Location: Remote - Europe preferred, must be able to work European hoursRemote | Full-timeCompensation: $120K - $150KOur client is a dynamic, forward-thinking, fully remote organization with an ambitious roadmap and a strong commitment to engineering excellence.Seeking a Senior Fullstack Engineer to work at the intersection of frontend and backend development. In this role, the engineer will build and maintain both a React-based trading user interface and the TypeScript backend services that power high-performance trading platforms. The position involves full feature ownership—from crafting responsive, real-time interfaces to designing the APIs, data pipelines, and indexing solutions that feed them.The ideal candidate possesses a strong passion for trading, engineering rigor, security, and velocity, backed by over six years of professional experience and a dedication to code quality and state-of-the-art software testing practices.Key ResponsibilitiesFrontend Development & PerformanceBuild and maintain the React-based trading user interfaceImplement dynamic, interactive interfaces for real-time data, including live order book updates, price feeds, and trade executions via WebSocketsOwn component architecture, state management, and responsive designOptimize rendering, minimize load times, and ensure smooth, low-latency interactions under heavy data loadsCollaborate closely with product and design teams to translate complex requirements into intuitive user interfacesBackend Development & Data InfrastructureDesign and maintain TypeScript services, including REST APIs, WebSocket servers, and background servicesDesign and deliver event-driven pipelines that ingest and process pricing and account dataOwn REST and WebSocket API contracts (OpenAPI / AsyncAPI specs), ensure smooth data flow between frontend and backend, and maintain API documentationInteract with on-chain data, index blockchain events, and bridge smart contracts with off-chain servicesQuality, Security & CollaborationDevelop and maintain comprehensive unit, integration, and end-to-end tests across frontend and backend systemsUphold continuous integration (CI) quality gates and rigorous code review standardsWork closely with cross-functional teams, including product, design, and quantitative specialistsRequirementsMinimum QualificationsExperience: 6+ years of professional experience in fullstack software engineeringCore Tech Stack: Deep expertise in TypeScript across both frontend and backend developmentFrontend: Strong experience with React and modern state management patterns (hooks, context, or equivalent)Backend & APIs: Experience building and consuming REST APIs and WebSocket real-time data protocols; proficiency with Node.js or Bun server-side runtimesDatabases & Caching: Experience with relational databases (PostgreSQL) and ORMs (Prisma or equivalent), along with familiarity with Redis or similar caching and pub/sub systemsEngineering Standards: Commitment to writing clean, maintainable code, backed by solid experience in unit, integration, and end-to-end testing methodologiesCommunication: Clear and effective communication skills suitable for a fully remote, distributed, cross-functional team environmentPreferred QualificationsDomain Experience: 8+ years of fullstack experience, ideally within fintech, trading platforms, or real-time data applicationsSystems Languages: Experience with Rust or C++ for building high-scalability web servicesWeb3 Integration: Familiarity with the Web3 frontend stack (e.g., ethers.js, viem, client-side wallet integrations)Architecture: Knowledge of event-driven and messaging architectures (Kafka, Google Pub/Sub, or similar)Observability: Experience with observability tools such as Datadog, Prometheus, or Winston loggingIdeal ProfileComfortable working in a agile, focused team navigating high complexity and evolving requirementsMotivated by the opportunity to shape modern financial technology infrastructureThrives in environments utilizing rapid prototyping and iterative development cyclesBenefits100% Remote: Fully remote work arrangement with global flexibilityCompetitive Compensation: Industry-aligned salary package reflecting senior-level experienceProfessional Growth: Opportunity to solve complex technical challenges at the cutting edge of finance and web technologyDue to the high volume of applications we anticipate, we regret that we are unable to provide individual feedback to all candidates. If you do not hear back from us within 4 weeks of your application, please assume that you have not been successful on this occasion. We genuinely appreciate your interest and wish you the best in your job search.Commitment to Equality and Accessibility:At MLabs, we are committed to offer equal opportunities to all candidates. We ensure no discrimination, accessible job adverts, and providing information in accessible formats. Our goal is to foster a diverse, inclusive workplace with equal opportunities for all. If you need any reasonable adjustments during any part of the hiring process or you would like to see the job-advert in an accessible format please let us know at the earliest opportunity by emailing human-resources@mlabs.city.MLabs Ltd collects and processes the personal information you provide such as your contact details, work history, resume, and other relevant data for recruitment purposes only. 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