About Symbiotic

At Symbiotic, we are building a permissionless shared security primitive that empowers network builders to shape and personalise their unique restaking implementation. Our goal is to minimise risks while maximising freedom for all you wonderful builders of crypto infrastructure networks. We have a robust developer-centric proposition and we can’t wait to share it with everyone.

You can find more information about what we’re building and how we’re doing it in our docs.

Our People

We’re a tight-knit team of experienced individuals at the forefront of crypto infrastructure. Our backgrounds range from security auditing and smart contract development to node operation, and we’re supported by Paradigm and CyberFund.

We’re on the hunt for talented professionals to join our mission and strengthen our awesome team.

The Role

We are seeking a Senior Smart Contract Engineer to work on our existing smart contract codebase, including core contracts, core extensions, and middleware SDK, as well as develop new upcoming modules.

What You’ll Do

• Work at the intersection of blockchain protocols and smart contracts, contributing to the design and development of EVM-based systems
• Write, optimize, and audit smart contracts in Solidity, with a focus on performance, clarity, and security
• Build and experiment with staking, DeFi, and other protocol-level primitives
• Leverage tools like Foundry and Hardhat for development, testing, and deployment
• Conduct and support security audits, addressing vulnerabilities and integrating best practices
• Collaborate closely with protocol engineers to support integrations across L1 and L2 chains
• Work with web3 libraries like ethers.js, viem, and web3.py for off-chain contract interactions
• Occasionally contribute to related tooling and scripting in Python and TypeScript

Who You Are

• Strong understanding of Ethereum L1/L2 architecture and PoS mechanisms
• Familiar with blockchain primitives such as consensus algorithms and cryptography
• Deep knowledge of EVM internals: execution flow, memory/storage models, gas mechanics, and precompiles
• Expert in Solidity, with exposure to Yul, Vyper, or Huff (a plus)
• Solid grasp of DeFi concepts: DEXes, lending protocols, stablecoins, and staking mechanisms
• Proficient with Foundry, Hardhat, and comfortable working with ethers.js, web3.js, viem, or web3.py
• Strong security mindset, familiar with common attack vectors and the auditing process
• Practical coding experience in Python and JavaScript/TypeScript

Nice to Have

• Experience in compilers development
• Experience in Rust, Go, C/C++
• Experience in protocol development such as L1, L2
• OP stack, Arbitrum knowledge
• Experience with ZK on EVM

As a Senior Blockchain Engineer, you will be responsible for designing, developing, and optimizing smart contracts and blockchain infrastructure for our platform. You will work closely with the CPO and product teams, and other engineers to deliver innovative and secure solutions within the DeFi ecosystem.

Technical Leadership & Architecture

• Design and optimize blockchain product architecture with a focus on scalability, security, and performance.
• Develop and improve cross-chain interoperability solutions (cross-chain swaps, bridges, and interconnectivity).
• Lead the development, auditing, and integration of smart contracts within decentralized protocols.
• Design and develop efficient algorithms with a focus on gas optimization.
• Conduct technical research, proof-of-concept (PoC) experiments, and implement best practices in blockchain development.

Team Collaboration & Development Process

• Work closely with product and engineering teams to design optimal blockchain solutions.
• Define and implement effective CI/CD processes for blockchain development.
• Perform code reviews, mentor developers, and enforce best practices in blockchain engineering.
• Collaborate with auditors and cross-functional teams to ensure successful product launches.

Technical Excellence & Innovation

• Continuously monitor emerging blockchain, Web3, and crypto technologies.
• Analyze and address potential attack vectors, ensuring security best practices.
• Optimize blockchain infrastructure to improve performance and reduce transaction costs.
• Engage with blockchain communities, contribute to open-source initiatives, and participate in ecosystem discussions.

Experience Required

• 7+ years of software development experience, with at least 3+ years in blockchain engineering.
• Deep understanding of blockchain ecosystems, smart contracts (Solidity, Yul, EVM), and decentralized applications (dApps).
• Hands-on experience with Ethereum, Layer 2 solutions (Optimistic & ZK Rollups), and cross-chain protocols (atomic swaps, bridges, etc.).
• Proven track record in technical leadership, architectural decision-making, and mentoring development teams.
• Strong background in blockchain security and experience with smart contract audits.

Skills

• Proficiency in Solidity, Yul, Rust, TypeScript.
• Experience with smart contract development and deployment frameworks (Foundry, Hardhat).
• Understanding of DeFi protocols, AMMs, liquidity pools, and oracle integrations.
• Expertise in blockchain security principles and smart contract auditing methodologies.
• Experience in building high-performance distributed systems.

Mindset

• “Get Stuff Done” Mentality – ability to execute quickly while maintaining security and quality.
• Strong problem-solving skills and ability to navigate the constant innovations of the crypto market.
• Passion for research, innovation, and staying ahead of blockchain industry trends.
• Commitment to decentralization and open-source development.

Performance Measurement

• Speed and efficiency of feature deployments and updates.
• Code quality and successful security audit results.
• Impact on system architecture and scalability.
• Contribution to team growth and technical expertise.

Why you’ll love working with us

• Join a young, creative team in a fast-paced and supportive environment
• We’re open to new ideas — if you’ve got a vision, pitch it and make it happen
• Enjoy competitive pay that matches your skills and experience
• Be part of a company that’s shaping the future of DeFi
• Take time when you need it — we offer unlimited vacation days
• Get fully compensated for your work gear — we’ll set you up for success
• Travel with us! We host an annual team retreat at a top international location

About the Company:  Shardeum is building a layer 1, EVM-based, linearly scalable, smart contract platform that provides low gas fees forever while maintaining true decentralization and solid security through dynamic state sharding. Shardeum aims to be a chain capable of onboarding over a billion people to the crypto revolution, while also democratizing accessibility to decentralization. Shardeum’s mission is supported by prominent Venture Capitalists in the blockchain space, and we are on track to become one of the most widely used and well known smart contract platforms in blockchain history.We encourage you to browse our website, Whitepaper, Discord and YouTube channel to learn more about the project. You can even try downloading our validator software and joining our Testnet. We encourage people of all backgrounds to apply. Your talent and potential is what matters most to us. Shardeum is committed to creating an inclusive culture.About The Role: The Engineering team at Shardeum is responsible for delivering the Shardeum Mainnet and developing critical components such as the smart contract platform, consensus layer, and protocol layer. As part of this team, the Senior Software Engineer - Testing Tools & Strategy will play a key role in ensuring the quality, reliability, and performance of Shardeum’s decentralized platform through robust test automation, debugging, and validation processes. This role is ideal for engineers who have a passion for test automation, load testing, and identifying root causes of bugs to enhance blockchain performance and scalability. If you’re excited about solving unique challenges in the Web3 space and driving innovation in blockchain testing methodologies, we want to hear from you! What You'll Be Doing:

Analyze bug tickets, debug code, and identify the root cause of errors across the Shardeum platform. Design, develop, and maintain test automation frameworks and reusable test scripts to validate core functionality, including nodes, consensus mechanisms, smart contracts, and blockchain transactions. Utilize cutting edge AI tools to make testing faster and more efficient (Cursor, Github Copilot, Windsurf, Cline, etc..) Develop and execute load testing scripts to validate system performance under high transaction loads and varying node configurations. Create comprehensive test coverage through functional, integration, system, and regression testing while optimizing test suites and identifying performance bottlenecks. Develop end-to-end (E2E) test cases for complex workflows, ensuring reliability of consensus protocols and smart contract execution. Collaborate closely with development teams to integrate testing into CI/CD pipelines, improve testing workflows, and troubleshoot dependency failures. Build and maintain internal tools to improve developer experience, productivity, and test efficiency. Troubleshoot highly complex automated testing failures using industry-standard frameworks and custom tools, working with developers and backend partners to triage issues and improve E2E reliability. Develop monitoring tools and utilities to track blockchain-specific performance metrics and test results. Participate actively in agile ceremonies, including sprint planning, stand-ups, and retrospectives, to drive testing best practices. Continuously research and adopt innovative tools, frameworks, and testing methodologies to improve quality, scalability, and efficiency of testing processes.

What We're Looking For:

5+ years of experience in Software Engineering experience with a focus on testing. Proficiency in programming languages like TypeScript/JavaScript and Node.js, with the ability to develop robust and reusable test scripts. Ability/desire to write Unit Tests in TypeScript/JavaScript and Node.js Proven ability to analyze and debug complex codebases, troubleshoot multi-tier web architecture issues, and identify root causes of failures. Experience integrating automated tests into CI/CD workflows (e.g., GitHub Actions, Jenkins). Expertise in defining and implementing release, regression, and smoke testing strategies for large, multi-team applications. Experience with white-box testing methodologies to ensure deep validation of internal components. Strong problem-solving and critical-thinking skills, particularly in analyzing blockchain-specific issues. You have a tester mindset, are curious, and excel at designing innovative and interesting test scenarios. You are creative in applying proven tools/test frameworks as well as crafting new solutions to challenging problems. Knowledge of Agile/Scrum methodologies and the software development lifecycle. Excellent verbal and written communication skills for clear bug reporting and collaboration across teams.

We'd Love If You Have:

Experience with testing decentralized applications (dApps), consensus protocols, or blockchain platforms. Experience in running nodes within blockchain networks and monitoring performance metrics. Familiarity with blockchain tools and frameworks (e.g., Web3.js, Hardhat, Truffle). Hands-on knowledge and experience with AI tools (Cursor, Github Copilot, Windsurf, Cline, etc...), and the ability to demonstrate how you utilize them in your day to day. Contributions to open-source projects related to testing, automation, or blockchain. A passion for emerging technologies, including Web3, AI, and distributed systems. Experience using or contributing to the Shardeum open-source repos. Familiarity with blockchain performance benchmarks and profiling tools. Knowledge of the Bitcoin and Ethereum whitepapers.

We are building the infrastructure for Web 3.0. 

Apply Now: