Why Engineering Teams Should Embrace Trunk-Based Development Over GitFlow
Introduction
Version control systems are indispensable in software development, providing the foundation for managing changes and enabling team collaboration. For fast-paced startups looking to deploy code early and often, trunk-based development is the superior workflow strategy, offering a compelling alternative to the more segmented GitFlow approach.
Overview of GitFlow
GitFlow organizes development around two primary branches: develop for integration and master for releases. It introduces additional branches for features, releases, and hotfixes, aiming to organize and streamline development and release processes. While this method can be beneficial in complex projects requiring strict staging and production environments, it often proves too cumbersome for teams needing agility and speed.
Overview of Trunk-Based Development
Trunk-based development simplifies the branching model dramatically. The core idea is for developers to work together on a single branch, the ‘trunk’, with feature branches that are very short-lived and merged back into trunk frequently. This approach emphasizes continuous integration and reduces the complexity of managing multiple branches.
Google's Adoption of Trunk-Based Development
A noteworthy advocate of trunk-based development is Google. According to Software Engineering at Google, they utilize a single repository and a trunk-based development approach to foster collaboration and maintain a high pace of innovation. The main reasons Google uses trunk-based development include:
Scalability: Handling thousands of developers working on the same codebase is feasible because changes are integrated and tested rapidly.
Rapid Integration: Continuous integration aids in the early detection of conflicts and bugs, leading to higher code quality and stability.
Collaboration and Visibility: Developers have a complete view of the codebase, improving transparency and collaboration across teams.
My Experience: Implementing Trunk-Based Development at KidPass
When I started KidPass, I initially adopted GitFlow, drawing from my prior experience at The Economist. However, it quickly became evident that the methodical and segmented nature of GitFlow was impeding our development speed and flexibility. In response, I shifted our approach to a trunk-based development model, which streamlined our processes significantly and enhanced our ability to deploy more rapidly and frequently.
In our version of trunk-based development, developers work on short-lived feature branches that are merged into the main branch after pull request approval. Each developer is also responsible for deploying their changes to production, ensuring that the main branch is always production-ready. This approach empowers our team to maintain a high deployment frequency and immediate responsiveness. For features requiring UX review, developers collaborate directly with the UX team, demonstrating the functionality in a development environment or on a staging server. This direct collaboration accelerates the review process and ensures that all features meet our user experience standards before going live.
Impact on the Organization
Adopting trunk-based development had a transformative impact beyond the engineering team. It forced the rest of the organization, particularly the product team and designers, to move more quickly. Product managers and designers were compelled to think strategically about delivering the most useful parts of a feature more quickly into the user’s hands, enhancing overall productivity and accelerating the feedback loop from our users.
Comparative Analysis
Comparing GitFlow and trunk-based development, the latter offers several advantages:
Speed and simplicity: Trunk-based development reduces the overhead of managing multiple long-lived branches, accelerating the development cycle.
Continuous Integration: Regular commits and deployments improve integration, facilitating early issue detection and resolution.
Adaptability: Feature flags in trunk-based development provide more flexible and controlled feature releases without disrupting the main application.
Conclusion
Switching to trunk-based development at KidPass revolutionized our deployment practices, enabling faster releases and more dynamic responses to our service needs. It’s an effective strategy for teams aiming to enhance their efficiency and adaptability in software development.
