Review Code for Bugs and Performance

While IDEs like Cursor offer inline autocomplete, sometimes you need a comprehensive architectural review of a specific module. This prompt leverages Claude—widely considered the most capable model for deep coding tasks in 2026—to act as a Senior Staff Engineer reviewing your pull request.

The Prompt

Act as a Senior Staff Software Engineer performing a rigorous code review. I am going to provide you with a [LANGUAGE, e.g., TypeScript] component. 

Please review this code and provide feedback categorized exactly as follows:
1. Security Vulnerabilities: (Are there any injection risks, unhandled auth edge cases, or data leaks?)
2. Performance Bottlenecks: (Are there unnecessary re-renders, O(n^2) loops, or memory leaks?)
3. Architecture & Best Practices: (Does this violate SOLID principles? Is it testable?)
4. Refactored Version: Provide a refactored version of the code that implements your critical suggestions. Add comments explaining the changes.

Be highly critical but constructive. Do not nitpick stylistic choices (like formatting); focus on architecture, performance, and safety.

Here is the code:
[PASTE CODE HERE]

Example Output

When you run this prompt, Claude will provide a structured technical breakdown:

2. Performance Bottlenecks:

• You are calling fetchUserData() inside the React useEffect without a dependency array, which will cause an infinite render loop.
• The .filter().map() chain on line 42 iterates over the transactions array twice. For large datasets, this should be combined into a single reduce pass.

4. Refactored Version: ```typescript // … (Refactored code block with specific comments highlighting the fix for the infinite loop) ```

Tips for Customization

• Add context: The AI gives better feedback if it knows where this code runs. Add context like: “This code runs on a Node.js backend and processes 10,000 requests per minute.”
• Focus the review: If you are specifically worried about one thing, adjust the prompt: “Focus 100% of your review on finding potential SQL injection vulnerabilities.”
• Ask for tests: Follow up the review by asking, “Now, please write three unit tests using Jest that cover the edge cases you just identified.”