B2B

.NET

📍 Kraków, Poland (Hybrid)

We are looking for a Senior Backend Software Engineer to help build and scale a modern cloud-native SaaS platform used by customers globally.

In this role, you will work on high-availability backend systems, distributed services, and scalable APIs powering customer-facing applications. You’ll collaborate closely with international engineering teams, product managers, and frontend developers to deliver reliable, secure, and high-performing solutions in a fast-paced agile environment.

This is an opportunity to join a modern product-focused engineering environment where backend architecture, scalability, and engineering quality are highly valued.

Responsibilities

Design, develop, and maintain scalable backend services using C# and .NET 6+
Build and optimise RESTful APIs for modern web applications
Contribute to the evolution of a microservices-based architecture focused on scalability and resilience
Develop cloud-native solutions leveraging AWS services
Ensure systems are secure, highly available, and performant
Collaborate with frontend engineers to support seamless API integrations
Partner with product and design teams to translate business requirements into technical solutions
Participate in architecture discussions, technical planning, and code reviews
Write clean, maintainable, and well-tested code following engineering best practices
Implement and improve automated testing strategies including unit and integration testing
Identify and reduce technical debt while improving long-term system sustainability
Monitor application performance and contribute to reliability and observability improvements
Support CI/CD and deployment processes within an agile development environment
Stay up to date with emerging technologies and contribute to continuous improvement initiatives.

Required Qualifications

5+ years of experience in backend software engineering within product, SaaS, or web environments
Strong proficiency in C#, .NET, and ASP.NET Core
Experience designing and building scalable web applications and REST APIs
Solid understanding of distributed systems and cloud-native architecture principles
Hands-on experience with AWS or similar cloud platforms
Experience working with microservices and event-driven architectures
Strong knowledge of relational databases such as SQL Server
Experience with ORM frameworks such as Entity Framework
Understanding of software design patterns and clean architecture principles
Experience working in agile development teams
Strong communication and collaboration skills.

Nice to Have

Experience with AWS services such as Lambda, API Gateway, DynamoDB, or Elasticsearch
Familiarity with Infrastructure as Code tools such as Terraform
Experience with CI/CD pipelines and automation tools
Knowledge of Docker and Kubernetes
Exposure to serverless architectures
Experience supporting backend systems for React-based frontend applications
Familiarity with observability and monitoring tools
Experience working in distributed international teams.

What We Offer

Opportunity to work on modern cloud-native products and large-scale distributed systems
Collaborative international engineering environment
Flexible hybrid working model in Kraków
Career growth opportunities and continuous learning support
Exposure to modern technologies, architecture, and engineering practices
Competitive compensation and benefits package
Supportive team culture focused on innovation and technical excellence.