Last modified: November 16, 2023
This article is written in: 🇺🇸
When managing software projects, organizations often need to choose between two distinct codebase structuring strategies: monorepos and multirepos. This decision isn’t just about where code lives—it affects collaboration, tooling, versioning, and even deployment practices. When you’re starting out or scaling up, it’s important to understand the strengths and trade-offs of each strategy so you can decide what fits your team and project needs.
A monorepo consolidates all projects, applications, libraries, and services into a single repository. This setup encourages centralized collaboration and simplifies dependency management, making it easier for large teams working on tightly coupled, interconnected components. With a monorepo, every change is tracked in one place, and unified versioning is simpler to enforce. For example, you might run a command like this to view the structure of a monorepo:
$ tree -L 2
.
├── apps
│ ├── app1
│ └── app2
├── libs
│ ├── lib1
│ └── lib2
└── services
├── service1
└── service2
The output above shows a clear hierarchy where all code is under one roof. This structure makes it easier to coordinate changes across projects and maintain consistency across shared components. However, it can also mean that even small changes may impact unrelated projects, so strict testing and integration practices become essential.
On the other hand, a multirepo strategy divides each project or component into its own repository. This separation gives teams greater autonomy; each team can work independently, adopt different technologies, and maintain tailored workflows that suit their part of the system. Modular architectures especially benefit from this setup. An example of what the repository layout might look like is:
$ ls
app1/ app2/ lib1/ service1/
Here, each directory is a standalone repository. This separation can lead to faster performance on version control operations and provides flexibility to deploy and scale components independently. It also reduces the complexity inherent in managing a very large codebase, as changes are isolated to specific repositories. Of course, this approach requires robust inter-repository coordination, as dependencies and shared code need to be managed separately.
A monorepo is a single repository that contains all the code for a project—even if that project consists of multiple applications, libraries, or services. This structure is particularly well-suited to large, monolithic codebases and teams requiring close collaboration and frequent code reuse.
+---------------------------------------+
| |
| MONOREPO |
| |
| +-------+ +-------+ +-------+ |
| | Proj1 | | Proj2 | | Proj3 | |
| +-------+ +-------+ +-------+ |
| |
| Shared Libraries & Dependencies |
| |
+---------------------------------------+
I. Centralized Collaboration
II. Unified Dependency Management
III. Streamlined Refactoring
IV. Optimized Build and Test Pipelines
V. Atomic Commits
I. Repository Size and Performance
II. Branching Complexity
III. Potential for Tight Coupling
IV. Steep Onboarding Curve
V. Complex CI/CD Configuration
VI. Risk of Force Pushes
A multirepo approach utilizes separate repositories for each project or component. Each repository contains its own code, dependencies, and versioning history. This strategy is often preferred for service-oriented architectures or projects comprising relatively independent modules.
+-------+ +-------+ +-------+
| | | | | |
| Repo1 | | Repo2 | | Repo3 |
| | | | | |
| Proj1 | | Proj2 | | Proj3 |
| | | | | |
+-------+ +-------+ +-------+
+--------------------------------------+
| Shared Libraries & Dependencies |
+--------------------------------------+
I. Clear Independent Versioning
II. Improved Git Performance
III. Team Autonomy
IV. Greater Flexibility
I. Challenging Dependency Coordination
II. Risk of Siloed Development
III. Harder Code Reuse
IV. Complex Deployment Orchestration
Ideal if each service or component has its own release cycle, reducing the need for a single repository to coordinate all updates.