(Senior) Software Engineer .NET - Backend

Senior Software Engineer – Backend (.NET) Location: Kraków, Poland Working model: Hybrid – 4 days (in-office) Level: Senior Department: Engineering Love solving complex engineering challenges and building software that scales? Let’s build something great together - Join an international engineering team creating enterprise SaaS products used by customers around the world. We’re looking for a Senior Backend Engineer who enjoys tackling technical challenges, sharing ideas and turning thoughtful design into reliable, high-performing software. Working with C#, .NET, ASP.NET Core, microservices and AWS, you’ll help shape secure, resilient backend platforms—and have a voice in the technical decisions behind them. What You’ll Be Doing - - Build and evolve high-performance backend services using C# and .NET. - Design secure, reliable RESTful APIs that power our products. - Develop microservices and cloud-native applications on AWS. - Solve challenges in performance, scalability, reliability and security. - Work closely with Product Managers, Architects and Frontend Engineers to bring ideas to life. - Help shape architecture and technical design through open discussion and practical recommendations. - Share knowledge through thoughtful code reviews and champion strong engineering practices. - Build automated unit, integration and end-to-end tests that support confident releases. - Improve CI/CD pipelines and deployment automation. - Investigate production issues and turn what you learn into lasting improvements. - Tackle technical debt and keep our systems maintainable as they grow. What You’ll Bring - - 5+ years of professional backend software development experience. - Experience building enterprise web applications or cloud-based SaaS platforms. - A strong understanding of the full software development lifecycle. - Strong hands-on experience with C# and .NET 6+, ASP.NET Core, ASP.NET MVC / Blazor, Entity Framework and SQL Server. - Experience designing and building RESTful APIs, microservices, distributed systems and event-driven architectures. - A solid understanding of secure API development. - Commercial experience with AWS and cloud-native development. - Strong system design skills, with an understanding of scalability, distributed computing and performance engineering. Bonus Points For - - AWS: Lambda, API Gateway, DynamoDB, RDS / SQL Server and Elasticsearch. - DevOps: Terraform, GitHub Actions, TeamCity, Docker, Kubernetes and CI/CD. - Observability: Monitoring, logging, metrics and distributed tracing. - Architecture: Serverless solutions, high-volume distributed systems and backend services supporting React applications. How We Work - We value engineers who ask good questions, take ownership and enjoy working through complex problems together. Clear communication, constructive feedback and a willingness to keep learning are central to how we build. You’ll join a collaborative international team where you can share your expertise, influence technical direction and work with modern cloud-native architectures and distributed systems. Ready to help shape what we build next? Apply now or get in touch - we’d love to hear from you. #Hiring #SoftwareEngineer #SeniorSoftwareEngineer #DotNet #CSharp #BackendDeveloper #AWS #Cloud #Microservices #Krakow #Poland #TechJobs #EngineeringJobs