Time to Merge Metric

Definition

The Time to Merge Metric measures the total time it takes for an approved pull request (PR) to be merged into the main branch. This metric provides a comprehensive view of how quickly approved changes are finalized and integrated.

Between the approval and merging of a pull request (PR), several critical steps may take place, depending on the team’s workflow and the tools used. Below is a typical process outline:

Addressing Final Comments or Changes
- Even after approval, the author may need to address outstanding feedback, such as implementing small adjustments or fixes.
Rebasing or Resolving Merge Conflicts
- If updates to the base branch (e.g., main or develop) conflict with the PR, the author must rebase or resolve merge conflicts to ensure a smooth merge.
Executing CI/CD Pipelines
- A final set of automated checks ensures the PR is production-ready. These steps typically include:
  - Unit tests
  - Integration tests
  - Code style and linting checks
  - Security scans

Each of these steps helps maintain code quality, minimize disruptions, and ensure a seamless integration process.

Why Is This Metric Important?

Short Time to Merge: Indicates a smooth process with clear requirements, effective collaboration, and minimal blockers.
Long Time to Merge: May point to inefficiencies, such as unclear requirements, large PRs, delays in review, or conflicts in code integration.
Team Productivity: Provides a measure of how quickly the team is able to process and integrate changes.
Bottleneck Identification: Helps pinpoint stages in the workflow where delays occur (e.g., waiting for review, lengthy feedback cycles).
Code Quality and Collaboration: Encourages the creation of smaller, well-prepared PRs, which typically have faster merge times.
Release Velocity: Faster merge times contribute to quicker iteration and deployment cycles, supporting agile development practices.

How to Improve Time to Merge?

Create Smaller, Focused PRs: Smaller changes are easier to review and merge.
Improve Review Cycles: Allocate resources to ensure timely reviews.
Automate Checks: Use tools to automate testing, linting, and other checks to reduce delays.
Better Communication: Ensure clear requirements and collaboration between developers and reviewers.

Tracking the Time to Merge metric helps teams enhance their development workflows, reduce delays, and ultimately ship features faster and more effectively.