RareSkills

// this contract is buggy, don't use in production!
pragma solidity 0.8.28;

import {IERC20Errors} from "@openzeppelin/contracts/interfaces/draft-IERC6093.sol";
import {IERC20} from "@openzeppelin/contracts/interfaces/IERC20.sol";

contract RebasingERC20 is IERC20Errors, IERC20 {

    uint256 private _totalShares;
    mapping(address => uint256) private _shares;

RareSkills

RareSkills

include "circomlib/bitify.circom";
include "circomlib/gates.circom";

// CalculateTotal and QuinSelector taken from
// https://github.com/darkforest-eth/circuits/tree/master/perlin
template CalculateTotal(n) {
    signal input in[n];
    signal output out;

    signal sums[n];

RareSkills

1. Revert with no data
2. Revert with 4 bytes
3. Revert with 4 bytes + argument
4. Revert with Panic
5. Revert with Error
6. Return 42
7. Calldata length
8. Double calldata
9. Calculator

RareSkills

get_D() and get_y() in Curve StableSwap

Two of the most math-heavy functions in Curve V1 are get_D() and get_y().

In Curve V1 (StableSwap), D behaves similarly to k in Uniswap V2 — the larger D is, the “further out” the price curve will be. D changes — and needs to be recomputed — after liquidity is added or removed, or a fee changes the pool balance.

If a curve pool holds two tokens, x and y, the StableSwap invariant is

$$ 4A(x + y) + D = 4AD+\frac{D^3}{4xy}

RareSkills

p = 21888242871839275222246405745257275088548364400416034343698204186575808495617

# replicates the constraints Num2Bits and Bits2Num use
def constrain_modulo_p(bits, num, p):
    multiplier = 1
    acc = 0
    for i in range(len(bits)):
        assert bits[i] == 0 or bits[i] == 1
        acc = (acc + multiplier * bits[i]) % p
        multiplier = (multiplier * 2) % p

RareSkills

pragma circom 2.1.8;
include "./node_modules/circomlib/circuits/multiplexer.circom";
include "./node_modules/circomlib/circuits/comparators.circom";

// checks if the second array is a 
// permutation of the first based on
// the advice 
template ForceIsPermutation(n) {
    signal input in1[n];
    signal input in2[n];

RareSkills

const Web3 = require('web3');

// Initialize web3 instance
const web3 = new Web3('your rpc endpoint');

async function getNFTsOwnedByAddress(contractAddress, ownerAddress) {
    // Create a new contract instance
    const contract = new web3.eth.Contract([
        {
            "anonymous": false,

RareSkills

import { useAccount, useConnect } from "wagmi";
import SendFunds from "./RareSend";
import { useEffect } from "react";
import styles from "@/styles/Home.module.css";
import { MintNFT } from "./mint";

export default function Home() {
  const { connect, connectors } = useConnect();
  const { isConnected } = useAccount();

RareSkills

// Initialize ethers.js and wagmi dependencies
import { ethers } from "ethers";
import * as React from "react";
import {
  usePrepareContractWrite,
  useContractWrite,
  useWaitForTransaction,
} from "wagmi";
import styles from "@/styles/Home.module.css";