Feat/0xmeta

[0xmetaHQ]

Description

This PR adds 0xmeta.ai, a production-ready x402 payment facilitator implementation in Python (FastAPI). 0xmeta.ai enables merchants to accept crypto payments (USDC) on Base with EIP-3009 settlements.

Tests

End-to-End Payment:

• User connects wallet to merchant api
• User signs EIP-3009 authorization
• Payment verified and settled via 0xmeta
• $0.01 fee collected from merchant
• User granted access to protected content

Test Coverage

# Run tests (when implemented)
cd examples/python/x402
uv run pytest tests/ -v

# Current manual test results:
✅ Verification: PASS
✅ Settlement: PASS  
✅ Fee Collection: PASS (with merchant approval)
✅ Webhook Handling: PASS
✅ Error Cases: PASS

Checklist

• [x] I have formatted and linted my code
• [x] All new and existing tests pass
• [x] My commits are signed (required for merge) -- you may need to rebase if you initially pushed unsigned commits

Additional Quality Checks

• [x] Code follows x402 specification (v1)
• [x] EIP-3009 signature verification implemented correctly
• [x] Proper error handling and logging throughout
• [x] Environment variables documented in .env.example
• [x] README.md includes setup and usage instructions
• [x] API endpoints documented with examples
• [x] Security best practices followed (no hardcoded secrets)

[cb-heimdall]

🟡 Heimdall Review Status

Requirement	Status	More Info
Reviews	🟡 0/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1

[vercel[bot]]

@0xmetaHQ is attempting to deploy a commit to the Coinbase Team on Vercel.

A member of the Team first needs to authorize it.