aliases — Customising Git

The Three Config Levels

Git configuration exists at three scopes, each overriding the one above it:

Level	File Location	Scope
System	`/etc/gitconfig`	All users on the machine
Global	`~/.gitconfig` or `~/.config/git/config`	Your user account
Local	`.git/config` (inside the repo)	This repository only

git config --system   # system-wide
git config --global   # your user (~/.gitconfig)
git config --local    # this repo (.git/config) — default

Essential Global Configuration

Run these once after installing Git:

# Identity (used in every commit)
git config --global user.name "Jane Smith"
git config --global user.email "[email protected]"

# Default branch name for new repositories
git config --global init.defaultBranch main

# Editor (use your IDE or a simple editor)
git config --global core.editor "code --wait"   # VS Code
git config --global core.editor "idea --wait"   # IntelliJ IDEA
git config --global core.editor "nano"          # Nano

# Pull strategy: rebase by default (keep history linear)
git config --global pull.rebase true

# Push: only push the current branch, not all tracking branches
git config --global push.default current

# Auto-prune stale remote-tracking refs on every fetch
git config --global fetch.prune true

# Always use --force-with-lease instead of --force when pushing
# (not a native Git config — use a shell alias instead — see below)

# Diff and merge tool
git config --global merge.conflictstyle diff3
git config --global merge.tool intellij
git config --global diff.tool intellij

# Enable color output
git config --global color.ui auto

# Automatically fix line endings (cross-platform teams)
git config --global core.autocrlf input    # macOS/Linux
git config --global core.autocrlf true     # Windows

# Rebase: auto-squash fixup! commits
git config --global rebase.autoSquash true

# Rebase: auto-stash dirty working tree before rebase
git config --global rebase.autoStash true

# Faster git status on large repos
git config --global core.untrackedCache true
git config --global core.fsmonitor true

View Your Configuration

# Show all config and where each value comes from
git config --list --show-origin

# Show a specific key
git config user.email
git config --global pull.rebase

Git Aliases

Aliases let you define short, memorable shortcuts for long or frequently used commands. They live in ~/.gitconfig under [alias].

Everyday Shortcuts

git config --global alias.st    "status -s -b"
git config --global alias.co    "checkout"
git config --global alias.sw    "switch"
git config --global alias.br    "branch -vv"
git config --global alias.bra   "branch -vva"
git config --global alias.d     "diff"
git config --global alias.ds    "diff --staged"
git config --global alias.unstage "restore --staged"

Pretty Log Aliases

# One-line graph with author and date
git config --global alias.lg \
  "log --oneline --graph --decorate --all \
   --format='%C(yellow)%h%C(reset) %C(cyan)%ad%C(reset) %C(green)%aN%C(reset) %s%C(auto)%d' \
   --date=short"

# Full log with stats
git config --global alias.ll \
  "log --stat --format='%C(yellow)%h%C(reset) %C(bold)%s%C(reset) %C(green)(%ad)%C(reset) %C(cyan)[%aN]' \
   --date=short"

# My commits since yesterday
git config --global alias.today \
  "log --oneline --since='midnight' --author='$(git config user.email)'"

# Unpushed commits
git config --global alias.unpushed \
  "log --oneline @{u}..HEAD"

# Unmerged branches
git config --global alias.unmerged \
  "branch --no-merged"

Workflow Aliases

# Safer force push
git config --global alias.fpush \
  "push --force-with-lease"

# Undo last commit but keep changes staged
git config --global alias.undo \
  "reset --soft HEAD~1"

# Discard ALL local changes (careful!)
git config --global alias.nuke \
  "reset --hard HEAD"

# Show last commit
git config --global alias.last \
  "log -1 HEAD --stat"

# Show all aliases
git config --global alias.aliases \
  "config --get-regexp alias"

# Prune and fetch in one step
git config --global alias.up \
  "fetch --all --prune"

# Create a fixup commit (pass the SHA as argument)
git config --global alias.fixup \
  "commit --fixup"

# Interactive rebase with autosquash from origin/main
git config --global alias.tidy \
  "rebase -i --autosquash origin/main"

Shell Command Aliases (prefix with `!`)

# Open git log in a pager with colors
git config --global alias.graph \
  "!git log --oneline --graph --decorate --all | head -50"

# Delete all merged local branches (except main, develop, master)
git config --global alias.sweep \
  "!git branch --merged | grep -vE '(main|develop|master|\\*)' | xargs -r git branch -d"

# Show the root directory of the repo
git config --global alias.root \
  "rev-parse --show-toplevel"

Sample `~/.gitconfig`

[user]
    name = Jane Smith
    email = [email protected]

[core]
    editor = code --wait
    autocrlf = input
    untrackedCache = true
    fsmonitor = true

[init]
    defaultBranch = main

[pull]
    rebase = true

[push]
    default = current

[fetch]
    prune = true

[merge]
    conflictstyle = diff3
    tool = intellij

[rebase]
    autoSquash = true
    autoStash = true

[alias]
    st     = status -s -b
    co     = checkout
    sw     = switch
    br     = branch -vv
    bra    = branch -vva
    d      = diff
    ds     = diff --staged
    lg     = log --oneline --graph --decorate --all --format='%C(yellow)%h%C(reset) %C(cyan)%ad%C(reset) %C(green)%aN%C(reset) %s%C(auto)%d' --date=short
    last   = log -1 HEAD --stat
    undo   = reset --soft HEAD~1
    fpush  = push --force-with-lease
    tidy   = rebase -i --autosquash origin/main
    up     = fetch --all --prune
    fixup  = commit --fixup
    sweep  = !git branch --merged | grep -vE '(main|develop|master|\\*)' | xargs -r git branch -d
    aliases = config --get-regexp alias

Back Up Your .gitconfig

Store your ~/.gitconfig in a dotfiles repository on GitHub. This way you can set up a new machine in minutes with all your aliases and config:

git clone [email protected]:your-username/dotfiles.git ~/dotfiles
ln -sf ~/dotfiles/.gitconfig ~/.gitconfig

Interview Questions (Senior Level)

What Git defaults should a platform team standardize for safety and consistency?
How do aliases improve productivity without obscuring critical Git behavior?
What risks come with shell aliases that wrap destructive commands?
How do you roll out and version-control team Git config baselines?

Short answer guide:

Standardize pull/push/fetch behavior and conflict style.
Keep aliases transparent, documented, and predictable.
Avoid unsafe wrappers or require explicit confirmation patterns.
Distribute via dotfiles/onboarding automation and periodic audits.

Interview Focus

Position Git config as team reliability infrastructure, not just personal convenience.

Interview Trap

Creating opaque aliases that hide destructive commands or bypass safeguards.

The Three Config Levels​

Essential Global Configuration​

View Your Configuration​

Git Aliases​

Everyday Shortcuts​

Pretty Log Aliases​

Workflow Aliases​

Shell Command Aliases (prefix with !)​

Sample ~/.gitconfig​

Interview Questions (Senior Level)​