Stacked Diffs Changed How I Reviewed Code with AI

Key Concepts

Stacked Diffs: A workflow for creating pull requests in small, incremental changes that build upon each other, rather than one large, monolithic change.
AI Code Review: Utilizing Artificial Intelligence to assist in the code review process, providing feedback and identifying potential issues.
Graphite: A platform designed to facilitate the use of stacked diffs, offering a command-line tool and a dashboard with integrated AI assistance.
Feature Branch: A branch in a version control system (like Git) used to develop a specific feature in isolation.
Pull Request (PR): A request to merge changes from a feature branch into another branch (typically the main branch).

The Limitations of Traditional Pull Requests & Introduction to Stacked Diffs

The speaker highlights the inefficiencies inherent in traditional pull request workflows. These typically involve creating a substantial change, waiting for approval, and then repeating the process. This can create bottlenecks and slow down development. Stacked diffs offer a solution by advocating for small, incremental changes that build on top of each other to form a larger feature. This approach eliminates the wait time between each incremental step, optimizing the process for faster iteration.

Optimizing for AI Code Review

A core benefit of stacked diffs is their synergy with AI-powered code review tools. Because each diff is small and focused, the AI can provide significantly more targeted and useful feedback. Reviewing one massive pull request can overwhelm the AI and lead to less precise results. The speaker emphasizes that the focused nature of each layer within a stack diff allows for “super focused feedback.”

Graphite: A Platform for Stacked Diffs

Graphite is presented as a platform specifically designed to streamline the stacked diff workflow. It provides two key components: a command-line tool (similar to the GitHub CLI) for managing diffs within repositories, and a dashboard for overall management and AI-assisted review. The speaker notes the platform’s intuitive demo, which guides users through creating their first stack diff and subsequent pull requests.

Workflow Demonstration & Practical Implementation

The speaker describes a practical demonstration of Graphite’s workflow. This involves creating three pull requests, each building upon the previous one, to form a complete feature. The Graphite dashboard allows for managing each pull request individually, utilizing the Graphite agent for AI review, and merging the changes directly from the dashboard – eliminating the need to navigate to the GitHub repository for these actions.

The speaker clarifies that despite the streamlined workflow, the underlying mechanism still relies on standard Git practices. Each incremental change resides in a feature branch and is merged into the preceding branch, ultimately culminating in a merge into the main branch. This ensures compatibility with existing Git workflows.

AI Review Results & Comparative Analysis

The speaker references a separate video (linked in the description) demonstrating the use of Claude code to review each of the three pull requests within the stack. The results obtained from reviewing these smaller, focused diffs are described as “insane” compared to the results of reviewing a single, large pull request. This underscores the effectiveness of the stacked diff approach when combined with AI code review.

Key Argument & Perspective

The central argument is that stacked diffs, particularly when used in conjunction with AI code review, represent a significant improvement over traditional pull request workflows. This approach fosters faster iteration, more focused feedback, and ultimately, higher-quality code. The speaker positions this workflow as a “must” for validation.

Notable Quote

“And the results that you get from this compared to reviewing one massive pull request is just insane.” – The speaker, emphasizing the superior quality of feedback obtained from reviewing stacked diffs with AI.

Technical Terms Explained

Git: A distributed version control system used for tracking changes in source code during software development.
GitHub CLI: A command-line interface for interacting with the GitHub platform.
Graphite Agent: The AI-powered component within the Graphite platform used for reviewing pull requests.
Feature Branching: A software development strategy where developers create separate branches for each new feature, isolating the development process.

Synthesis & Conclusion

The speaker advocates for adopting stacked diffs as a core component of a modern software development workflow, particularly when leveraging the power of AI code review. Graphite is presented as a valuable tool for implementing this approach, offering a user-friendly interface and integrated AI assistance. The key takeaway is that breaking down large changes into smaller, incremental steps, and reviewing each step individually with AI, leads to more efficient development, higher-quality code, and faster iteration cycles.