npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@0xdoublesharp/sloth-vdf

v0.0.2

Published

Sloth Verifiable Delay Function for Javascript and Solidity 0.8

Downloads

9

Readme

Sloth Verifiable Delay Function

This module implements the Sloth VDF algorithm in JavaScript, TypeScript, and Soldity 0.8 for generating provable random numbers.

Install

npm install -D @0xdoublesharp/sloth-vdf
yarn add -D @0xdoublesharp/sloth-vdf

Solidity

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import { SlothVDF } from '@0xdoublesharp/sloth-vdf/contracts/SlothVDF.sol';

contract RandomVDFv1 {
  // large prime
  uint256 public prime = 432211379112113246928842014508850435796007;
  // adjust for block finality
  uint256 public iterations = 1000;
  // increment nonce to increase entropy
  uint256 private nonce;
  // address -> vdf seed
  mapping(address => uint256) public seeds;

  uint256 public proof;

  error InvalidProof();
  error AlreadyProven();

  function createSeed() external payable {
    // commit funds/tokens/etc here
    // create a pseudo random seed as the input
    uint256 _nonce = nonce++;
    seeds[msg.sender] = uint256(
      keccak256(abi.encodePacked(msg.sender, _nonce, block.timestamp, blockhash(block.number - 1)))
    );
  }

  function prove(uint256 _proof) external {
    if (proof != 0) revert AlreadyProven();
    if (!SlothVDF.verify(_proof, seeds[msg.sender], prime, iterations)) revert InvalidProof();

    // use the proof as a provable random number
    proof = _proof;
  }
}

JavaScript / TypeScript

describe('Sloth VDF', () => {
  it('Prove', async () => {
    const { sender, randomVDFv1 } = await loadFixture(fixtures);

    const prime = BigInt((await randomVDFv1.prime()).toString());
    const iterations = BigInt((await randomVDFv1.iterations()).toNumber());
    console.log('prime', prime.toString());
    console.log('iterations', iterations.toString());

    const tx = await randomVDFv1.createSeed();
    await tx.wait();

    const seed = BigInt((await randomVDFv1.seeds(sender.address)).toString());
    console.log('seed', seed.toString());

    let start = Date.now();
    const badproof = sloth.computeBeacon(seed, prime, BigInt(1));
    console.log('compute time', Date.now() - start, 'ms', 'bad proof', badproof);
    start = Date.now();
    const proof = sloth.computeBeacon(seed, prime, iterations);
    console.log('compute time', Date.now() - start, 'ms', 'vdf proof', proof);

    await expect(randomVDFv1.prove(badproof)).to.be.revertedWithCustomError(randomVDFv1, 'InvalidProof');
    await expect(randomVDFv1.prove(proof)).to.not.be.reverted;
    await expect(randomVDFv1.prove(proof)).to.be.revertedWithCustomError(randomVDFv1, 'AlreadyProven');
  });
});