CodeReview AI

The Problem

Code reviews are bottlenecks. Senior devs spend hours reviewing PRs, junior devs wait days for feedback. Automated linters catch syntax issues but miss logic bugs and architectural problems.

The Approach

Built a GitHub App that analyzes PRs using GPT-4 with custom prompts trained on best practices. It comments inline on specific lines, suggests refactors, and flags potential bugs. Integrates with existing CI/CD workflows.

The Impact

Reduced average PR review time by 40% in pilot teams. Caught 15+ production bugs before merge. Now used by 3 engineering teams internally.

Build Notes

How It Works

GitHub webhook triggers on PR open/update
Fetch diff and file contents
Chunk code into reviewable segments
Send to GPT-4 with context-aware prompts
Parse response and post as inline comments

Prompt Engineering

The secret sauce is in the prompts:

You are a senior engineer reviewing code.
Focus on:
- Logic errors and edge cases
- Security vulnerabilities
- Performance issues
- Code clarity and maintainability

Do NOT comment on:
- Style issues (leave to linters)
- Minor naming preferences
- Things that are clearly intentional

Rate Limiting

Used Redis to queue reviews and respect GitHub API limits.