MockMouse: Cursor for QA
Inspiration
It was frustrating spending half of HackDavis' time manually clicking through our app instead of building features. At 3 AM, while other teams were adding cool features, we were stuck testing feature flows for the 50th time. That's why we built MockMouse - an AI agent that tests your web apps while you focus on what actually matters. The inspiration for MockMouse came from a simple yet frustrating observation: testing web applications shouldn’t require a computer science degree.
We saw:
- Product managers and designers struggling with test scripts
- QA engineers overwhelmed by repetitive tasks
“Login with valid credentials and check if the dashboard loads.”
Computers don't understand this.
We make them.
What It Does
MockMouse is an AI-powered application testing platform that:
- Accepts natural language test instructions
- Records and breaks down tests step by step
- Uses AI to explore and understand web apps
- Streams test runs live with visual feedback
How We Built It
Architecture Overview
MockMouse is built using a microservices-based structure with:
- Frontend (Next.js)
- Backend API (Express)
- AI Testing Infrastructure (Python, Browser-use)
Technology Stack
Frontend
- Next.js 14 + TypeScript
- Socket.IO Client for real-time streams
- Tailwind CSS for clean, modern UI
- Custom components for test and stream visuals
AI Layer (Python)
- Browser-Use library for automation
- OpenAI / Anthropic APIs for natural language understanding
- Socket.IO for real-time communication
Backend API
- Python + SocketIO for API + WebSocket support
- Supabase + Prisma for persistence
- Authentication via Clerk
Key Features
Natural Language Test Creation
Write tests like: "Login with valid credentials and check if dashboard loads."
Intelligent App Discovery
AI automatically maps apps by:
- Crawling pages
- Detecting forms and UI elements
- Building a knowledge graph of user flows
- Recognizing login/search/checkout patterns
What We Learned
Technical Discoveries
- AI Agent Design for app flow understanding
- Real-time streaming with low latency
- Handling async operations + lazy loads
- Teaching AI workflows and user intent
Product Insights
- User experience is everything
- Visual feedback builds trust
- Simplicity > Complexity, but with flexibility
Team Takeaways
- Cross-functional dev is critical
- MVPs validate assumptions early
- Design with user testing from day one
Technical Challenges
Agentic Flow with browser_use
Challenge: Designing a reusable AI loop that can navigate and test web apps using visual understanding
Solution:
- Built multi-step agentic workflows for planning and execution
- Leveraged
browser-usefor screen-based visual inference - Implemented memory and context retention across test steps
- Adapted flow to handle async behavior, modals, and visual state changes
Dynamic UIs Break AI
Challenge: Web apps change constantly
Solution:
- Retry logic with exponential backoff
- Context-aware detection models
- Fallbacks + adaptive wait logic
Browser Automation at Scale
Challenge: Avoid memory leaks & crashes
Solution:
- Browser lifecycle control
- Session isolation
- Auto-recovery from crashes
Product Challenges
Simplicity vs Power
Challenge: Powerful AI without a scary UI
Solution:
- Natural language test input
- Visual feedback for all steps
- Guided onboarding and examples
Earning Trust in AI
Challenge: Users need to understand AI actions
Solution:
- Real-time reasoning logs
- Visual AI confidence levels
- Post-test replay mode
Team Challenges
Tight Timelines
- Focused on MVP
- Used parallel dev streams
- Standardized code & docs
Complex Integration
- Clear API endpoints
- Shared TypeScript interfaces
What We’re Proud Of
Technical Wins
- Zero-downtime Python Infra
- Under 1s latency test streaming
- 99% uptime through fault recovery
- Scalable infra for multiple sessions
Product Highlights
- Easy-to-use UX for non-tech users
- Real-time, interactive test visuals
- Clear docs with walkthroughs
Innovations
- Natural Language Testing
- Context-Aware AI Agents
- Replay Mode + Visual Logs
Built with love by Team MockMouse for Berkeley Hacks 2025
Built With
- anthropic
- browser-use
- claude
- clerk
- css
- eventlet/gevent
- fastapi
- gpt-4
- jwt
- moviepy
- next.js
- node.js
- openai
- opencv
- postgresql
- pydantic
- python
- socket.io
- supabase
- tailwind
- typescript
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