Code review is a process in which someone other than the author reads proposed changes, usually in a pull request, and gives feedback before the code is merged. Reviewers look for correctness, clarity, security problems, missing tests and consistency with the project.
Why it matters
A second pair of eyes catches bugs that the author overlooked and spreads knowledge across the team, so no one person is the only one who understands a module. Reviews also keep style and design consistent and discourage shortcuts that build up technical debt.
Example
A useful review comment is specific and explains why:
checkout.py line 42: this query runs once per cart item,
so a cart of 100 items makes 100 database calls.
Could we fetch all prices in one query?The author can act on that directly, whereas "this is slow" gives them nothing to work with.
Common mistakes
- Reviewing very large changes in one go, where attention drops; ask for smaller pull requests.
- Arguing about formatting that a linter or formatter should enforce automatically.
- Phrasing feedback as criticism of the person instead of the code.
Related
Get notified when this term updates
Plus occasional practical tips on uptime and monitoring, nothing else. Unsubscribe anytime.
This page is general information written by our editorial team and updated when documentation changes. Servers and providers differ, so test changes safely first. See our editorial policy and disclaimer.