🚀 Senior Fullstack Engineer (Java / Kotlin + React)

About the Project
We are seeking an experienced Senior Fullstack Engineer on behalf of our client—a European leader in building automation, energy management, and BMS/EMS/IoT solutions.
The project focuses on building and evolving a modern, scalable, next-generation cloud-native platform (Cloud-native / IoT), bringing together a high-performance microservices backend and modern user-facing applications.

Work Mode: 100% Remote

Start Date: ASAPDuration: long-term

Job responsibilities:
• Building and scaling complete solutions from React.js frontends to robust JVM-based microservices on the backend.
• Participating in technical discussions, designing REST APIs, and contributing to overall platform modernisations and cloud architecture.
• Collaborating directly with Product Owners to understand business goals, challenge assumptions constructively, and suggest improvements.
• Writing clean code, implementing automated testing, conducting code reviews, and maintaining comprehensive technical documentation.
• Regularly leveraging AI tools (e.g., GitHub Copilot) in daily workflows to boost development speed, generate documentation, and improve productivity.

Expectations:
• 5+ years of commercial Full-stack experience with a strong Product Mindset and proven ownership of delivered features.
• Strong knowledge of Java and/or Kotlin (JVM ecosystem, Spring Boot), microservices architecture, and REST API design.
• Hands-on experience with React.js and the modern JavaScript/TypeScript ecosystem.
• Solid understanding of Cloud-native architectures, containerization (Docker), and practical knowledge of Kubernetes (K8s).
• Daily active use of AI-assisted tools (Copilot, ChatGPT, etc.) paired with critical code review skills.
• Fluent English (C1 level) for seamless collaboration in an international environment.
• (Nice to Have): Experience with SaaS platforms or event-driven architecture, prior domain exposure to IoT, BMS, HVAC, SCADA, or industrial automation, and working knowledge of German.

We offer

• Ongoing support from a dedicated agent, taking care of your project continuity, client contact, necessary formalities, work comfort and development
•

Consultant Development Program – advice on growth planning based on the latest trends and market needs in IT, including consultations with agents and growth mentors
• Access to 7N Learning & Development – a development and educational platform with webinars, a library of articles and industry reports, and regular invitations to one-time and recurring development events – technical, business, and lifestyle
• Spectacular integration events, both for you (e.g., annual Kick-Off trip, Christmas parties, or Summer Olympics sports events) and for your loved ones (e.g., family picnics, movie premieres)
• Professional development not only during the project – you can get involved in knowledge transfer to others within the 7N Services offering directed at 7N clients
• Relationships and access to the knowledge of the most experienced IT experts in the market – the average professional tenure of our consultants in Poland is over 10 years
• A complete benefits package, including funding for medical care, life insurance, sports cards for you and your loved ones, as well as discounts in stores in Poland and abroad

About 7N
Constantly searching for projects, difficult rate negotiations, lack of development support – sounds familiar? At 7N, you gain not only stability of contracts but also the personal involvement of a dedicated agent who ensures your professional comfort and continuous access to development initiatives.
Our mission is to provide stable and rewarding collaborations that drive your success as an IT expert and the success of our clients. We build long-lasting relationships based on Scandinavian values and 30 years of experience creating IT solutions for over 200 organizations.