Senior .NET Developer

Xebia is a global AI-first, digital transformation, and engineering partner. With over 25 years of experience and a team of 5,000 professionals across 16 countries, we help organizations design and build scalable products, platforms, and data-driven solutions.

About project:

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 client is a well-established global organization supporting complex business operations through modern digital solutions.

The project focuses on migrating and modernizing a business-critical enterprise platform, with the first phase establishing a reusable technical foundation and migrating an initial set of business modules. A key priority is maintaining existing functionality and complex business rules while introducing targeted improvements in usability, automation, performance, observability, and security.

You will work in an international Scrum team, collaborating closely with engineers, business stakeholders, testers, and domain experts. The project offers an opportunity to work on modern application development while tackling the challenges of enterprise migration, complex integrations, data dependencies, and business-critical systems.

You will be:

• 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.

Your profile:

• 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.

Nice to have:

• 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.