Principal Security Engineer - Blockchain Wallet Infrastructure

Location: Remote - Location: US or EU (remote-first, office optional). Must be in the US, not Canada or in the European Union. France or Paris or as close as possible, always preferred

Compensation: $220K - $300K

Join a stellar team of leaders and experts in blockchain technology, cryptography, and infrastructure to build the backbone of blockchain wallet infrastructure for the next financial era. We are hiring a Principal Security Engineer to lead security design and development across our entire platform. Reporting directly to the CISO, you will set the strategy to protect our high-stakes financial systems, fix vulnerabilities, and keep client wallets safe.

This is a strategic and highly technical role spanning the full security lifecycle. You will make security part of every layer of the stack, from architecture design to incident response. Beyond defense, you will champion secure development practices, mentor engineers, and represent the company's security posture to clients and the wider community.

Responsibilities:

Platform Engineer (Backend)

Location: London, New York

Onsite | Full-time

Compensation: Competitive

Our client is an elite team of builders and a high-growth software development company at the forefront of the fintech and digital asset sectors. The organization is a primary contributor to one of the largest and most active crypto social networks globally, a platform that has generated over $600 million in revenue since early 2024. Operating at the intersection of high-scale social coordination and decentralized finance, the firm is dedicated to redefining the infrastructure of the future.

The organization is seeking a Platform Engineer to join a high-performance environment characterized by talent density and rapid execution. This role is critical in ensuring the security, scalability, and integrity of a platform attracting significant global attention. The successful candidate will bridge the gap between backend engineering and infrastructure security, implementing robust controls across a complex cloud and blockchain ecosystem.

Key Responsibilities

Infrastructure & DevOps Engineer - High-Performance Distributed Systems

Location: Remote - (Europe-friendly time zones preferred)

Compensation: $160K - $300K

We are reengineering blockchain infrastructure from first principles to make global digital markets as precise and dependable as physical systems. Built on a leading high-performance layer-1 network, our platform delivers deterministic execution, guaranteed inclusion, and low-latency performance. We are hiring an Infrastructure & DevOps Engineer to lead critical engineering efforts that drive the performance and scalability of our next-generation distributed systems.

You will join a highly proficient team of core engineers, focusing on Rust systems programming, infrastructure architecture (Kubernetes), and operational scripting. Your work will span the full stack, from bare metal to application interfaces, and will directly support our platform which connects the L1 network with advanced L2 extensions. You will drive high-quality, frequent code shipments, engage in deep architectural discussions, and apply a coherent system design philosophy to advance the industry.

Key Responsibilities:

Staff Backend Engineer

Location: London or New York City

Onsite | Full-time

Compensation: competitive

Our client is a high-performance technology development firm responsible for building and operating the infrastructure behind the world’s largest and most active digital asset launchpads. Processing approximately $1B in daily volume, the platform operates at the bleeding edge of crypto scale, requiring systems designed for ultra-low latency, high throughput, and constant high-concurrency load.

The organization is seeking a Lead Backend Engineer to own the most complex technical challenges across the system. This is a high-stakes, high-impact role within an intense, in-person environment. The team is composed of high-agency builders who value speed, immediate impact, and rigorous engineering judgment. This position is ideal for an engineer who thrives under pressure and is motivated by the opportunity to solve ambiguous, cross-cutting problems that others cannot.

Key Responsibilities

Quantitative Trading & Market Microstructure Specialist - High-Performance DEX

Location: Remote - Global (Preference for candidates based in: Lisbon, Portugal / UAE / Switzerland / Singapore / Hong Kong / Brazil / USA / UK / Spain / Canada / France / Germany / Greece)

Compensation: $180K - $220K

We are building a high-performance blockchain operating system that fundamentally redefines what's possible on Ethereum by prioritizing unparalleled throughput, decentralization, and security. We are now expanding the team for O2, a new, early-stage project: a next-generation decentralized exchange (DEX) running on our modular execution layer. Designed as a Central Limit Order Book (CLOB), our goal is to build the fastest DEX ever constructed, leveraging parallel execution to unlock high-frequency trading efficiency fully on-chain.

You will play a foundational role, leveraging your expertise in market making and quantitative trading to model, simulate, and optimize the market behavior of our core CLOB protocol. This is a highly hands-on role where you will design and test trading strategy logic, build simulation frameworks, and collaborate with engineering and research to inform critical protocol-level design decisions.

Key Responsibilities:

Senior Software Engineer - Developer Tools & SDKs

Location: Remote - US & Americas

Compensation: $ Competitive

We are a fast-growing software company dedicated to supporting and developing an EVM-compatible, open-source, proof-of-stake platform. This public network is engineered for enterprise and Web3 applications, prioritizing speed, security, stability, and sustainability, and is governed by industry-leading organizations. We are seeking an experienced Software Engineer to lead the development of world-class developer tools and SDKs.

You will take the lead on crafting seamless developer experiences, owning the design, build, and maintenance of our open-source SDKs and related tooling. This role requires technical leadership, hands-on coding across multiple languages, and a strong focus on developer empathy. You will work cross-functionally to ensure our tools are intuitive, robust, and aligned with real-world developer needs.

What You'll Be Doing:

Smart Contract Developer - Institutional DeFi Protocol

Location: Remote - US only (preference for onsite/hybrid in LA)

Compensation: $160K - $180K

We are an on-chain financial infrastructure company backed by leading VCs, committed to upgrading financial markets through 24/7 instant settlement. Our first product is an institutional-grade smart contract protocol that facilitates interoperability and liquidity across tokenized financial assets and stablecoins. We are seeking a Smart Contract Developer to join our core engineering team and build the foundational infrastructure that bridges traditional finance (TradFi) and decentralized finance (DeFi).

This is a high-impact, hands-on role where you will design, develop, and deploy highly secure, robust smart contracts for our core protocol. You will architect on-chain logic, optimize gas efficiency, and ensure best-in-class security practices to enable institutional-grade DeFi operations. You will work within a small, senior team, collaborating closely with security auditors, product, and business stakeholders.

Key Responsibilities:

Senior Rust Engineer - On-Chain Security Infrastructure

Location: Remote - Europe

Compensation: $165K - $200K

We are building a Credible Layer—a step-level improvement for on-chain security designed to safeguard the crypto industry and restore credibility after billions were lost to hacks. We are creating an on-chain protocol and off-chain infrastructure that enables protocols to enforce security rules for every transaction. Backed by world-class investors, we are seeking a Senior Rust Engineer to work on bleeding-edge infrastructure at the heart of our mission.

You will play a crucial role in shipping cutting-edge features that extend the EVM (Ethereum Virtual Machine) to enable security rules to be checked after every state transition. This is a high-impact, deeply technical role requiring expertise in performance optimization and low-level systems programming within a collaborative, fast-iteration environment.

Key Responsibilities:

Senior Protocol Engineer - Stablecoin Platform

Location: Remote - US based (Would consider South America/Canada/Europe if can overlap with EST timezones)

Compensation: $170K - $200K

We are a pioneering stablecoin platform providing developers with a superior digital-dollar building block ($\$M$) to create custom, compliant stablecoins in minutes. We are seeking an experienced Senior Protocol Engineer to architect and develop audit-ready smart contracts, helping businesses monetize their digital dollar use cases while maintaining control over their money tech stack.

You will be responsible for the security, performance, and development of our core blockchain protocols. This role requires technical mastery in smart contract design, a commitment to audit readiness, and strong collaboration skills as you work across functional teams (designers, product managers, and developers) to enhance and extend our existing stablecoin products.

Key Responsibilities:

Senior Infrastructure Engineer - Blockchain Wallet Backbone

Location: Remote - United States

Compensation: $180K - $300K

Join a stellar team of leaders and experts in blockchain technology, cryptography, and security. Our client is seeking a Senior Infrastructure Engineer to design, operate, and scale systems at the intersection of blockchain, cybersecurity, and distributed infrastructure, preparing them to meet the demands of a trillion-dollar industry.

This role goes beyond maintenance—you will be an architect, automator, and security expert. You will embed best-in-class DevOps and SRE practices into their workflows, ensuring their services are highly reliable, secure, and cost-efficient. You will collaborate across engineering, product, and security to translate complex requirements into scalable infrastructure.

Key Responsibilities: