Location: European time zone

Remote | Full-time

Compensation: Up to £65 per hour, depending on experience

We are seeking a highly skilled Smart Contract Engineer with a dual proficiency in Solidity and Rust to join our engineering team. In this role, you will be employed by MLabs and subcontracted to work directly on high-impact DeFi protocols for one of our premier clients. Your primary focus will be building and scaling decentralised financial infrastructure on leading Layer 2 networks like Base and Arbitrum. You will move fluidly between writing secure on-chain logic and developing high-performance backend systems or tooling in Rust. This is a role for an engineer who thrives on the "security-first" mindset required for DeFi, ensuring that protocol architecture remains robust against adversarial environments while maintaining peak gas efficiency.

Key Responsibilities

• Architect & Develop: Design and implement robust, production-grade smart contracts in Solidity for deployment on L2s like Base and Arbitrum.
• Systems Engineering: Build high-performance backend services, tooling, or blockchain components using Rust to support on-chain logic.
• DeFi Logic: Develop complex on-chain financial logic including AMMs, lending/borrowing mechanics, staking protocols, or yield-generating products.
• Optimization: Perform deep-dive gas optimizations and performance tuning for both smart contracts and Rust-based infrastructure.
• Security & Risk: Apply rigorous security best practices to protect against common DeFi attack vectors (reentrancy, oracle manipulation, etc.) and participate in internal code reviews.

Core Technical Skills (Must-Have):

• Solidity Expertise: Proven track record of writing, testing, and deploying production-level smart contracts. You should be intimately familiar with common design patterns, security best practices, and upgradeable contract architectures.
• EVM Deep Dive: Comprehensive understanding of the EVM, gas optimization strategies, and the nuances of deploying to L2s (Base/Arbitrum preferred).
• Rust Systems Programming: Professional experience building backend services, tooling, or blockchain components in Rust. You should be comfortable working across both the smart contract layer and the systems/backend layer.
• DeFi Domain Knowledge: Prior experience in Decentralized Finance is a priority. We are looking for candidates who have worked on DEXs (AMMs/Order books), Lending/Borrowing protocols, Staking/Restaking, or complex Tokenomics.

Security & Architecture:

• Adversarial Reasoning: Ability to identify and mitigate common DeFi attack vectors (e.g., reentrancy, oracle manipulation, sandwich attacks).
• Architectural Trade-offs: Deep understanding of the pros and cons of on-chain vs. off-chain logic.
• Performance: Experience with performance-sensitive or concurrent systems is a significant bonus.

Benefits

• High-Impact Projects: Work on the core infrastructure of leading DeFi protocols at the forefront of the Web3 space.
• Expert Collaboration: Join MLabs’ network of world-class functional programming and blockchain experts while working closely with innovative client teams.
• Compensation: Up to £65 per hour, depending on experience
• Remote & Flexible: Benefit from a culture that values autonomy and output over hours at a desk.
• Professional Growth: Gain exposure to diverse tech stacks (Solidity, Rust, EVM, L2s) and sophisticated financial risk models.