PipeGate

PipeGate is a decentralized API monetization protocol that changes how APIs handle payments and access control. By replacing traditional API keys with payment channels, it enables true pay-per-call pricing without gas fees for each request.

The protocol consists of three main components:

• A client-side middleware that automatically handles payment channel creation, request signing, and payment management
• A server-side middleware that verifies signatures and manages payment channel states
• A smart contract for a new payment channel creation

Key Features:

• Self-served Onbarding
• Stablecoin payment for API usage
• Automatic request signing and payment handling
• No API keys needed - just your private key for all requests
• Pay-as-you-go pricing model

This solves three critical problems:

• Managing multiple keys
• Payment gateways charging high fees to the API providers
• Solving security risks in Traditional Auth methods based on API keys

PipeGate is built using a combination of modern Web3 technologies and standard web protocols:

Core Components:

1. Smart Contracts (Solidity):

   • Payment Channel Factory for channel creation
   • Channel contracts for handling payments
   • Proxy pattern for upgradability

2. Client SDK (TypeScript):

   • Built with ethers.js for blockchain interactions
   • Uses viem for efficient byte encoding
   • Axios interceptors for seamless request modification
   • State management for channel tracking

3. Server Middleware (Rust):

   • High-performance signature verification
   • Payment channel state management
   • Request validation and processing

Technical Innovations:

1. Request Signing:

   • Custom message encoding using ABI encoder
   • Efficient byte concatenation for headers
   • Timestamp and nonce management for security

2. Payment Channels:

   • Off-chain state management
   • On-chain settlement
   • Automatic nonce tracking
   • Real-time balance updates

3. Middleware Architecture:

   • Interceptor-based design for easy integration
   • Automatic header injection
   • State synchronization between client and server

With this project, we've tried to make the complex payment channel system completely invisible to both API providers and consumers, while maintaining security and efficiency.