Senior Lead Developer - .NET / Microservices

Company Description Our mission as a company providing IT services is to provide our clients all over the world with the best solutions. We manage to do this by analyzing the needs of our clients and matching them to the skills and aspirations of our employees. Therefore, one of our main motivations is to provide each Employee and Consultant with a satisfying experience. Joining us means being part of a community with diverse personalities. Start your adventure with act digital Polska! Job Description Modernisation of an existing .NET solution by migrating from a monolithic architecture to a scalable microservices-based architecture running on Red Hat OpenShift, driven by the implementation of new regulations. The backend communicates with the Angular frontend via REST APIs, with MS SQL Server used for data storage. Responsibilities Design and implement microservices solutions and decompose the existing monolithic application. Develop scalable backend services using C#/.NET, REST/WebSockets and collaborate with frontend teams. Work with event-driven architecture, Kafka and integrations, while optimising application performance and scalability. Conduct code reviews, prepare technical documentation and support analysts with business requirements analysis. Requirements 5+ years of experience as Senior Developer (C#, .NET). 2+ years of experience as a Lead. Experience with microservices (SAGA/ Service Discovery/ Circuit Breaker/ API Gateway (KONGpreferred)), architectural patterns, DDD. REST APIs / WebSockets. Docker, Kubernetes, Red Hat OpenShift. Experience with a cloud (Azure or AWS), Azure DevOps / CI/CD. Experience with Kafka, event-driven architecture, asynchronous messaging. Good knowledge with SQL/NoSQL and distributed data management. Automated unit/integration testing. Monitoring, logging and distributed tracing experience (Prometheus / Grafana / ELK / Jaege) Authorization experience (JWT/OAuth2). Fluent English. Nice to have Service Mesh. Experience with AI, prompting and AI-assisted development. Angular. Additional Information Type of contract: B2B Rate: up to 200 PLN/H net + VAT We offer Access to local and international projects - Clients from France, Germany, Portugal, UK, and Benelux. Professional development support - trainings, technical certificates, conference participation, foreign language classes, and soft skills trainings are subsidized for up to 2 000 PLN. Bonus for recommending Candidates starting from 6 000 up to 10000 PLN. Fully paid Medicover healthcare card. Psychological support program WellBee. Multisport card. Regular integration events and gifts. Long-term cooperation. Relocation Program. If You applied for this position the Controller of your personal will be ACT DIGITAL POLSKA Sp. z o.o., with its registered office at Przyokopowa 31, 01-208 Warsaw. The personal data provided by you will be processed for the purpose of the recruitment process and for future recruitment processes. You have the right to access the content of your data, request their rectification, erasure, restriction of processing, the right to data portability, the right to object to the processing of your data and the right to lodge a complaint to the President of the Personal Data Protection Office.