TypeScript SDK

The T402 TypeScript SDK provides comprehensive support for HTTP-native stablecoin payments across multiple blockchains.

v2.0.0 Released - All packages are now published under the @t402 namespace on npm.

Core Packages

Package	Version	Description
`@t402/core`	2.0.0	Protocol types and HTTP utilities
`@t402/extensions`	2.0.0	Protocol extensions and helpers

Blockchain Mechanisms

Package	Version	Description
`@t402/evm`	2.2.0	EVM chains (Ethereum, Arbitrum, Base, etc.) with EIP-3009
`@t402/svm`	2.0.0	Solana blockchain with SPL token transfers
`@t402/ton`	2.1.0	TON blockchain with USDT Jetton support
`@t402/tron`	2.0.0	TRON blockchain with TRC-20 USDT

WDK Integration (Tether Wallet Development Kit)

Package	Version	Description
`@t402/wdk`	2.0.1	Tether WDK integration for self-custodial wallets
`@t402/wdk-gasless`	1.0.0	Gasless payments via ERC-4337 account abstraction
`@t402/wdk-bridge`	1.0.0	Cross-chain bridging via LayerZero OFT
`@t402/wdk-multisig`	1.0.0	Safe multi-signature wallet support

HTTP Server Frameworks

Framework	Package	Version
Express.js	`@t402/express`	2.0.0
Next.js	`@t402/next`	2.0.0
Hono	`@t402/hono`	2.0.0
Fastify	`@t402/fastify`	2.0.0

HTTP Client Libraries

Client	Package	Version
Fetch API	`@t402/fetch`	2.0.0
Axios	`@t402/axios`	2.0.0

UI Components

Package	Version	Description
`@t402/paywall`	2.0.0	Universal paywall component (framework-agnostic)
`@t402/react`	2.0.0	React hooks and components
`@t402/vue`	2.0.0	Vue 3 composables and components

Tools

Package	Version	Description
`@t402/cli`	2.0.0	Command-line tools for testing and development
`@t402/mcp`	1.0.0	MCP server for AI agent payments

Quick Install

# Core + EVM (most common)
pnpm add @t402/core @t402/evm
 
# With Express middleware
pnpm add @t402/core @t402/evm @t402/express
 
# Full client setup with fetch wrapper
pnpm add @t402/core @t402/evm @t402/fetch
 
# Multi-chain support
pnpm add @t402/core @t402/evm @t402/svm @t402/ton @t402/tron

Architecture

@t402/core              Base types, HTTP utilities
    │
    ├── @t402/evm       EVM mechanism (EIP-3009, ERC-4337, LayerZero)
    │
    ├── @t402/svm       Solana mechanism (SPL tokens)
    │
    ├── @t402/ton       TON mechanism (Jettons)
    │
    ├── @t402/tron      TRON mechanism (TRC-20)
    │
    └── @t402/wdk       Tether WDK integration
        │
        ├── @t402/wdk-gasless   ERC-4337 gasless payments
        │
        ├── @t402/wdk-bridge    LayerZero cross-chain bridge
        │
        └── @t402/wdk-multisig  Safe multi-sig wallets

Requirements

Node.js 18+ or Bun 1.0+
TypeScript 5.0+ (recommended)
ESM or CommonJS supported

@t402/wdk-gasless