Senior .NET developer

We're seeking a seasoned .NET Software Engineer to join a dynamic Agile team within a financial technology division. You'll play a key role in enhancing and expanding a cutting-edge cloud-native payment platform. This position offers the opportunity to engage in end-to-end development processes using modern tools and practices. Expect hands-on work with technologies like .NET Core, AWS, C#, RESTful APIs, and microservices.

This is a senior-level engineering role focused on designing scalable, high-quality software, contributing to system architecture, and promoting efficient development practices such as CI/CD, Git Flow, and Infrastructure as Code. You'll also be expected to support team growth and help improve operational and development performance.English Proficiency: B2+ level required.

Oferujemy

100% remote within Poland (though preference is given to candidates located in or near Kraków)Rate (B2B Contract): 110-130zł/h netto

Obowiązki

Wymagania

• 5+ years of experience as a professional software developer in a modern development setting

• Proficiency in C# and recent .NET versions (LTS) for scalable solution development

• Solid expertise with Web API and Minimal APIs to build well-structured, efficient endpoints

• Familiarity with MassTransit and messaging brokers like RabbitMQ or Azure Service Bus

• Use of MediatR for in-process messaging patterns and separation of concerns (CQRS principles)

• Experience applying Domain-Driven Design (DDD) to align code structure with business logic

• Understanding of Event-Driven Architecture for flexible and scalable service interactions

• Knowledge of asynchronous programming, including multithreading and parallel execution

• Comfortable mentoring junior colleagues and fostering team capability

• Skilled at engaging stakeholders to ensure technical goals align with business needs

• Experience guiding architectural decisions and code review practices

• Effective collaboration with cross-functional teams to unify development efforts

• Strong initiative in enhancing application performance, resilience, and overall DX

• Adept at reviewing code for maintainability and sharing best practices

• Solid knowledge of both relational (SQL) and non-relational (NoSQL) databases

• Background in code refactoring and legacy system improvement

• Thorough grasp of design principles and software architecture patterns

• Familiar with CI/CD workflows and deployment automation

• Understanding of secure coding, including OWASP standards

  Nice to Have:

  • Familiarity with PCI DSS compliance

  • Previous experience in payment processing or fintech projects

  • Hands-on with Command Query Responsibility Segregation (CQR