Pull Request (PR): essential definition

Definition

A pull request (PR) is the standard mechanism for proposing changes in a Git-based workflow. It encapsulates a set of commits, a human-readable diff, automated checks, and a discussion thread so the team can evaluate correctness, security, performance and product impact before merging into the target branch. Mature teams regard the PR as the source of truth for the 'why' and the 'how' of a change, from design rationale to the deployment and rollback plan.

Typical workflow

Start from an up-to-date base branch, create a feature branch, and commit in small, coherent increments. Push your branch, then open a PR with a clear, action-oriented title and a concise scope. Link relevant issues, add screenshots or videos, and note any migrations or visible impacts. Request the appropriate reviewers and code owners. CI runs automatically (formatting, linting, type checking, tests, build, security). Iterate until you have green checks and approvals, then merge using the appropriate strategy, clean up the branch, and publish release notes if necessary.

An effective review process

Reviewers focus on correctness, security, architectural fit, performance, readability, and test coverage. Prefer specific, constructive comments; distinguish blocking issues from minor details; offer concrete suggestions when appropriate. Authors clarify intent, respond promptly, and keep the PR synchronized with the base branch. Mark conversations as resolved once addressed; stale PRs should be rebased or closed to clean up the backlog.

Merge strategies and history

Three common approaches: Merge Commit (preserves history and context), Squash & Merge (a clean commit that captures the PR’s final state), and Rebase & Merge (ensures a linear history). Squash is often preferred for feature branches; merge commits are useful for collaborative efforts; rebase is ideal when a strictly linear history is required. Choose a strategy per repository and document exceptions.

CI checks and automation

Automate repeatable checks: formatting, linting, type checking, unit/integration/E2E tests, builds, preview environments, security scans (SAST/DAST), dependency and license checks, size budgets, and database migrations. Protect target branches with required checks and approval rules. Use bots to label, assign, update changelogs and, if desired, auto‑merge when all criteria are met.

PR Templates and Draft PRs

A PR template helps capture the 'why' and the 'how': the problem, the proposed solution, screenshots, test plan, migration notes, risks, deployment/rollback strategy, and links to the specification. Draft PRs are ideal for early feedback — mark them ready for review when the scope is stable.

Best practices

Prefer small, focused PRs (a few hundred lines of diff), descriptive titles and summaries, atomic commits, up-to-date tests and docs, and avoid mixing unrelated refactors. Use commit conventions (Conventional Commits) to keep the history scannable. In the description, emphasize the 'why' rather than repeating the diff.

Common pitfalls

Overly large PRs, merges without review, ignored tests, force-pushing during a review without context, unrelated changes included in the same PR, flaky checks masking regressions, missing migrations or rollbacks, and lack of consideration for performance or accessibility.

Security and compliance

Enable secret scanning, dependency updates, and code-scan alerts. Require approvals from code owners for sensitive areas and a second review if necessary. Sign commits when required, avoid logging sensitive data, and treat the PR as an audit artifact with traceable decisions and controls.

Working in a monorepo

In a monorepo, a PR can touch multiple packages. Limit the scope to a coherent change, run only the affected tests, and coordinate with the owners. Use changesets or a release tool to record versions and release notes. Keep cross-package refactors small, or split them into incremental PRs.