21.co is the world’s leader in providing access to crypto through simple and easy to use products. 

21.co is the parent company of 21Shares, one of the world’s largest issuers of cryptocurrency-backed exchange traded products (ETPs) – which is powered by Onyx, a proprietary technology platform used to issue and operate cryptocurrency ETPs for 21Shares and third parties.

21Shares was one of the first to issue a bitcoin ETP in 2019 and manages a suite of ETFs in the U.S., including a spot bitcoin ETF and 40’ Act vehicles.  

The company has offices in Zurich, London, and New York. 21.co was founded in 2018 by Hany Rashwan and Ophelia Snyder. Cathie Wood, Chief Executive Officer & Chief Investment Officer of ARK Invest is a board member.

About the Role:

We are at the forefront of the fintech and web3 revolution and are in search of a Senior Blockchain Engineer to spearhead our initiatives in EVM-Compatible Networks, DeFi protocols, and tokenization. This role demands not just technical excellence but the vision to translate company objectives into scalable, secure, and innovative blockchain solutions.

What You Will Be Doing:

  • Architect and develop smart contracts and blockchain-based applications with a focus on Ethereum, DeFi protocols, and tokenization strategies.
  • Collaborate closely with product managers and other stakeholders to define and achieve project goals, adapting to new priorities as our dynamic environment evolves.
  • Lead by example, ensuring best practices in software development, security, and testing are followed and encouraging a culture of quality and innovation within the team.
  • Proactively identify opportunities for process and system improvements, championing changes that enhance performance, reliability, and user experience.
  • Stay abreast of the latest developments in blockchain technology, DeFi trends, and regulatory environments to ensure our solutions are cutting-edge and compliant.

What You Need to Be Great in This Role:

  • In-depth knowledge of the Ethereum ecosystem, smart contract development, and Solidity, Typescript programming languages.
  • Experience with tokenization mechanisms and DeFi protocols, understanding their impact on the blockchain landscape.
  • Knowledge of ethers.js, web3.js and other relevant web3 libraries for interacting with Ethereum.
  • Awareness of common smart contract vulnerabilities and best practices for secure development.
  • Strong foundation in software engineering principles, with the ability to lead projects and mentor junior team members towards achieving excellence.
  • Adaptability to shifting priorities and openness to exploring new technologies and methodologies to solve complex problems.
  • Excellent collaboration skills, with a proven track record of working effectively with cross-functional teams and external partners.
  • Demonstrate technical leadership, strategic thinking, and the ability to drive projects to completion successfully.

Our Tech Stack:

  • Primary focus on Ethereum (solidity), with knowledge in other blockchains like Cardano and Solana (rust) being a plus.
  • Experience with development tools such as Foundry and Hardhat.
  • Familiarity with AWS infrastructure and its application in blockchain development environments.

Good to know:

  • OpenZeppelin Contracts: A library of secure, reusable smart contracts for Ethereum and other EVM and eWASM blockchains.
  • Slither and MythX: Security analysis tools for smart contract vulnerability detection and code optimization.
  • Tenderly: Platform for smart contract development, monitoring, debugging, and analytics on Ethereum.
  • Quicknode/Infura: Provides scalable access to blockchain networks like Ethereum, enabling deployment without having to run a full node.
  • Remix IDE: A browser-based IDE that allows for writing, deploying, and administering smart contracts written in Solidity.

This role is based in New York City and will be expected to work from our New York office in a hybrid model Monday - Wednesday.

(NYC only) Pursuant to Section 8-102 of title 8 of the New York City administrative code, the base salary range for this role is $150,000-$200,000. Total compensation packages are based on a wide array of factors unique to each candidate, including but not limited to skill set, years & depth of experience, certifications and specific office location. This may differ in other locations due to cost of labor considerations.

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