A monorepo, short for a monolithic repository, is a software development strategy where code for many projects is stored in the same repository. This approach is in contrast to having one repository per project, known as a polyrepo approach.
Scaling a Codebase
When it comes to scaling a codebase, companies face a crucial decision. They can either break their codebase into smaller, separate repositories (a strategy known as polyrepo), or they can consolidate their codebase into a single repository (a strategy known as monorepo).
Polyrepo Strategy
In a polyrepo approach, each application or service is maintained in its separate repository. For instance, your main application would reside in one repository, while any shared services or libraries it uses, such as authentication or design systems, are stored in their respective repositories.
These shared components are typically published to a package manager like NPM, allowing them to be easily included and updated across various projects.
A polyrepo means each team, application, or project has its own repository and build process.
Monorepo Strategy
A monorepo consolidates code for multiple projects into a single repository. These projects, although distinct, are interconnected, often comprising related JavaScript or TypeScript packages. Projects within a monorepo can range from low-level utilities to high-level web interfaces.
Essentially, a monorepo centralizes code, promoting the organization of independent, self-contained components with well-defined boundaries and interfaces.
Monorepo vs Monolith Clarified
It's important to distinguish between a monorepo and a monolithic application. A monolithic application is one large codebase encompassing all projects and components. Conversely, a monorepo is a single repository containing multiple, independent projects. This setup supports modular development, enabling each project to be developed separately while still being part of a single version control system.
Benefits of Using a Monorepo
- Efficient Code Sharing: In a monorepo, all projects can easily share code. This encourages code reuse and simplifies the integration of shared functionality across different projects.
- Unified Dependency Management: With a monorepo, dependencies are installed once for the entire repository. This reduces version conflicts and ensures consistency across projects.
- Simplified Project Synchronization: Changing a shared component in a monorepo automatically updates all projects that use it, ensuring that all applications are always up-to-date with the latest changes.
- Enhanced Collaboration: A single repository fosters collaboration among teams, as all developers can access and contribute to the same codebase. This unified structure streamlines communication and efficiency.
- Improved CI/CD Processes: Managing continuous integration and deployment (CI/CD) pipelines are simpler in a monorepo, as there's only one repository to build, test, and deploy from.
Conclusion
Monorepos offers an effective way to manage code for multiple projects within a single repository. By promoting code sharing, simplifying dependency management, and enhancing project synchronization, monorepos ensure a resilient and scalable software development process.
