Senior Fullstack Engineer

Join our client's team as a Senior Full-Stack Engineer! RESPONSIBILITIES Own features end-to-end — from API and data model on the backend to the UI on the frontend Build and maintain backend services in Java, and rich interfaces in React Contribute to our shared UI component library and backend architecture alike Take part in code reviews across the stack — backend, frontend, and the glue in between REQUIREMENTS Strong backend skills in Java 21 with Spring / Spring Boot and Hibernate Solid frontend experience with JavaScript, TypeScript, React, and Redux Toolkit Good grasp of relational databases, especially MariaDB Linux skills at user level or above, plus confident Git workflows You write well-tested, maintainable code on both sides of the stack Advanced technical English for design, review, and documentation\ Proven experience with cloud-native platforms such as Kubernetes Comfortable using AI tools (coding assistants, LLMs) as part of your daily workflow — and the judgment to know when to trust them and when to think for yourself NICE TO HAVE Experience building software for telecommunication systems Knowledge of protocols like IPv4/6, DNS, BGP, DHCP, SR, and ZTP Data visualization libraries — Cytoscape.js, react-chartjs-2, MapLibre, or similar Storybook, mono-repo tooling (Lerna), or Webpack experience Automation tools such as Ansible or Terraform Understanding of Linux and Kubernetes networking (routing, iptables, CNI) WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract and rate: 160-180 PLN/hour Hybrid work from Kraków (1 times a week in the office) The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join Nimbus Data Systems, 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, 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 Nimbus Data Systems recruiter about your experience. Next steps: The Nimbus Data Systems recruiter will explain the recruitment process for the specific position. The Nimbus Data Systems recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At Nimbus Data Systems, 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. Karolina Kizowska Senior IT Delivery Consultant karolina.kizowska@Nimbus Data Systems.pl +48 608 487 448