7 Review Habits That Cut PR Time 40% Without Raising Bugs

He wasn’t skimming.

He wasn’t reckless.

And the PR had zero bugs in production.

Meanwhile, I was spending 3 hours reviewing 200-line PRs, still missing critical issues, and becoming the bottleneck everyone complained about in standup.

The difference wasn’t experience. It was system.

After studying the review habits of the fastest engineers at three companies (and tracking my own PR metrics for 6 months), I found seven patterns that consistently cut review time by 40% while catching more bugs, not fewer.

Here’s what actually works.

1. The “Diff-First, Code-Second” Rule

Most developers read PRs like novels — line 1 to line N.

Fast reviewers read the diff summary first.

They spend 60 seconds understanding what changed and why before looking at a single line of code. GitHub’s “Files changed” tab becomes a roadmap:

src/auth/login.ts        (+45, -12)
src/auth/middleware.ts   (+8, -3)
tests/auth.test.ts       (+156, -0)