Compares tennis match and golf tournament prices on Polymarket, Kalshi and Pinnacle, including each venue's fees, and shows when backing both outcomes across two venues costs less than $1. Selecting a player checks the live order books to see how much could actually be traded.

Data

Polymarket, Kalshi and Pinnacle public APIs

Built with

Node serverless functions, JavaScript

Tests

9 unit tests

Takes a Solana or EVM token address and gives a score out of 100 based on contract permissions, liquidity, holder concentration, trading activity and age. Each deduction is listed with the reason.

Data

DexScreener, RugCheck, GoPlus, GeckoTerminal

Built with

Node serverless functions, JavaScript

Tests

6 unit tests

secp256k1, Keccak-256, ECDSA with public key recovery, Schnorr signatures (BIP-340) and Shamir secret sharing, written in plain JavaScript without crypto libraries. Includes a demonstration of recovering a private key from two signatures that reuse a nonce.

Built with

JavaScript BigInt, WebCrypto for SHA-256

Tests

10 tests, checked against OpenSSL and published test vectors

A Uniswap V2 style pool written in Solidity, plus a page that reads live Uniswap V2 reserves from Ethereum and calculates price impact, sandwich attacks, arbitrage against Binance and impermanent loss. The contract tests run a sandwich attack and check the result against the calculator.

Built with

Solidity, OpenZeppelin, Hardhat, JavaScript

Tests

8 contract tests, 4 JavaScript tests