[Hiring] Senior .NET Developer @Poland and Middle-Eastern Europe

Role Description

We are looking for a .NET Developer to join a project delivered for our international client operating in the rail transportation and asset-leasing industry . The project focuses on migrating and modernizing a business-critical enterprise platform.

• Developing and maintaining backend applications using C# and .NET .
• Building and integrating REST APIs and ASP.NET Core WebAPI services.
• Migrating existing business functionality while maintaining functional parity and business rules.
• Contributing to a reusable application platform with shared components and common development patterns.
• Working with PostgreSQL and application data models, including data migration and system dependencies.
• Integrating the platform with enterprise systems and other business applications.
• Analyzing existing processes and translating complex business requirements into reliable technical solutions.
• Contributing to automated testing using xUnit and applying TDD principles where appropriate.
• Troubleshooting applications and contributing to improvements in performance, observability, security, and maintainability.
• Participating in code reviews, technical discussions, refinement, planning, and other Scrum activities.
• Collaborating closely with business stakeholders and domain experts to understand existing functionality and business rules.
• Supporting incremental releases, user acceptance testing, and post-release stabilization.
• Using AI-powered development assistants such as Claude Code, GitHub Copilot, or Cursor to improve productivity and software delivery.
• Depending on seniority, taking ownership of technical topics, proposing improvements, and supporting less experienced team members.

Qualifications

• Strong knowledge of C# and .NET .
• Practical experience with ASP.NET Core and WebAPI .
• Experience designing and developing REST APIs and backend services.
• Practical experience with relational databases, preferably PostgreSQL .
• Experience with Entity Framework / Entity Framework Core .
• Solid understanding of object-oriented programming, clean code, and software design principles.
• Experience with automated testing and TDD , preferably using xUnit .
• Experience with Git and standard software development workflows.
• Ability to understand existing systems, business rules, dependencies, and technical constraints.
• Good problem-solving and analytical skills.
• Ability to collaborate effectively with engineers, business stakeholders, and domain experts.
• Practical experience using AI-powered development assistants such as Claude Code, GitHub Copilot, or Cursor.
• Work from the European Union region and a valid work permit are required.

Requirements

• Experience working on enterprise application migration or modernization projects .
• Experience with AWS and cloud-based application environments.
• Experience with Docker .
• Experience with Terraform or infrastructure-as-code.
• Experience with Azure DevOps .
• Familiarity with frontend technologies such as React and TypeScript .
• Experience with automated frontend or end-to-end testing using Vitest or Playwright .
• Experience applying GenAI in a more structured way within the SDLC, including defined workflows, prompt patterns, or tool integrations embedded into daily work.
• Interest in and familiarity with emerging AI-driven practices (e.g. agent-based workflows, automation patterns, AI-augmented development), with a willingness to explore and experiment beyond standard approaches.

Recruitment Process

• CV review
• HR call
• Interview
• Client Interview
• Decision