Code Review

32 posts

microsoft3 min readCurated summary

Enhancing Code Quality at Scale with AI-Powered Code Reviews

Microsoft developed an AI-powered pull request reviewer to reduce routine review work, catch defects earlier, and help developers merge code faster. What began as an internal experiment now supports more than 90% of Microsoft’s PRs—over 600,000 per month—and has influenced GitHub’s Copilot for Pull Request Reviews. The central lesson is that AI works best as a human-in-the-loop assistant embedded directly into existing workflows. ## Addressing PR Review Bottlenecks - Human reviewers often spend time on style issues and minor bugs while overlooking architectural or security concerns. - Large, multi-file PRs can lack sufficient context and may wait days or weeks for review. - The AI reviewer automatically joins new PRs and handles repetitive or easily missed checks, allowing humans to focus on higher-level decisions. ## AI-Powered Review Features - **Automated comments:** Flags issues such as missing null checks, error-handling problems, sensitive-data risks, inefficient algorithms, and style inconsistencies. - **Suggested fixes:** Provides corrected snippets or alternative implementations, but authors must explicitly review and apply changes. AI does not commit changes automatically. - **PR summaries:** Generates descriptions of the change and highlights key modifications across the diff. - **Interactive Q&A:** Reviewers can ask questions about parameters, code behavior, or the impact on other modules directly in the PR discussion. - **Workflow integration:** The assistant behaves like a normal reviewer, requiring no separate tools or interfaces and optionally engaging as soon as a PR is opened. ## Effects on Quality and Development Speed - AI-assisted reviews reduced median PR completion times by 10–20% in early studies across 5,000 repositories. - Early feedback reduces waiting time, back-and-forth cycles, and the chance that minor issues delay approval. - The system has identified bugs such as missing null checks and incorrectly ordered API calls before they reached production. - Developers, particularly new hires, can use the explanations as continuous guidance on coding standards and best practices. ## Team-Specific Customization - Teams can configure repository-specific review guidelines. - Custom prompts support specialized checks, including regression detection based on historical crash patterns and validation of deployment or change gates. - This extensibility allows the reviewer to address concerns beyond generic code quality rules. ## Feedback Between Internal and External Products - Microsoft’s internal deployment provided early feedback on review quality, usability, and developer trust. - Internal experiments helped shape features such as inline suggestions and human-controlled change application. - These lessons contributed to GitHub Copilot for Pull Request Reviews, which reached general availability in April 2025. - Microsoft also uses learnings from GitHub’s broader external adoption to improve its internal development practices, creating an ongoing feedback loop between first-party and third-party products. Overall, the post recommends treating AI review as an always-available first pass—not a replacement for human judgment. Its greatest value comes from seamless integration, strong customization, and keeping authors and reviewers accountable for final decisions.

Read original(opens in new tab)
figma2 min readCurated summary

Figma's engineering values | Figma Blog

Figma’s engineering values were created to preserve effective collaboration as the team grows without promoting a monoculture. They are intended to describe existing behaviors, guide decisions, and make explicit the tradeoffs behind how the team works. The post focuses on communication, teamwork, feedback, inclusion, and sustainable growth. ## Communicate Early and Often - Share design documents, product specifications, architecture sketches, and works in progress before implementation is complete. - Early communication helps teams: - Identify problems before significant effort is invested. - Solve problems collaboratively rather than in isolation. - Encourage people to ask for help and exchange knowledge. - Feedback must be welcomed as seriously as it is requested; sharing is useful only when people are receptive to changing direction. - Communication is not a rigid process: - Code may be the clearest way to discuss an idea. - Simple bug fixes or obvious changes may not require extensive discussion. - This value rejects the “solo genius” model in favor of using the team’s collective expertise. - The tradeoff is slower decision-making: involving more people can require additional discussion and iteration to ensure diverse voices are heard. ## Lift Your Team - Engineers should help one another grow, prioritize teammates’ success and well-being, and create an inclusive environment. - The emphasis is on lifting the team—not sacrificing individual sustainability for the company’s interests. - The value supports: - Continuous learning and mentorship. - Weekly technical talks. - Formal onboarding mentorship. - Encouragement to develop new skills. - Feedback should focus on ideas and work rather than attacking individuals. - Insults, condescension, and belittling are considered ineffective feedback. - Team members are also expected to receive feedback thoughtfully and remain open to others’ ideas. Figma’s approach is to make collaboration and mutual growth explicit expectations while acknowledging their costs. Teams adopting similar values should define concrete behaviors, ensure feedback is genuinely welcomed, and state the tradeoffs they are willing to accept.

Read original(opens in new tab)