Expert JavaScript Code Review for AI-Built Apps
JavaScript is the backbone of web development and the most widely generated language by AI coding tools. Cursor, Bolt, and Replit all produce JavaScript code — often with prototype pollution risks, loose equality bugs, and missing error handling.
Common JavaScript issues we find
Real problems from JavaScript codebases we've reviewed.
Prototype pollution
AI-generated code merges user-supplied objects into prototypes via Object.assign or spread operators without sanitization, enabling property injection attacks.
Loose equality comparisons
Using == instead of === leads to type coercion bugs where '0' == false, null == undefined, and other non-obvious truthy/falsy comparisons cause silent logic errors.
Unhandled promise rejections
Async functions without try/catch or .catch() handlers cause unhandled rejection warnings and silent failures in production.
Global variable leaks
Missing 'const' or 'let' declarations create implicit globals that pollute the global scope and cause unpredictable behavior across modules.
eval() and dynamic code execution
AI tools sometimes use eval(), new Function(), or setTimeout with strings to handle dynamic logic, opening severe code injection vulnerabilities.
Memory leaks from closures and listeners
Event listeners, intervals, and closures that capture large objects are never cleaned up, causing memory consumption to grow over time.
JavaScript production checklist
Key checks before deploying your JavaScript app.
Strict equality (===) used throughout
No eval(), new Function(), or dynamic code execution
All async operations have proper error handling
No implicit global variables
Event listeners and intervals cleaned up on teardown
Input validation before object merging or property access
Minified and bundled for production
Source maps configured but not publicly exposed
Not sure if your app passes? Our code audit ($19) checks all of these and more.
Our JavaScript services
Security Review
Deep security analysis of your application — from API endpoints to database access.
Fix Bugs
We diagnose and fix bugs in AI-generated apps — from mysterious crashes to features that just don't work right.
Refactor Code
Clean up messy, duplicated, and hard-to-maintain code without breaking what already works.
Performance
Identify and fix performance bottlenecks — slow page loads, laggy interactions, and expensive operations.
AI tools that generate JavaScript code
Start with a self-serve audit
Get a professional review of your JavaScript project at a fixed price.
Security Scan
Black-box review of your public-facing app. No code access needed.
- OWASP Top 10 checks
- SSL/TLS analysis
- Security headers
- Expert review within 24h
Code Audit
In-depth review of your source code for security, quality, and best practices.
- Security vulnerabilities
- Code quality review
- Dependency audit
- AI pattern analysis
Complete Bundle
Both scans in one package with cross-referenced findings.
- Everything in both products
- Cross-referenced findings
- Unified action plan
100% credited toward any paid service. Start with an audit, then let us fix what we find.
How it works
Tell us about your app
Share your project details and what you need help with.
Get a clear plan
We respond in 24 hours with scope, timeline, and cost.
Launch with confidence
We fix what needs fixing and stick around to help.
Frequently asked questions
Is JavaScript code from AI tools safe to ship?
AI-generated JavaScript frequently contains security issues like prototype pollution, eval usage, and missing input validation. A professional review catches these before they become real vulnerabilities.
Should I use JavaScript or TypeScript?
TypeScript is almost always the better choice — it catches bugs at compile time that JavaScript only reveals at runtime. We can migrate your AI-generated JavaScript to TypeScript.
How do you review JavaScript code?
We audit for security vulnerabilities (injection, XSS, prototype pollution), runtime bugs (type coercion, async errors), memory leaks, and performance bottlenecks.
Can you fix bugs in my AI-generated JavaScript app?
Yes. We trace runtime errors, fix async handling issues, resolve scope and closure bugs, and ensure your app works reliably across browsers.
Related resources
Guides
Need help with your JavaScript project?
Tell us about your project. We'll respond within 24 hours with a clear plan and fixed quote.