Various DeFi scripts and examples

The demonstration of a fake EIP2612 signature for stealing ERC20 tokens with Permit2

A smart contract utilizing the permit2 feature allows users to define and authorize a set of executionss they wish to perform. They can also specify the amount of ERC20 tokens they are willing to pay to relayers for executing these operations.

example usage of uniswap's universal router using smart-order-router sdk and permit2 sdk

A public good pre-authorized debit program on Solana. Enables single and recurring scheduled debits from a token account.

The Core Protocol

A basic integration of Permit2 using Hardhat

Signature creation helper for Uniswap Permit2

Efficiently verify ERC20 token 'permit' functions with this TypeScript-based Node.js utility. Supports EIP-1967, OpenZeppelin proxies, and parallel processing.

Buyer SDK for HTTP 402 USDC micropayments — one-line pay() to access any x402-enabled API. XPay protocol client for EVM.

Seller test server for the x402 protocol — Express middleware demo for testing x402 USDC micropayments. XPay seller endpoint.

Community-maintained reference for the Turbine Alpha HTTP API by PropellerHeads

Open-source crypto payments. Gasless one-time + recurring billing on 7 EVM chains (USDC/USDT/WETH/WBTC/DAI/PYUSD via EIP-2612, Permit2, DAI-permit) plus scaffolded Solana/Bitcoin/Litecoin. Non-custodial, self-hostable.

EIP-2612 and Permit2 signature utilities for Foundry tests

x402 payment facilitator for Flow EVM (eip155:747)

A permit2 SDK fork from Uniswap and get it on Ethers v6

simple Permit2-based bank contract that demonstrate how Permit2 works

Permit2 integration helper for Base L2 — gasless token approvals, signature-based transfers, and batch permit utilities

⌨️ CLI tool for parsing all Permit2 payments from all UBQ issues for an upcoming airdrop

Modular, gas-optimized DeFi route processor for multi-protocol swaps, Permit2 operations, and LST/LRT conversions