Unit 8 — Version Control & Collaborative Development

Learning objectives

• Use commits as coherent records of change.
• Work with branches, pull requests, and code review.
• Resolve integration conflicts while preserving intent.

Commit quality

A useful commit is small enough to understand, has one coherent purpose, and leaves the repository in a valid state when practical.

Good commit messages explain intent:

fix(auth): reject expired password-reset tokens

The reset endpoint previously checked signature validity but not token age.
Add expiry validation and regression tests for boundary cases.

Pull requests

A pull request should make review easier by stating:

• What changed.
• Why the change is needed.
• How it was tested.
• Which issue/requirement it addresses.
• Important risks or design decisions.

Code review

Review for correctness, clarity, testability, security, maintainability, and consistency. Review the design and assumptions—not only syntax.