Senior Full-Stack Engineer

For a client, we are looking for a Senior Full-Stack Engineer (NodeJS + React)! Salary: 24 000-27 000 net+VAT B2B 100% remote RESPONSIBILITIES Architecture, production, and reliability experience: Proven experience designing systems from scratch or significantly evolving existing architectures Experience working on production systems with real users Strong understanding of architectural trade-offs (performance, scalability, cost, and maintainability) Experience with monitoring, debugging, and performance optimization in production environments Familiarity with handling production issues and incidents Ownership and leadership: Experience owning major system components or leading technical decisions Ability to work independently with minimal supervision Experience mentoring junior or mid-level developers and collaborating within a team REQUIREMENTS At least 10 years of professional software development experience Proven experience working with SaaS-based systems Strong understanding of scalable systems and software architecture Hands-on experience with Node.js and React Excellent English proficiency and strong communication skills NICE TO HAVE Experience with cloud platforms such as AWS, GCP, or Azure Familiarity with CI/CD pipelines and modern DevOps practices Experience working in distributed or remote teams Product mindset — ability to understand business requirements and translate them into technical solution WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract and rate: 24 000-27 000 PLN/hour 100% remote work The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join Lumen Dynamics, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, life insurance, Multisport card). WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a Lumen Dynamics recruiter about your experience. Next steps: The Lumen Dynamics recruiter will explain the recruitment process for the specific position. The Lumen Dynamics recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At Lumen Dynamics, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch. DO YOU HAVE ANY QUESTIONS? Contact the recruiter responsible for this process directly. Iga Olszewska-Magnowska Senior IT Delivery Consultant iga.olszewska@Lumen Dynamics.pl