Leading technology companies are increasingly adopting monorepos—single repositories that house multiple projects—to streamline development processes and enhance collaboration. This guide looks into the reasons behind this shift, highlighting the benefits, challenges, and tools facilitating enterprise monorepo adoption.
Why top tech companies are adopting monorepos
There are several compelling reasons why companies are shifting from polyrepos to monorepos, including:
Simplified dependency management
In a monorepo, managing dependencies becomes more straightforward. With all projects in a single repository, shared libraries and services are easily accessible, reducing duplication and minimizing conflicts. This setup allows for atomic commits, ensuring consistency across projects and simplifying the build process.
Enhanced collaboration and code visibility
Monorepos promote collaboration among team members by providing a single source of truth. Developers can access and manage the entire codebase more efficiently, reducing the risk of code duplication and fostering better communication. This centralized approach also simplifies code reviews and testing processes.
Streamlined development workflows
Adopting a monorepo can significantly streamline the development workflow and consolidate tooling across multiple projects. By having a single repository, teams can standardize on a single set of tools for version control, continuous integration (CI), and continuous deployment (CD). This uniformity eliminates the need for developers to switch contexts between different projects and tools, enhancing productivity.
Improved scalability and maintainability
Monorepos provide flexibility for organizing projects, especially those expected to grow in complexity and size over time. As new projects or components are added, they can be easily integrated into the existing monorepo structure, avoiding the overhead of managing separate repositories. This approach aids in code navigation, readability, and maintainability.
Monorepo adoption in tech giants
Google utilizes a monorepo containing billions of lines of code, managed by their custom-built version control system, Piper. This setup facilitates extensive code sharing and streamlined development processes, allowing for atomic cross-project commits and simplified dependency management.
Meta (Facebook)
Meta employs a monorepo managed with Sapling, enabling efficient handling of their vast codebase and supporting large-scale collaboration. This approach allows for improved code sharing and reuse, streamlined collaboration among development teams, and increased code visibility and maintainability.
Microsoft
Microsoft transitioned to a Git-based monorepo for Windows development, enhancing build efficiency and developer productivity. By consolidating their codebase, they achieved simplified dependency management and streamlined development workflows.
Uber
Uber adopted monorepos to manage their large-scale projects, focusing on centralized tooling and simplified workflows. This approach allowed for decreased friction in deploying models, increased maintainability, and reduced code duplication across different projects.
Challenges in managing monorepos
Despite their advantages, monorepos introduce complexities such as:
- merge conflicts: Frequent and overlapping code changes can lead to conflicts that are time-consuming to resolve.
- complex integration processes: Coordinating changes across multiple projects requires careful planning and execution.
- lengthy CI checks: Running tests across a large codebase can slow down the development pipeline.
Addressing these challenges is crucial for successful monorepo adoption. Luckily, there are modern tools to help mitigate these issues.
How Graphite enhances monorepo workflows
Graphite provides an end-to-end toolchain to help teams manage monorepos effectively:
Stacked pull requests for incremental changes
Graphite enables developers to stack pull requests, allowing them to break large changes into smaller, sequential pieces. This approach keeps the development process fluid, as engineers don't have to wait for one PR to merge before starting on the next.
Automated merge conflict resolution
The Graphite Merge Queue automates the rebase process, ensuring that pull requests stay in sync with the main branch. This minimizes merge conflicts and maintains the stability of the main branch for deployments.
Support for distributed teams
Graphite facilitates collaboration among distributed teams through features like a shared pull request inbox and actionable Slack notifications for asynchronous reviews. These tools help teams stay unblocked and maintain productivity across different time zones.
Conclusion
The shift towards monorepos among top tech companies underscores the benefits of unified codebases in enhancing collaboration, simplifying dependency management, and enabling large-scale refactoring. While challenges exist, particularly around scalability and access control, the adoption of specialized tools, like Graphite, and build systems can mitigate these issues, making monorepos a viable strategy for enterprise-level software development.