Trunk-Based Development

Trunk-Based Development is a version control strategy where developers merge small, frequent updates to a single branch, typically called the "trunk" (or main). It is a key practice for Continuous Integration and Continuous Deployment (CI/CD).

Core Principles

Single Source of Truth

Everyone works on the same branch. Long-lived feature branches are avoided to prevent "merge hell" and ensure that the codebase is always in a deployable state.

Frequent Commits

Developers push their changes multiple times a day. This ensures that the code is constantly integrated, and any conflicts are small and easy to resolve.

Visualizing the Flow

In Trunk-Based Development, the "trunk" is a straight line, with very short-lived branches that are created and merged back within hours or a day.

Automated Testing

To maintain the stability of the trunk, robust automated testing (unit, integration, and end-to-end) is essential. Every commit is verified before and after being merged.

Feature Flags

When large features take more than a day to complete, they are hidden behind Feature Flags (or toggles). This allows the code to be merged into the trunk without exposing the unfinished feature to users.

Visual Flow

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Trunk-Based Development is preferred by high-performing teams for its ability to reduce lead times and increase deployment frequency.