Senior .NET Engineer

DOU Polska; Kraków; Hybrid; PLN 180,000 - 300,000; Full time

Benefits offered by this job

Cloud-native projects

International team

Hybrid in Kraków

Career growth

Modern technologies exposure

Competitive compensation

Supportive team culture

Job summary

DOU Polska in Kraków (Hybrid) is 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 design and maintain scalable backend services with C# and AWS, collaborate with international teams, and deliver reliable, secure APIs in a fast-paced agile environment.

You will work on microservices, REST APIs, and cloud-native architectures, participate in architecture discussions, enforce quality through

Qualifications

• 5+ years of backend software engineering experience in SaaS or web products.
• Strong proficiency in C#, .NET, and ASP.NET Core.
• Experience designing scalable web apps and REST APIs.
• Knowledge of relational databases such as SQL Server and EF.

Responsibilities

• Design, develop, and maintain scalable backend services in C# and .NET 6+.
• Build and optimise RESTful APIs for modern web applications.
• Contribute to 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 for seamless API integrations.
• Partner with product and design teams to translate requirements into solutions.
• Participate in architecture discussions, planning, and code reviews.
• Write clean, well-tested code following engineering best practices.
• Implement and improve automated testing strategies (unit/integration).
• Identify and reduce technical debt while improving long-term sustainability.
• Monitor performance and contribute to observability improvements.
• Support CI/CD and deployment processes within an agile environment.
• Stay up to date with emerging technologies and drive continuous improvement.

Skills

C#

ASP.NET Core

REST APIs

Distributed systems

AWS

Microservices

SQL Server

Entity Framework

Clean Architecture

Agile

Tools

Docker

Kubernetes

Terraform

CI/CD Tools

Job description

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 will 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 principlesExperience 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.