Senior Backend Engineer (Web3)

CoW DAO is on a mission to protect Ethereum users from MEV and optimize trade execution across DeFi. We achieve this through the CoW Protocol, CoW Swap (a leading intent-based DEX aggregator), and the innovative MEV Blocker, which together help secure, aggregate, and route trades for optimal outcomes. We also fund values-aligned projects via the CoW Grants Program.

CoW Protocol is consistently ranked among the top DEX aggregators by monthly volume and is the largest intent-based exchange. Our MEV Blocker protects trades from harmful MEV extraction and is integrated across the Ethereum ecosystem. The CoW AMM is the only live AMM designed to protect liquidity providers from LVR (loss-versus-rebalancing).

With over 100 open-source repositories on GitHub, we're transparent, community-driven, and deeply committed to the open-source ethos. Our real-time Dune Analytics dashboard showcases billions in cumulative trading volume and a rapidly growing user base. As we continue to scale, CoW DAO remains at the forefront of DeFi innovation, prioritizing security, efficiency, and decentralization.

Learn more

Location: We are a fully remote team, and although we hire almost globally, there is a preference for this role to be based in Europe or remote +/- 4 hours CEST time

Please note we’re not hiring from the US, Australia, or New Zealand

Position: Full-time contractor

We are looking for an enthusiastic, self-motivated, Senior Backend Engineer to help us build the next generation of decentralised trading protocols. As a dedicated backend engineer, you will gain ownership of our existing backend services and influence the creation, design, and execution of future features and products. You will work on technically challenging aspects of our off-chain services and our developer-facing APIs and help ensure the delivery of reliable and performant features to improve CoW Protocol.

Our Tech Stack

• Backend Code: Rust, Tokio, Cargo, Git (https://github.com/cowprotocol/services)

• Infrastructure: Pulumi, AWS, Docker, Kubernetes, Grafana, Prometheus, Elasticsearch

• Other codebases: Typescript, Python, Solidity

• Architect and design our off-chain services (core auction protocol as well as the orderbook) to support feature growth and the rapidly changing requirements that come from being an application on a constantly evolving blockchain.

• While your focus will be writing concurrent backend systems in Rust, you will also interact with our Smart Contracts written in Solidity and develop your understanding of auction mechanisms and DeFi protocols

• Participate in our on-call rotation to help ensure the reliability of our production systems (on-call work is additionally compensated)

• Work closely with researchers and the product team to ship features and come up with new solutions for challenging technical problems

• Deliver high-quality code for features from concept until production (including state-of-the-art monitoring of our production systems)

• Give thoughtful and in-depth code reviews of your colleagues’ contributions to our open-source codebase

• You have 5+ years of production experience with systems-level programming languages, with at least 1+ year of hands-on production experience using Rust

• You have practical experience working in web3 (ideally in DeFi and the Ethereum ecosystem)

• You have excellent computer science, programming, and algorithmic skills

• Experience with operating, maintaining, and architecting complex software systems

• You care deeply about the quality, readability, observability, and testability of your code

• You proactively give technical direction to improve performance, prevent issues, optimise data usage, and refactor the codebase

• You are a team player, strong communicator, and gladly share your expertise with others

• You collaborate effectively with a remote-first team on a large, open-source codebase

• Ideally, someone senior who can mentor colleagues and provide direction.

• You are excited to explore and gain experience with Ethereum

• Flexible work environment: Join our hub in Lisbon or work remotely

• Token plan: Have a stake in our mission and shape the future of CoW DAO

• Periodic gatherings: Enjoy opportunities to connect with the rest of the team through regular trips

• Conference allocation: Stay up-to-date with ecosystem advancements using our conference budget

• Learning budget: Use our learning budget to support your higher ambitions

• Hardware budget: Take advantage of a hardware budget for acquiring necessary equipment

• Make an impact: You are joining a startup where you can make a huge difference. Your work matters!

• Flat hierarchies mean fewer processes and bureaucracy - see more of your ideas come to life!

• Flexible work and vacation times: Prioritize work-life balance through our robust flexible work policy and vacation allowance

• Growth: If you're someone who loves taking the initiative and getting things done, CoW offers lots of opportunities for your individual growth

Earn 6.000 USDC or USD with the refer-to-earn program. More details here.

Life within the CoW Protocol is an incredible adventure! We take pride in our collaborative approach, embracing autonomy and fostering a culture of big thinking and continuous growth. We value impact, ownership, simplicity, and team spirit. Plus, we're all about feedback, coming together, and enjoying the journey along the way!