Напиши текст вакансии для должности "Smart Contract and Blockchain Backend Developer". Название компании: "HashEx US". Расположение: Санкт-Петербург. График работы: Удаленная работа. Опыт работы: От 1 года до 3 лет. Ключевые навыки: 'JavaScript', 'Node.js', 'Blockchain', 'English', 'Solidity'

HashEx vision is to become #1 DeFi Security Provider. We believe that by providing a full stack of affordable tools and services, we can set new security standards and make the decentralized world better and safer, together. We&#39;re always looking for talented humans who are passionate about about decentralized technologies and security, and ready to build the future alongside us. HashEx is seeking a talented individual who possesses infinite curiosity and passion for security. As a Smart Contract Developer, you&#39;ll work in a team of experienced smart contract developers and auditors to deliver the new security standards on decentralized markets. Responsibilities:  Writing clear smart contracts code under senior developers supervision Writing backend services for smart contract interaction Working with existing contracts and implementing new features based on the project roadmap Working effectively within a collaboratively minded team  Qualifications:  Understanding of how Blockchains work, especially Ethereum Experience in smart contract development with Solidity programming language Willingness to learn to write very high-quality, well-tested code Passion for Open Finance/ Defi or Trading Ability to learn and adapt to a rapidly evolving tech stack Strong communication and collaboration skills Good written English  Preferred:  Good understanding of continuous integration tools and blockchain management tools Knowledge of Web3 and Ethereum development and test tools (Truffle or Hardhat) Knowledge of market structures and exchange related concepts Experience with Node.js Familiarity with decentralized finance, upgradeable smart contracts, proxy patterns, and experience working with ZeppelinOS Experience with Mocha JavaScript test framework and Chai’s assertion library Familiarity with cryptography and experience with Public Key Infrastructure (PKI)  Benefits:  Working with experienced in blockchain team that made 200+ smart contact audits and never missed high severity bugs Fast-growing and unique business challenges Writing code for projects with high TVL International working environment in a team of people who are passionate about big goals Great career opportunities in a developing company Opportunity to develop both personally and professionally Progressive salary and bonuses Remote work and flexible hours Annual corporate retreat