PatternFeed

Crowdsourced coding anti-patterns library for smarter AI coding assistants

PatternFeed is an open-source platform where:

1. Testers submit structured bug reports when testing apps
2. AI extracts reusable "patterns to avoid" from reports
3. Library grows into an importable knowledge base for Claude Code users
4. Rewards = attribution, reputation, and access (no money required)

Quick Start

# Install globally
npm install -g patternfeed

# Search existing patterns
patternfeed search "useEffect dependencies"

# Generate CLAUDE.md rules for your stack
patternfeed generate-rules --stack react nextjs -o .claude/rules/patternfeed.md

# Start MCP server for Claude Code integration
patternfeed serve

Features

For Testers: Submit Bug Reports

patternfeed test https://github.com/example/repo

Interactive CLI guides you through:

• Context: Stack, framework versions, environment
• Bug: What went wrong (steps to reproduce)
• Expected: What should have happened
• Root Cause: Why it happened (if known)
• Fix: How it was fixed (if applicable)

AI then extracts a reusable anti-pattern from your report.

For Library Users: Import Patterns

Option 1: MCP Server (Recommended)

Add to your ~/.claude/claude_desktop_config.json:

{
  "mcpServers": {
    "patternfeed": {
      "command": "patternfeed",
      "args": ["serve"]
    }
  }
}

Claude Code can then:

• get_relevant_patterns - Get patterns for your current stack
• check_code - Check code against anti-patterns
• search_patterns - Search the library

Option 2: CLAUDE.md Generator

# Generate rules for your stack
patternfeed generate-rules --stack react nextjs typescript > .claude/rules/patternfeed.md

For Contributors: Build Reputation

No money involved, but real value:

| Tier | Requires | Unlocks | |------|----------|---------| | Contributor | 1+ verified pattern | Submit patterns, basic library access | | Reviewer | 10+ patterns, 90%+ quality | Review others' patterns, early access | | Maintainer | 50+ patterns, community election | Curate categories, merge patterns |

Every pattern has attribution: contributedBy: @your-username

Commands

# Test and submit bug reports
patternfeed test <repo-or-url>    # Interactive bug report
patternfeed submit report.json    # Submit existing report
patternfeed submit report.json --dry-run  # Preview extraction

# Browse patterns
patternfeed search <query>        # Search patterns
patternfeed search hydration --framework react
patternfeed search --category async --severity critical

# Generate rules
patternfeed generate-rules --stack react nextjs
patternfeed generate-rules --categories hooks async -o rules.md

# MCP server
patternfeed serve                 # Start MCP server (stdio)

# Initialize library
patternfeed init                  # Create local library structure

Pattern Structure

Patterns are stored as YAML files:

id: react-useeffect-missing-deps-001
title: Missing useEffect dependencies cause stale closures
context:
  frameworks: [React 18, React 19]
  languages: [JavaScript, TypeScript]
  appliesWhen: Using useEffect with variables from component scope
  categories: [hooks, state, async]
antiPattern: |
  useEffect(() => {
    console.log(count);  // Stale closure!
  }, []);  # Missing dependency
correctPattern: |
  useEffect(() => {
    console.log(count);
  }, [count]);  # Include dependencies
explanation: When useEffect dependencies are missing, the callback...
severity: high
confidence: 0.95
contributedBy: username
sourceReport: uuid
verified: true
votes: 42

Library Structure

library/
├── index.json          # Searchable index
├── schema.json         # Validation schema
└── patterns/
    ├── react/
    │   ├── hooks/
    │   └── state/
    ├── nextjs/
    │   └── hydration/
    ├── typescript/
    │   └── types/
    └── general/
        └── async/

Environment Variables

# Required for pattern extraction (submitting reports)
ANTHROPIC_API_KEY=sk-ant-...

# Optional: custom library path
PATTERNFEED_LIBRARY=/path/to/library

Development

# Clone and install
git clone https://github.com/patternfeed/patternfeed
cd patternfeed/cli
npm install

# Build
npm run build

# Link for local development
npm link

# Run in development
npm run dev  # Watch mode

Contributing

1. Find a bug in any open-source project
2. Submit a report: patternfeed test <repo>
3. AI extracts a reusable pattern
4. Community verifies the pattern
5. Your attribution stays with the pattern forever

Categories

• UI/Rendering: hydration, rendering, state, props, hooks
• Async: async, promises, callbacks, race-conditions
• Network: api, fetch, networking, caching
• Security: auth, security, validation, sanitization
• Performance: performance, memory, optimization
• Types: types, typescript
• Testing: testing, mocking, fixtures
• Database: database, orm, queries, migrations
• DevOps: deployment, build, bundling, config

Severity Levels

• Critical: Security vulnerabilities, data loss, crashes
• High: Functionality broken, significant bugs
• Medium: Unexpected behavior, edge cases
• Low: Code quality, best practices

License

MIT

Acknowledgments

PatternFeed is inspired by crowdsourced testing platforms and the idea that bugs found once shouldn't be found again. Built with Claude for pattern extraction.