Senior Full-Stack Developer (React/Next.js + .NET/C#)

We are excited to announce the development of our new Software Development Hub in Warsaw - an important step in our journey of global growth.  

This initiative marks an important step forward in bringing together top technical talent, optimizing our processes, and shaping the future direction of our organization.  

Job Overview: 
We are searching for a highly skilled and experienced Senior Full-Stack Developer to join our team. This role is perfect for someone equally comfortable designing scalable frontend solutions with React and Next.js, as well as building and maintaining backend services using C# and .NET.  

As a senior member of the team, you will contribute to the full development lifecycle, from planning and decision-making to hands-on technical delivery. You’ll play a critical role in ensuring technical excellence and improving the application architecture while understanding the trade-offs of various development choices. Strong collaboration and communication skills are paramount, as you’ll work closely with cross-functional teams to deliver impactful, scalable, and maintainable applications.  

Responsibilities:  

• Build and maintain full-stack applications using React, Next.js, TypeScript, C#, and .NET.  
• Design and implement frontend components and features with a focus on maintainability, performance, and scalability.  
• Create and optimize scalable backend services, ensuring high availability and smooth integration with the frontend.  
• Drive architectural decisions that strengthen application design while balancing trade-offs between speed, quality, and scalability.  
• Contribute to API design and implementation, following modern standards like REST and GraphQL.  
• Ensure code quality through unit testing, automated testing, and thoughtful code reviews.  
• Support team growth by sharing knowledge, fostering best practices, and contributing to a culture of continuous learning. 

Required Skills & Qualifications:  

• 5+ years of professional experience in full-stack development, with strong expertise in both frontend and backend.  
• Proficiency in React, Next.js, and TypeScript for modern frontend development.  
• Solid background in backend development using C# and .NET, with the ability to design scalable APIs and services.  
• Strong understanding of software engineering principles, design patterns, and best practices.  
• Experience with unit testing, writing maintainable code, and improving software quality through automated tests.  
• Strong debugging, troubleshooting, and problem-solving abilities.  
• Strong communication and collaboration skills to work effectively within a team environment.  
• Ability to evaluate and articulate the pros and cons of various technical approaches to inform decision-making. 

Nice-to-have Skills & Qualifications:   

• Experience with authentication and authorization setups.  
• Experience with event streaming and event based systems.  
• Exposure to DevOps practices, CI/CD pipelines, and containerization tools like Docker and Kubernetes.  
• Knowledge of Identity and Access Management (IAM) solutions like Keycloak or Microsoft Entra ID. 

What We Offer:

• Constructive cooperation based on trust and respect for the employee 
• Bonus system 
• Employee Pension Scheme financed entirely by the employer (PPE) 
• Attractive well-being package (platform MyBenefit, life insurance, lunch card, gift cards) 
• Private medical care with telemedicine and rehabilitation 
• Employee Foundation support 
• Internal development programs  
• Remote work (2 times per week) and workation  
• Flexible working hours 
• Additional 2 days of holiday for volunteering 

Ready to apply?  

Learn more about the VELUX Group online at www.velux.com where you can read more about working at our company and what to expect of our recruitment process.  

We look forward to receiving your application and CV as soon as possible. We are conducting interviews on an ongoing basis until we have the right match.  

All inquiries will be treated confidentially.  

About VELUX  

In the VELUX Group, we offer you a world of opportunities and the chance to create a bright future. From the forefro