# Senior Fullstack Engineer > MLabs · Poland (Remote) · — · Posted 2026-07-23 **Workplace:** remote **Department:** RLL ## Description **Location: Remote - Europe preferred, must be able to work European hours** **Remote | Full-time** **Compensation: $120K - $150K** Our 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 Responsibilities** **Frontend Development & Performance** - Build and maintain the React-based trading user interface. - Implement dynamic, interactive interfaces for real-time data, including live order book updates, price feeds, and trade executions via WebSockets. - Own component architecture, state management, and responsive design. - Optimize rendering, minimize load times, and ensure smooth, low-latency interactions under heavy data loads. - Collaborate closely with product and design teams to translate complex requirements into intuitive user interfaces. **Backend Development & Data Infrastructure** - Design and maintain TypeScript services, including REST APIs, WebSocket servers, and background services. - Design and deliver event-driven pipelines that ingest and process pricing and account data. - Own REST and WebSocket API contracts (OpenAPI / AsyncAPI specs), ensure smooth data flow between frontend and backend, and maintain API documentation. - Interact with on-chain data, index blockchain events, and bridge smart contracts with off-chain services. **Quality, Security & Collaboration** - Develop and maintain comprehensive unit, integration, and end-to-end tests across frontend and backend systems. - Uphold continuous integration (CI) quality gates and rigorous code review standards. - Work closely with cross-functional teams, including product, design, and quantitative specialists. ## Requirements **Minimum Qualifications** - **Experience:** 6+ years of professional experience in fullstack software engineering. - **Core Tech Stack:** Deep expertise in TypeScript across both frontend and backend development. - **Frontend:** 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 runtimes. - **Databases & Caching:** Experience with relational databases (PostgreSQL) and ORMs (Prisma or equivalent), along with familiarity with Redis or similar caching and pub/sub systems. - **Engineering Standards:** Commitment to writing clean, maintainable code, backed by solid experience in unit, integration, and end-to-end testing methodologies. - **Communication:** Clear and effective communication skills suitable for a fully remote, distributed, cross-functional team environment. **Preferred Qualifications** - **Domain Experience:** 8+ years of fullstack experience, ideally within fintech, trading platforms, or real-time data applications. - **Systems Languages:** Experience with Rust or C++ for building high-scalability web services. - **Web3 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 logging. **Ideal Profile** - Comfortable working in a agile, focused team navigating high complexity and evolving requirements. - Motivated by the opportunity to shape modern financial technology infrastructure. - Thrives in environments utilizing rapid prototyping and iterative development cycles. ## Benefits - **100% Remote:** Fully remote work arrangement with global flexibility. - **Competitive Compensation:** Industry-aligned salary package reflecting senior-level experience. - **Professional Growth:** Opportunity to solve complex technical challenges at the cutting edge of finance and web technology **Due 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. This information is managed securely in accordance with MLabs Ltd’s Privacy Policy and Information Security Policy, and in compliance with applicable data protection laws. Your data may be shared only with clients and trusted partners where necessary for recruitment purposes. You may request the deletion of your data or withdraw your consent at any time by contacting legal@mlabs.city. ## Apply [Apply at MLabs](https://apply.workable.com/mlabs/j/00D4B5D42A/apply) --- Powered by [Workable](https://www.workable.com)