Senior Full Stack Developer (React / Node.js )

🏢 Summary: Senior Fullstack Engineer role focused on building modern, scalable web applications using React and Node.js, with strong emphasis on frontend development. The position covers the full application stack, including backend services, API design, and data management. You will collaborate with cross-functional teams to deliver high-quality, accessible, and high-performance digital products. 🗂️ Requirements: Strong commercial experience with React, Strong commercial experience with Node.js, Experience with React Router, Experience with TanStack Query, Experience integrating Headless CMS (preferably Contentful), Understanding of API design principles, Experience with PostgreSQL, Experience with Redis, Experience with Vitest, Experience with Playwright, Knowledge of WCAG accessibility standards, Experience with performance optimisation, Ability to work across full software development lifecycle 📃 Skills: React, Node.js, TypeScript, Fastify, PostgreSQL, Redis, React Router, TanStack Query, Contentful, Vitest, Playwright, WCAG, SAP Gigya, Salesforce 🏢 Description: Senior Fullstack Engineer (React & Node.js) About the Role We are looking for a Senior Fullstack Engineer to join a product team building modern, scalable web applications and digital experiences. You will work across the entire application stack, from user-facing interfaces to backend services and integrations. The role has a strong focus on frontend engineering while also involving backend development, API design, and data management. You will collaborate closely with product, design, and engineering teams to deliver high-quality, accessible, and performant applications. Responsibilities Develop and maintain modern web applications using React, Node.js, and TypeScript. Build scalable and reusable UI components integrated with a design system. Develop and maintain backend services and APIs using Node.js and Fastify. Integrate applications with CMS platforms and third-party services. Work with PostgreSQL and Redis to support application functionality and performance. Write and maintain automated tests, including unit and end-to-end tests. Ensure high standards of accessibility, performance, and code quality. Participate in architectural discussions and contribute to engineering best practices. Requirements Strong commercial experience in fullstack development using React and Node.js. Solid experience with modern frontend technologies, including React Router and TanStack Query. Experience integrating with Headless CMS platforms, preferably Contentful. Good understanding of API design and backend development principles. Experience with PostgreSQL and Redis. Experience with automated testing frameworks such as Vitest and Playwright. Strong understanding of accessibility standards (WCAG) and performance optimisation. Ability to work across the entire software development lifecycle in a product-oriented environment. Nice to Have Experience with authentication and identity platforms such as SAP Gigya. Experience integrating Salesforce products or loyalty platforms. Experience in highly scalable, customer-facing digital products. Experience working in agile, cross-functional product teams.

🏢 Summary: Fullstack Developer role focused on building and maintaining backend services in Node.js and frontend applications in React/Next.js, with occasional involvement in smart contract development. The position involves working with databases, APIs, and collaborating across backend and blockchain teams in an onsite environment. The offer is targeted at senior-level engineers with strong production experience. 🗂️ Requirements: Strong Node.js/NestJS backend experience, Minimum 5 years of backend development experience, Minimum 2 years maintaining production applications, Strong React and TypeScript skills, Experience with database and API integration, Ability to work onsite in Warsaw (100%), English level B2 or higher 📃 Skills: Node.js, NestJS, Express, React, Next.js, TypeScript, PostgreSQL, MongoDB, API, EVM, SVM 🏢 Description: About BlockyDevs We build end-to-end applications combining fintech-grade reliability with Web3 innovation. Your Role As a Fullstack Developer, you’ll primarily work with Node.js on the backend, React on the frontend, and occasionally contribute to smart contract development. Responsibilities Develop backend services with *Node.js (NestJS/Express)** Build frontend apps with *React/Next.js + TypeScript** Work with databases (PostgreSQL, MongoDB) and APIs Occasionally contribute to smart contracts (EVM/SVM) Collaborate with design, backend, and blockchain teams Requirements Strong backend skills in Node.js/NestJS At least 5 years of experience in backend applications At least 2 years of experience in maintaining production applications Solid frontend skills in React + TypeScript Database and API integration knowledge Experience mentoring mid/junior developers English at least B2 level Ability to work 100% onsite from our office near Metro Plac Wilsona, Warsaw Nice-to-have Microservices and cloud deployment experience Web3 integrations knowledge Rates (B2B/Freelance) Senior: 120 - 180 PLN/h Recruitment Process 1. Intro Call (30 min) – Quick chat about your experience, expectations, and our projects. 2. Technical Interview / Task – Backend (Node.js) and frontend (React) focus, with some discussion of smart contracts. 3. Final Meeting – Culture/fit + project discussion. 4. Offer – Fast decision if it’s a match. 5. Process usually takes 2–3 weeks . 6. Feedback after each stage within a few days

🏢 Summary: Full-time Senior Full Stack Developer role focused on building scalable, data-driven platforms for financial and enterprise sectors using Node.js and React. The position involves designing microservices, developing RESTful APIs, and creating responsive front-end applications in a hybrid work model (Warsaw). 🗂️ Requirements: 5+ years experience as Senior Full Stack Developer, Strong expertise in Node.js, Strong expertise in React, Experience with Express.js, Experience building RESTful or GraphQL APIs, Knowledge of OAuth and JWT authentication, Proficiency in Redux, HTML5, CSS3, ES6+, Experience with Vite, Webpack or Babel, Experience with MySQL or PostgreSQL, Experience with AWS, Azure or GCP, Experience with Docker and Kubernetes, Proficiency with Git 📃 Skills: Node.js, React, Express.js, GraphQL, REST, OAuth, JWT, Redux, HTML5, CSS3, JavaScript, ES6, Vite, Webpack, Babel, MySQL, PostgreSQL, AWS, Azure, GCP, Docker, Kubernetes, Git, SQL, MongoDB, CI/CD 🏢 Description: Senior Full Stack Developer (Node.js + React) 💰 Salary: 23,000-24,800 PLN/Month 💻 Warsaw, Poland (Hybrid - 3 days in office, 2 days remote) 🕦 Full-time ☑️ B2B or CoE We’re looking for a Senior Full-Stack Developer to join a fast-growing international tech company focused on building modern, data-driven platforms that power digital transformation in the financial and enterprise sectors. Requirements: 5+ years of experience as a Senior Full Stack Developer with significant expertise in Node.js and React. Strong experience in building server-side applications using Node.js and Express.js. Hands-on experience with API development and integration, particularly with GraphQL or RESTful services. Strong knowledge of authentication and authorization mechanisms (OAuth, JWT, session-based). Front-end proficiency in React.js, Redux, HTML5, CSS3, and modern JavaScript (ES6+). Familiarity with front-end build tools such as Vite, Webpack, and Babel. Strong experience with databases such as MySQL and  PostgreSQL. Experience with cloud platforms (AWS, Azure, or GCP), as well as containerization and orchestration tools such as Docker and Kubernetes. Strong experience using Git and version control systems. Proficiency in English (both written and spoken). Key Responsibilities: Design, build, and maintain scalable, high-performance server-side applications and RESTful APIs using Node.js and Express.js. Develop and maintain interactive, responsive user interfaces using React.js, Redux, and modern JavaScript (ES6+). Lead the design and implementation of scalable architectures and microservices. Work closely with database engineers to design efficient schemas and manage data interactions using SQL databases or MongoDB. Ensure reliable deployments and smooth release of updates using CI/CD pipelines and Docker. Write unit and integration tests and optimize performance to ensure high-quality code. Collaborate closely with cross-functional teams to define and implement technical solutions. Improve system performance, reliability, and long-term maintainability through optimization and best practices. Get to know DevsData: We are a technology consulting company and a recruitment agency, delivering software solutions to clients from Europe and the US. We work 100% remotely, in an international team, including people from Asia, London, or San Francisco. We employ people with experience in international corporations as well as students of the best technical and business universities. Find out more: https://devsdata.com/

🏢 Summary: Senior Full Stack Developer role focused on architecting and delivering high-performance web applications using React and Node.js. The position involves leading system design, building scalable front-end and back-end solutions, and overseeing cloud-based deployments and DevOps processes. The role includes technical ownership of microservices, APIs, databases, and application performance in a hybrid Warsaw-based setup. 🗂️ Requirements: 7+ years full stack development experience, 2+ years in senior or technical lead role, Expert-level React.js with Hooks and Redux, Advanced JavaScript ES6+ proficiency, Strong Node.js and Express.js experience, Experience designing REST or GraphQL APIs, Experience with OAuth, JWT, sessions, RBAC, Database design and optimization with PostgreSQL, MySQL, or MongoDB, Hands-on Docker experience, Experience with AWS, Azure, or GCP, CI/CD pipeline management experience, Proficiency with Git workflows, Bachelor’s or Master’s in Computer Science or related field 📃 Skills: React, Redux, JavaScript, HTML5, CSS3, Node.js, Express, GraphQL, REST, OAuth, JWT, RBAC, PostgreSQL, MySQL, MongoDB, Docker, Kubernetes, AWS, Azure, GCP, Git, CI/CD, Webpack, Babel, Vite 🏢 Description: 🧩 About the Company Our client is a rapidly growing US-based technology firm with global operations. With a strong commitment to innovation and quality engineering, the company is building a new engineering hub in Warsaw. This is your opportunity to join a high-performing team and play a pivotal role in developing next-generation digital solutions for the private capital markets. 📍 Location & Setup Start remotely and transition to a hybrid model based in Warsaw (3 days/week in the office in the coming months). 🧠 The Role: Senior Full Stack Developer (React & Node.js) We’re looking for an expert-level Senior Full Stack Developer with at least 7 years of professional experience in designing, architecting, and delivering high-performance web applications. You will take ownership of complex technical challenges across both the front-end and back-end, drive architectural decisions, and provide technical leadership and mentorship within the software development lifecycle. 🔧 Key Responsibilities Technical Leadership: Architect and develop scalable, responsive UIs with React.js, Redux, and modern JavaScript (ES6+). System Design: Design, build, and scale advanced server-side applications, microservices architecture, and RESTful/GraphQL APIs with Node.js and Express. Data Architecture: Lead database design, optimization, and integration strategies (PostgreSQL, MySQL, or MongoDB). Quality Assurance: Define testing strategies, write robust unit/integration tests, and establish efficient debugging protocols for the team. DevOps & Deployment: Oversee and optimize CI/CD pipelines, containerization using Docker, and cloud deployments. Agile Mentorship: Lead agile collaboration with product managers, designers, and engineers, while mentoring mid-level and junior developers. Performance: Proactively monitor system performance, identify bottlenecks, and maintain high-availability production-grade applications. Standards: Establish and maintain comprehensive technical documentation and coding standards. 📌 What We’re Looking For Front-End: Expert-level experience with React.js, Hooks, Redux, and complex component-based architecture. Deep mastery of HTML5, CSS3, and ES6+. Advanced configuration and optimization experience with build tools like Webpack, Babel, or Vite. Back-End: Senior-level proficiency in Node.js & Express.js for enterprise applications. Extensive API design and architecture experience (GraphQL highly preferred, alongside REST). Deep understanding and implementation experience with advanced security and authentication protocols: OAuth, JWT, sessions, and RBAC. Databases & DevOps: Proven experience in scaling and optimizing relational and non-relational databases (PostgreSQL, MySQL, or MongoDB). Solid hands-on experience with Docker; Kubernetes experience is highly advantageous. Demonstrated experience designing and deploying applications on cloud platforms (AWS, Azure, or GCP). Advanced proficiency with Git workflows and driving Agile/Scrum methodologies. 🎓 Qualifications Bachelor’s or Master’s in Computer Science or a related field. 7+ years of hands-on experience in full stack development. 2+ years of experience in a senior or technical lead capacity. Proven track record of architecting, deploying, and maintaining high-traffic production applications. 💡 Soft Skills Strategic, analytical thinker and highly effective problem-solver. Strong technical leadership, team collaboration, and cross-functional communication skills. Self-motivated with excellent time management and the ability to drive projects autonomously. Passion for continuous learning, adopting new technologies, and sharing knowledge with the team. 🎁 What’s Offered Competitive salary up to $6,200 USD/month. Hybrid remote role with 3 days form office in the heart of Warsaw Generous Paid Time Off (PTO). Comprehensive full benefits package. The unique chance to shape the technical foundation of a new engineering hub and lead high-impact projects. A supportive, innovation-driven work environment that values technical excellence.

🏢 Summary: Hybrid Team Lead FullStack role focused on building and scaling high-performance web applications using React and Node.js, while leading a development team. The position combines hands-on front-end and back-end development with architectural design, API development, and cloud-based deployments. You will drive technical excellence across the full software development lifecycle in an international R&D environment. 🗂️ Requirements: 7+ years full-stack development experience with React and Node.js, 2+ years experience in team leadership or senior developer role, Expertise in React.js, Redux, React Hooks, Strong knowledge of HTML5, CSS3, JavaScript (ES6+), Proficiency in Node.js and Express.js, Experience designing RESTful APIs or GraphQL APIs, Knowledge of OAuth, JWT or session-based authentication, Experience with PostgreSQL or MySQL, Experience with AWS, Azure or GCP, Experience with Docker and CI/CD pipelines 📃 Skills: React, Redux, JavaScript, HTML5, CSS3, Node.js, Express, GraphQL, REST, OAuth, JWT, PostgreSQL, MySQL, AWS, Azure, GCP, Docker, Kubernetes, CI/CD, Webpack, Babel, Vite 🏢 Description: Team Lead FullStack (Node.js, React) IT · Warsaw (City Center) · Hybrid About the Client Our Client is a fast-growing, international technology company that provides innovative digital solutions for the global market. They are currently expanding and developing their R&D center in Warsaw. They are a leader in AI-powered enterprise operations, delivering digital solutions and consulting services that drive value and transform businesses. They specialize in using advanced technology to streamline operations, improve efficiency, and unlock new revenue opportunities, particularly within the private capital markets. With over a decade of experience supporting high-growth companies, they bring deep domain expertise and a proven ability to turn technology into a strategic advantage. Role Overview We are seeking a highly skilled Full Stack Team Lead with expertise in React and Node.js to lead our dynamic team. The ideal candidate will have over 7 years of experience in designing and building high-performance web applications, along with demonstrated leadership experience. You will lead a team of developers, working on both front-end and back-end development, contributing to every stage of the software development lifecycle, and mentoring junior team members. Key Responsibilities Team Leadership & Mentorship: Lead and mentor a team of software engineers, fostering a collaborative and high-performance environment. Provide technical guidance, conduct code reviews, and support professional development. Front-End Development: Build and maintain interactive and responsive user interfaces using React.js, Redux, and modern JavaScript (ES6+). Back-End Development: Develop robust, scalable server-side applications and RESTful APIs using Node.js and Express. Application Architecture & Integration: Design and implement scalable architectures and microservices that meet business needs, ensuring best practices are followed across the team. Collaborate with database engineers to design efficient database schemas and manage data interactions using MongoDB or SQL databases. Deployment & Testing: Manage deployments and ensure seamless delivery of updates using CI/CD pipelines and containerization tools like Docker. Ensure high-quality code by writing unit and integration tests, performing debugging, and optimizing application performance. Collaboration & Documentation: Work closely with designers, product managers, and other developers to deliver innovative and user-centric solutions. Create and maintain technical documentation for applications, APIs, and architectural decisions, ensuring team adherence to documentation standards. Requirements & Qualifications Experience & Education: 7+ years of professional experience in full-stack development with React and Node.js. 2+ years of experience in a team lead or senior leadership role, guiding and mentoring other developers. A Bachelor's degree in Computer Science or equivalent is preferred. Front-End Stack: Expertise in React.js, Redux, React Hooks, and component-based architecture. Strong knowledge of HTML5, CSS3, and modern JavaScript (ES6+). Familiarity with front-end tools like Webpack, Babel, or Vite. Back-End Stack: Proficiency in Node.js and Express.js for building server-side applications. Experience with API design and integration, including GraphQL (preferred) or RESTful services. Knowledge of authentication mechanisms such as OAuth, JWT, and session-based authentication. Database & DevOps: Hands-on experience with databases such as PostgreSQL or MySQL. Experience with cloud platforms such as AWS, Azure, or GCP. Familiarity with containerization tools like Docker and orchestration tools like Kubernetes is a plus. Soft Skills: Strong problem-solving and analytical skills. Excellent communication and collaboration abilities, with a proven ability to lead and motivate a team. Eagerness to stay updated on emerging technologies and trends, and to drive continuous improvement within the team. What Is Offered Compensation: Monthly compensation up to 9,000 USD gross . Contract Type: Employment Contract (Umowa o Pracę) ONLY . Please note that there is strictly no B2B option available for this position. Work Model: Hybrid (3 days working from the office located in the center of Warsaw, 2 days working from home). Stability: Long-term cooperation with a stable, international organization. Culture: We value creative problem solvers who learn fast, work well in an open and diverse environment, and enjoy pushing the bar for success ever higher. We do work hard, but we also choose to have fun while doing it.

🏢 Summary: Opportunity for a Senior Front-End Developer to modernize and scale an existing web interface using React and Next.js. The role focuses on building high-quality, responsive UI components, integrating with backend services, and driving front-end architecture and best practices. You will collaborate with backend and data teams while ensuring performance, scalability, and code quality. 🗂️ Requirements: Minimum 5 years of hands-on experience with React and Next.js, Strong proficiency in JavaScript and TypeScript, Strong knowledge of HTML and CSS, Experience with RESTful APIs integration, Understanding of modern front-end architecture and design patterns, Experience with front-end testing frameworks, Experience with build tools, Ability to troubleshoot and resolve UI and performance issues 📃 Skills: React, Next.js, JavaScript, TypeScript, HTML, CSS, REST, gRPC-Web, CI/CD, Testing 🏢 Description: Senior Front-End Developer (React / Next.js) We are looking for a Front-End Developer to join a technology-focused team working on modern web applications. This role will play a key part in transforming an existing user interface into a modern, scalable front-end built with React and Next.js. You will be responsible for delivering responsive, high-quality user interfaces and contributing to the long-term evolution of the UI platform. The position involves close collaboration with backend and data teams, as well as ownership of front-end standards and best practices within the team. Responsibilities Redesign and modernize an existing web interface using React and Next.js Build reusable, maintainable UI components with TypeScript Act as a front-end subject matter expert, supporting ongoing improvements to usability and performance Integrate front-end applications with backend services via REST APIs (gRPC-Web knowledge is a plus) Identify, troubleshoot, and resolve UI and performance issues Contribute to code reviews, technical discussions, and CI/CD processes Ensure high code quality through testing, documentation, and adherence to best practices Required Skills & Experience Min. 5 years of hands-on experience with React and Next.js Strong proficiency in JavaScript/TypeScript, HTML, and CSS Solid understanding of modern front-end architecture and development patterns Experience working with RESTful APIs Familiarity with front-end testing frameworks and build tools is an advantage Experience in finances/banking - nice to have

🏢 Summary: Senior Full Stack Developer role focused on designing and delivering new features for a regulatory compliance platform using a modern JavaScript stack. The position involves end-to-end development, architectural design on AWS cloud, and technical leadership within an Agile environment. You will shape the technical direction of the product while building scalable, production-ready solutions. 🗂️ Requirements: 5+ years professional software development experience, High proficiency in React, Experience with Next.js, Strong Node.js skills, Advanced GraphQL and SQL knowledge, Experience with AWS cloud infrastructure, Experience with Git and CICD pipelines, Degree in Computer Science or equivalent 📃 Skills: React, Next.js, Node.js, TypeScript, GraphQL, SQL, AWS, Terraform, Serverless, Git, CICD, DevOps, Jira 🏢 Description: About Us We are a Gliwice-based IT company supporting a British startup that helps global e-commerce brands (food, supplements, cosmetics) navigate complex regulatory compliance through an intelligent, structured platform. The Role As a Senior Full Stack Developer, you will join the product engineering team to drive the platform from concept to delivery. You will work in a modern, supportive environment, implementing new features and shaping the technical direction of the product alongside a team of highly skilled engineers. Key Responsibilities End-to-End Delivery: Design and implement new features using our modern stack (React, Next.js, Node.js, GraphQL). Architecture & Design: Apply architectural principles to build scalable solutions on AWS cloud infrastructure. Leadership: Lead code reviews, mentor junior/mid-level colleagues, and influence strategic technical decisions. Collaboration: Work closely with stakeholders and cross-functional teams in an Agile environment (DevOps/Jira). Requirements Experience: 5+ years of professional software development experience. Frontend: High proficiency in React; experience with Next.js is highly advantageous. Backend & Data: Strong skills in Node.js and advanced database programming (GraphQL/SQL). DevOps: Deep understanding of Git, CI/CD pipelines, and cloud platforms (preferably AWS). Education: Degree in Computer Science or equivalent reputable coding bootcamp. Mindset: Proactive leader with excellent communication skills and a "builder" mentality. Tech Stack: React, Next.js, Node.js, TypeScript, GraphQL, AWS (Serverless/Terraform).

🏢 Summary: A fully remote Full Stack Engineer role in a late-stage product company building a new engineering team in Poland. The position focuses on developing scalable, production-grade applications using TypeScript, React, and Node.js across the stack. Engineers collaborate cross-functionally to deliver end-to-end features with strong emphasis on quality, performance, and reliability. 🗂️ Requirements: Strong proficiency in TypeScript, Experience with React, Experience with Node.js or server-side TypeScript, Understanding of testing practices, Experience with CI/CD, Experience with version control, Ability to work in a collaborative, fast-paced environment 📃 Skills: TypeScript, React, Node.js, CI/CD, Git, APIs, Microservices, AWS, GCP, Azure, Testing 🏢 Description: A late-stage (Series D), well-funded product company is building a brand-new, fully-remote engineering team in Poland. We're looking for talented Full Stack Engineers who can build high-quality, scalable applications using TypeScript , React , and modern backend frameworks. You'll work closely with product, design, and other engineers to deliver features end-to-end. While financial markets experience is a plus, it is not required - strong engineering fundamentals matter more. We are open to candidates who specialize in only front-end or only back-end development, as well as true full-stack engineers. What You'll Do Design, build, and maintain production-grade applications using TypeScript across the stack. Develop intuitive, performant user interfaces using React and modern front-end tooling. Build and maintain backend services, APIs, and integrations (Node.js / TypeScript). Collaborate with product managers and designers to translate requirements into technical solutions. Write clean, testable, maintainable code with strong attention to performance and reliability. Participate in code reviews, architecture discussions, and continuous improvement initiatives. Troubleshoot issues across the stack and contribute to a culture of engineering excellence. Required Skills Strong proficiency in TypeScript . Experience with React for front-end development. Experience with Node.js , server-side TypeScript, or similar backend frameworks. Solid understanding of modern software engineering practices: testing, CI/CD, version control, code reviews. Ability to work in a fast-paced, collaborative environment. Nice to Have Experience working in financial markets , fintech, or trading systems. Familiarity with cloud platforms (AWS, GCP, Azure). Experience with microservices, event-driven architectures, or distributed systems. Exposure to data visualization libraries or real-time data applications. Experience with performance optimization on either the front-end or back-end.

🏢 Summary: Senior Fullstack Engineer role in a global investment firm focused on building and modernizing high-performance financial platforms. The position involves end-to-end development across backend and frontend, optimizing financial data systems, and contributing to cloud-based, distributed architectures. The role combines enterprise engineering with modern cloud and streaming technologies in a global, agile environment. 🗂️ Requirements: 7+ years of professional full-stack development experience, Hands-on experience with C# and .NET, Hands-on experience with Node.js, Hands-on experience with React, Strong knowledge of SQL Server and T-SQL, Experience designing scalable server-side applications, Experience optimizing high-throughput databases, Ability to participate in architecture and design reviews, Professional English proficiency 📃 Skills: C#, .NET, Node.js, ReactJS, AngularJS, SQL, T-SQL, SQLServer, Cloud, Containers, DataStreaming, AI, ML 🏢 Description: About the Role & Project We are recruiting for a leading global alternative investment firm (Hedge Fund) that is modernizing capital markets. We are not looking for a traditional, single-stack developer. We need a Senior Fullstack Engineer who comfortably bridges the gap between robust enterprise systems and cutting-edge cloud/AI solutions. You will join an agile tech team building high-performance platforms where your code directly impacts complex, global financial systems. Tech Stack Backend: C# / .NET, Node.js Frontend: ReactJS (with occasional legacy AngularJS maintenance) Data: SQL Server, T-SQL Architecture: Cloud, Containers, Data Streaming Key Responsibilities End-to-End Dev: Design and scale server-side apps (Node.js/.NET) and build responsive UIs (React). Data & Perf: Optimize high-throughput SQL Server stored procedures for financial data. Modernization: Leverage streaming and cloud technologies to build resilient, distributed platforms. Architecture: Take an active role in tech design reviews, architecture discussions, and mentoring. Requirements 7+ years of professional full-stack development experience. Hands-on mastery of C#/.NET, Node.js, React, and T-SQL. Engineering standards: Strong analytical skills, clean code mindset, and solid application design focus. Communication: Excellent English skills to collaborate smoothly with international teams. Bonus Points: Experience or interest in integrating AI/ML models into enterprise apps. Prior background in FinTech, banking, or trading environments . What We Offer Financial & Future: Private pension scheme, life & travel insurance, educational assistance reimbursement. Health & Wellness: Premium medical & dental package (with vision allowance) + MultiSport card. Culture & Perks: Pre-funded lunch card, Employee Assistance Program, volunteer opportunities, and active DEI affinity groups. If interested, please click apply! :)

🏢 Summary: Senior Full Stack Engineer role focused on building and optimizing React/TypeScript frontends and ASP.NET Core backend services supporting treasury workflows. The position involves designing scalable REST APIs, improving performance across the stack, and working with large datasets in production systems. Hybrid work model in Warsaw with strong emphasis on engineering best practices and reliability. 🗂️ Requirements: 5+ years of experience building production systems, Strong experience with C# and .NET ecosystem, Strong experience with ASP.NET Core, Strong experience with React, Strong experience with TypeScript, Experience designing and building REST APIs, Experience handling large datasets efficiently, Hands-on experience with ag-Grid, Highcharts or similar libraries, Understanding of authentication and authorization mechanisms, Experience with relational databases, Experience with performance optimization 📃 Skills: C#, .NET, ASP.NETCore, React, TypeScript, REST, ag-Grid, Highcharts, SQL, CI/CD, Authentication, Authorization, Serialization 🏢 Description: Senior Full Stack Engineer (.NET / React) Warsaw, hybrid, 3 days per week from the office. Responsibilities Build and enhance frontend applications and backend services supporting treasury workflows. Develop React/TypeScript single‑page applications and reusable UI components. Design and implement ASP.NET Core REST APIs with scalable pagination and filtering models. Optimize performance across the stack, including APIs, serialization, rendering, and large data grids. Collaborate with business stakeholders, quant teams, and product managers to deliver user‑focused solutions. Drive engineering best practices including code reviews, testing, CI/CD, and production support. Investigate production issues and improve observability and platform reliability. Mentor engineers and contribute to technical growth within the Warsaw team. Requirements 5+ years of software engineering experience building production systems. Strong experience with C#/.NET ecosystem and ASP.NET Core . Strong frontend experience with React and TypeScript. Experience building REST APIs and handling large datasets efficiently. Hands‑on experience with ag‑Grid, Highcharts, or similar UI/data visualization libraries. Strong understanding of authentication, authorization, and serialization mechanisms. Experience working with relational databases and performance optimization. Strong communication skills and ability to work directly with business stakeholders. Nice to Have Experience in treasury, trading, or financial systems. Strong product mindset and UX awareness.