Monorepo: Pros, Cons & Tools

Exploring the Pros, Cons, and the TurboRepo Solution

Monorepo
Let’s begin by assuming you’re a software developer.

In our world, the management of large codebases can be a daunting task. As projects grow in complexity and scale, developers often search for efficient ways to organize and maintain their code.

No worries ;) there is a simple solution. Let me introduce you to the use of monorepositories, or monorepos for short. In this article, we will delve into the pros and cons of monorepos, explore some of the popular tools available, and introduce you to TurboRepo, an innovative solution for managing monorepositories.

Difference between Monolith & Polyrepo &Monorepo

What is a Monorepo?

Simply put, it’s a version control repository that contains multiple projects or applications within a single repository.

In other words, it’s a one-stop shop for all your code, including libraries, applications, and even shared configurations. Let’s take a closer look at the advantages and disadvantages of adopting this approach.

Polyrepo vs Monorepo

For the sake of this discussion, let’s say the opposite of ​monorepo is a “polyrepo”. A polyrepo is the current standard way of developing applications: a repo for each team, application, or ​project. And, commonly, each repo has a single build ​artifact and simple build pipeline.​

Monorepo ≠ Monolith

Monorepo is not the same as Monolityh, quite the contrary, because monorepos simplify code sharing and cross-project refactorings. Significantly lower the cost of creating libs, microservices, and microfrontends. Adopting a monorepo enables more deployment flexibility. ​​

It’s only for the frontend…

Fronted illustration

No… a monorepo is not limited to just frontend development. While the monorepo concept is often associated with frontend projects due to the need for shared components, libraries, and consistent styling, it can be applied to a wide range of software development scenarios, including backend, full-stack, mobile, and even infrastructure projects.​

The Pros: Why is Monorepo Great

  1. Code Reusability: Monorepos encourage code reusability by allowing multiple projects to share common code, reducing duplication and ensuring consistency.
  2. Easier Collaboration: With all code in one place, collaboration becomes seamless. Developers can access and modify different projects without having to switch repositories.
  3. Streamlined Dependency Management: Managing dependencies is simplified, as all projects share a single package manager and version control system.
  4. Atomic Commits and Releases: Monorepos enable atomic commits and releases, ensuring that changes across multiple projects are always in sync.
  5. Improved Testing: Comprehensive testing becomes easier, as you can run tests across all projects simultaneously, ensuring better code quality.

The Cons: There’s a But…

  1. Complexity: Monorepos can become complex as the codebase grows, making it challenging to navigate and understand.
  2. Slower Cloning: Initial repository cloning can be time-consuming, especially for new developers joining the team.
  3. Tooling Overhead: Specialized tooling is often required for managing monorepos, which can add complexity to your development workflow.
  4. Risk of Over-Engineering: There is a risk of over-engineering by trying to fit everything into a monorepo, even when it might not be the best solution for certain projects.

How do you know when to use a monorepo?

In our day-to-day work at Ableneo, we maintain a list of scenarios that guide us in deciding when to embrace or steer clear of a monorepo. Allow me to outline a few examples that illustrate when employing a monorepository is advisable and when it may be less appropriate.

Use a Monorepo when:

  1. Shared Codebase: Multiple related projects or applications that share a significant amount of code or dependencies, a monorepo can help centralize and manage these shared resources efficiently.
  2. Code Consistency: Promote code consistency and reduce the risk of version mismatches or conflicting dependencies by ensuring that all projects use the same version of shared libraries and tools.
  3. Cross-Project Refactoring: If you frequently need to refactor code across multiple projects, a monorepo simplifies this process by allowing changes to be applied consistently to all affected areas.
  4. CI/CD: Monorepos facilitates CI/CD pipelines by enabling you to build, test, and deploy multiple projects or services from a single codebase, streamlining the automation process.
  5. Team Collaboration: Monorepos can enhance collaboration among development teams working on different parts of a project, as all code is in one place, making it easier to share knowledge, tools, and best practices.
  6. Versioning Control: If you want precise version control across all your projects, a monorepo allows you to synchronize version changes and ensure compatibility.

Avoid a Monorepo if:

  1. Small Projects: For small projects or individual applications that do not share much code or dependencies with other projects, using a monorepo may introduce unnecessary complexity.
  2. Independent Development Teams: If your development teams are completely independent and do not need to collaborate or share code frequently, a monorepo may be overkill and can hinder agility.
  3. Performance Concerns: Monorepos can become unwieldy as they grow, potentially impacting performance, especially if you have many files or extensive history. In such cases, smaller repositories may be more efficient.
  4. Complexity Overhead: Managing a monorepo can be more complex and may require additional tooling and workflows to handle dependencies, versioning, and build processes. If the added complexity outweighs the benefits, consider separate repositories.
  5. Security Concerns: If security is critical, separating projects into individual repositories can provide more granular control over access and permissions.
  6. Legacy Code: If you are dealing with legacy codebases that are difficult to refactor or integrate into a monorepo, keeping them in separate repositories may be more practical.

Popular Tools for Monorepo Management

To address the complexities of monorepos, various tools, and platforms have emerged to streamline development workflows. Some popular options include:

  1. NX: NX is a popular tool used for managing monorepositories in the context of Angular projects. It provides a set of powerful development tools and practices that enhance the development workflow within a monorepo environment.
  2. Lerna: Lerna is a JavaScript tool that optimizes the management of JavaScript projects with multiple packages.
  3. Yarn Workspaces: Yarn’s workspaces feature simplifies monorepo management for Node.js projects, making it easier to manage dependencies and scripts.
  4. Bazel: Google’s Bazel is a powerful build tool that supports monorepo workflows and provides hermetic builds and tests.
  5. Rush: Microsoft’s Rush is designed for managing monorepos with TypeScript and JavaScript projects. It helps with dependency management and builds automation.
  6. And many more…

Why Choose TurboRepo?

While the mentioned tools provide valuable solutions, TurboRepo stands out as a unique and innovative approach to monorepo management. TurboRepo is designed to overcome many of the challenges associated with monorepos, offering the following benefits:

  • Lightweight Cloning: TurboRepo introduces a novel approach to cloning monorepos, allowing developers to clone only the necessary code. This significantly reduces the time and bandwidth required for initial repository setup.
  • Flexible Workflow: TurboRepo allows you to maintain individual repositories for each project while benefiting from centralized package management and sharing code between projects.
  • Optimized CI/CD: TurboRepo’s architecture enables efficient CI/CD pipelines by building only the projects affected by a particular change, minimizing build times.
  • Versioning Control: Developers can easily manage shared library versions and configurations, ensuring project compatibility.
  • Simplified Collaboration: Collaboration remains straightforward, as developers can work in familiar Git workflows without the complexity of a single monolithic repository.

Conclusion

There are numerous advantages for large-scale software development projects, including code reusability, improved collaboration, and streamlined dependency management. However, it also presents challenges in terms of complexity and tooling overhead.

As we’ve seen, you can address these challenges with various tools, including Lerna, Yarn Workspaces, Bazel, and Rush, or you can explore innovative solutions like TurboRepo.

“The choice” of whether to adopt a monorepo and which tool to use really depends on your project’s specific needs and requirements. When making this decision, you should consider your team’s size, project scale, and development workflows. Whether you choose a traditional monorepo or explore innovative solutions like TurboRepo, the key is to find an approach that enhances your development process and empowers your team to build better software.

Monorepo: Pros, Cons & Tools was originally published in ableneo Technology on Medium, where people are continuing the conversation by highlighting and responding to this story.