PR Dojo is a practice platform for developers who want to sharpen their code review skills. We believe that the best way to become a better reviewer is by practicing on real-world code that didn't make it through review.
Every day, thousands of pull requests are rejected, revised, or merged with bugs. These rejected PRs contain valuable learning opportunities — real bugs, real edge cases, real design mistakes. PR Dojo curates these mistakes into structured challenges where you can practice identifying issues and writing fixes.
Browse our collection of buggy code snippets sourced from real rejected PRs. Each challenge includes a description, difficulty rating, and bug type categorization.
Review the code carefully, looking for logic errors, security vulnerabilities, performance issues, and style problems. Use hints if you get stuck.
Write a patch that resolves the identified issues. Submit your fix and earn XP based on the difficulty and quality of your solution.
Strong code review skills are one of the highest-leverage abilities a developer can have. Reviewing code helps you:
Our challenges span a wide range of common bug categories:
PR Dojo is an open project. If you have rejected PRs you'd like to contribute as challenges, or if you want to help build the platform, check out our GitHub repository and open an issue or pull request.