What Is a Pull Request: why teams review code before merging

What a Pull Request is and why it isn’t a formality

A Pull Request (PR) is when you tell the team: “I made changes, please look before I add them to the main code.” Sounds simple. But a good PR is much more than a “Merge” button.

Why this exists at all

1. Finding errors before users do

A second pair of eyes often catches what the author missed: a logic error, a security issue, a poor way to handle edge cases.

2. Knowledge sharing

Through review everyone sees other people’s code and learns. Juniors understand how seniors work, seniors see unusual approaches.

3. Change documentation

A PR with a good description is a record: what changed, why, what alternatives were considered. Six months from now, someone (maybe you) will open the history and understand why things were done this way.

4. Preventing the “single point of failure”

If only one person knows how a critical part of the system works — that is a risk. Code reviews distribute knowledge across the team.

What a good PR looks like

Title

Short and clear. Not “fix stuff” but “Fix login redirect after password reset”.

Description

• What changed (1-2 sentences)
• Why (problem/user request/bug)
• How to verify (steps, screenshots, video)
• Related issues (link to tickets)

## What
Added duplicate email validation at registration.

## Why
Users were able to register with the same email multiple times.

## How to verify
1. Open /register
2. Try registering with an existing email
3. Should show "Email already registered" error

Fixes #42

How to write small PRs instead of one big one

Bad: 47 files, 1200 lines, “added user system and fixed bugs and refactored login”

Good:

• PR #1: “Add email validation utility” (3 files, 45 lines)
• PR #2: “Add duplicate email check to registration” (2 files, 30 lines)
• PR #3: “Update registration form error messages” (1 file, 15 lines)

Small PRs:

• faster to review (5–15 minutes instead of an hour);
• merge quicker;
• if something breaks, it is easier to find why;
• reviewer is less stressed.

Common mistakes

1. “It’s simple, no review needed”

Simple changes can have side effects too. Plus, a PR is not only quality control — it is documentation. Someone else needs to know what changed.

2. One gigantic PR for everything

When a PR contains 20 features, 15 bug fixes, and refactoring — the reviewer either clicks “approve” without reading (pointless) or spends an hour (also bad).

3. Ignoring reviewer comments

If someone asks you to change something — either change it or explain why you are keeping it. Silence = “I ignored it” = trust issues in the team.

4. Merging without checking CI results

If tests failed — that is not “minor, I’ll fix it later.” It is a signal that something is broken.

5. Not updating the branch from main

When someone else changed main and your branch is old — a merge conflict is inevitable. Good habit: git pull origin main before creating a PR.

Conclusion / action plan

A Pull Request is not bureaucracy. It is a tool that makes code better and the team stronger.

Here is what to do next:

1. Create a PR next time, even for small changes — it is a habit.
2. Write a description: what, why, how to verify.
3. Make the PR small — 1-3 files, one logically complete change.
4. Verify CI is green before asking for review.
5. Respond to comments — quickly and respectfully.

A good PR is a sign of professionalism. It says: “I did my work and I want the team to check it before it becomes part of our product.”