Git Flow vs Continuous Integration

Introduction

• Speaker: Dave Farley, Continuous Delivery enthusiast
• Overview: Discussion on Git Flow and its compatibility with Continuous Integration (CI) and Continuous Delivery (CD)
• Acknowledgment of sponsors: Harness, Equal Experts, Octopus, Spec Flow

What is Git Flow?

• Invented in 2010 by Vincent Driessen.
• Not originally designed with CI/CD in mind.
• Structure:
  • Two main branches: develop and master.
  • Additional branches: feature branches, release branches, hotfix branches.
• Git Flow adds complexity to version control.

Continuous Integration (CI) Fundamentals

• CI's goal: Maintain a shared, accurate view of the system.
• Frequent evaluations of code changes (multiple times a day).
• Quote: "What if the engineers didn't hold on to modules for more than a moment?"
• Emphasis on evaluating changes directly in the context of production.

Issues with Git Flow

• Git Flow creates ambiguity in change management:
  • The develop branch may not reflect the definitive, production-ready state.
  • Hotfixes not merged back into develop can create discrepancies.
  • Keeping develop and master branches in sync can become cumbersome.
• Feature Branches:
  • Delaying feedback until features are deemed finished is counterproductive.
  • Risks of wasted work due to late feedback.

Alternative Strategies

• Proposal to merge changes directly into master instead of develop.
• Continuous integration should happen often to maintain a clear picture of safety and quality.
• Suggested elimination of the develop and hotfix branches.
• Trunk-based development:
  • Frequent commits to the master branch.
  • Trigger CI pipelines upon push to master.

Recent Developments in Git Flow

• Brian Finster's outreach to Vincent Driessen resulted in updates to Git Flow’s description.
• Git Flow is labeled a "legacy" workflow.
• Encouragement to adopt simpler workflows like GitHub Flow for teams practicing CI/CD.

Critique of GitHub Flow

• GitHub Flow still relies on feature branches, which can delay feedback.
• Lack of mention of CI/testing in GitHub Flow documentation raises concerns.

Conclusion

• Both Git Flow and GitHub Flow can slow down the feedback cycle and limit integration frequency.
• Continuous Integration encourages more incremental development and timely feedback.
• Continuous Integration is more effective in delivering safe, production-ready software.
• A shift in mindset is necessary for developers to adopt CI practices.