Monorepo vs multi-repo decision in Git - Hands-On Comparison

Monorepo vs Multi-repo Decision

📖 Scenario: You are part of a small software team deciding how to organize your code repositories. You want to understand the difference between using a single repository for all projects (monorepo) versus using separate repositories for each project (multi-repo).

🎯 Goal: Learn how to create and inspect both monorepo and multi-repo setups using git commands. Understand the basic commands to initialize, add files, commit, and check repository status for both approaches.

📋 What You'll Learn

Initialize a git repository

Create files and commit changes

Understand repository structure differences

Use basic git commands: git init, git add, git commit, git status

💡 Why This Matters

🌍 Real World

Software teams often decide between monorepo and multi-repo structures to organize their code. Monorepos keep all projects in one place, making shared code easier to manage. Multi-repos separate projects, which can simplify access control and reduce repository size.

💼 Career

Understanding monorepo vs multi-repo is important for developers and DevOps engineers to manage codebases effectively, collaborate with teams, and maintain CI/CD pipelines.

1

Initialize a monorepo with two projects

Create a new directory called monorepo. Inside it, create two folders named projectA and projectB. Initialize a git repository in monorepo using git init.

Git

# Create directory monorepo with subfolders projectA and projectB
# Initialize git repository inside monorepo
# Your code here

Hint

Use mkdir to create folders and git init to start a git repository.

2

Add a config file to the monorepo

Inside the monorepo directory, create a file named config.txt with the text monorepo configuration. Use git add config.txt to stage the file.

Git

mkdir monorepo
cd monorepo
mkdir projectA projectB
git init
# Create config.txt with text and add it to git
# Your code here

Hint

Use echo to write text to a file and git add to stage it.

3

Commit the config file in the monorepo

Commit the staged config.txt file in the monorepo repository with the message Initial commit with config using git commit.

Git

mkdir monorepo
cd monorepo
mkdir projectA projectB
git init
echo "monorepo configuration" > config.txt
git add config.txt
# Commit the config.txt file with message
# Your code here

Hint

Use git commit -m "message" to commit staged files with a message.

4

Initialize two separate repositories for multi-repo

Create two directories named projectA and projectB separately. Inside each directory, initialize a git repository using git init. Then create a file named config.txt in each with text projectA config and projectB config respectively. Add and commit these files with messages Initial commit projectA and Initial commit projectB.

Git

mkdir monorepo
cd monorepo
mkdir projectA projectB
git init
echo "monorepo configuration" > config.txt
git add config.txt
git commit -m "Initial commit with config"
# Create projectA and projectB directories separately
# Initialize git in each
# Create config.txt with respective text
# Add and commit each file
# Your code here

Hint

Repeat the steps of creating directories, initializing git, creating files, adding, and committing for each project separately.

Practice

1. Which of the following best describes a monorepo in Git?

easy

A. A repository used only for backups

B. Multiple repositories each containing one project

C. A repository that only stores documentation

D. A single repository containing multiple projects together

Solution

1. Step 1: Understand the definition of monorepo

   A monorepo is a single repository that holds multiple projects or components together in one place.

2. Step 2: Compare with other options

   The other options describe different repository setups or uses, not monorepos.

3. Final Answer:

   A single repository containing multiple projects together -> Option D

4. Quick Check:

   Monorepo = single repo for many projects [OK]

Hint: Monorepo means one repo for many projects [OK]

Common Mistakes:

• Confusing monorepo with multi-repo
• Thinking monorepo is only for documentation
• Assuming monorepo means backup repo

2. Which Git command is commonly used to clone a multi-repo project?

easy

A. git merge

B. git clone

C. git init

D. git push

Solution

1. Step 1: Identify the command to copy a repository locally

   The git clone command copies a remote repository to your local machine.

2. Step 2: Check other commands for correctness

   git merge combines branches, git init creates a new repo, and git push uploads changes.

3. Final Answer:

   git clone <repo-url> -> Option B

4. Quick Check:

   Clone = copy repo locally [OK]

Hint: Clone to copy repo locally, not merge or push [OK]

Common Mistakes:

• Using git merge to copy repo
• Confusing git init with cloning
• Trying to push before cloning

3. You have a monorepo with two projects: frontend and backend. You run git status inside the frontend folder after changing a file in backend. What will you see?

medium

A. Error message about folder mismatch

B. No changes detected because you are inside frontend folder

C. Changes detected for the backend file because monorepo tracks all files

D. Only staged changes shown

Solution

1. Step 1: Understand monorepo file tracking

   In a monorepo, Git tracks all files in the single repository regardless of folder location.

2. Step 2: Effect of running git status in a subfolder

   Running git status anywhere in the repo shows changes in the entire repo, including backend files.

3. Final Answer:

   Changes detected for the backend file because monorepo tracks all files -> Option C

4. Quick Check:

   Monorepo tracks all files, status shows all changes [OK]

Hint: Monorepo status shows all changes, no matter folder [OK]

Common Mistakes:

• Thinking git status is folder-limited
• Expecting error when running git status in subfolder
• Confusing staged changes with all changes

4. A team using multi-repos notices frequent conflicts when updating shared libraries. What is a likely cause?

medium

A. Lack of centralized codebase causes version mismatches

B. Using monorepo causes conflicts

C. Git does not support multiple repositories

D. Developers forgot to commit changes

Solution

1. Step 1: Analyze multi-repo challenges

   Multi-repos separate projects, so shared libraries can have different versions causing conflicts.

2. Step 2: Eliminate incorrect options

   Monorepo is not used here, Git supports multiple repos, and forgetting commits is unrelated to shared library conflicts.

3. Final Answer:

   Lack of centralized codebase causes version mismatches -> Option A

4. Quick Check:

   Multi-repo can cause version conflicts without central code [OK]

Hint: Multi-repo can cause version conflicts without central code [OK]

Common Mistakes:

• Blaming monorepo for multi-repo issues
• Thinking Git can't handle multiple repos
• Ignoring version mismatch as cause

5. Your team has 5 small independent projects with different release schedules and teams. Which repo strategy fits best and why?

hard

A. Multi-repo, because it allows independent work and releases

B. Multi-repo, because it merges all projects into one

C. Monorepo, because it forces all teams to work together

D. Monorepo, because it simplifies dependency management

Solution

1. Step 1: Analyze project independence and release schedules

   Independent projects with different schedules benefit from separate repos to avoid interference.

2. Step 2: Match repo strategy to team needs

   Multi-repo allows teams to work independently and release on their own timelines.

3. Final Answer:

   Multi-repo, because it allows independent work and releases -> Option A

4. Quick Check:

   Independent projects = multi-repo best fit [OK]

Hint: Independent projects with different schedules use multi-repo [OK]

Common Mistakes:

• Choosing monorepo for independent projects
• Thinking monorepo forces independence
• Confusing multi-repo with merging projects