C#.Net Windows Developer

Senior Software Developer

Position Purpose

We are seeking three Senior Software Developers to modernize a business-critical WPF application with significant technical debt. The role will focus on progressively refactoring tightly coupled legacy code into a modular, testable architecture using the MVVM pattern and a dedicated service layer, while enabling ongoing business feature development to continue.

Key Responsibilities

• Refactor legacy WPF modules and screens into a clean MVVM architecture with clear separation of concerns.
• Design and implement service-layer abstractions that decouple ViewModels from business logic and infrastructure dependencies.
• Apply dependency injection and inversion-of-control practices using suitable .NET containers, including Microsoft.Extensions.DependencyInjection where appropriate.
• Create and maintain automated unit tests using frameworks such as xUnit or NUnit, with mocking through Moq or equivalent tools.
• Preserve existing business behavior during incremental migration and support coexistence between legacy and modernized modules.
• Follow established code guidance, project folder structures, UML designs, and internal architectural governance.
• Use Visual Studio Code Metrics, code analysis capabilities, and SonarQube quality gates to track maintainability, complexity, standards compliance, and technical-debt reduction.
• Participate in code reviews, technical discussions, and delivery planning with internal technical leaders.
• Deliver production-quality code with minimal supervision and contribute immediately to the refactoring program.

Required Qualifications and Experience

• Strong professional experience developing desktop applications using C#, .NET, WPF, and XAML.
• Advanced hands-on expertise in MVVM, including data binding, commands, resources, UI lifecycle management, and ViewModel design.
• Practical experience with MVVM frameworks such as CommunityToolkit.Mvvm, Prism, or comparable frameworks.
• Deep understanding of dependency injection, interface-driven design, service abstractions, and IoC containers.
• Demonstrated experience refactoring complex, tightly coupled legacy applications into modular components.
• Strong unit-testing skills using xUnit or NUnit and mocking frameworks such as Moq.
• Hands-on experience with static code analysis and technical-debt management using SonarQube and Visual Studio tooling.
• Ability to interpret and implement architectural documentation, code standards, folder conventions, and UML diagrams.
• Proven ability to work independently in a senior engineering role and contribute with minimal technology ramp-up.

Preferred Attributes

• Experience modernizing large-scale or business-critical WPF applications through incremental migration.
• Familiarity with parallel refactoring strategies that allow feature development and modernization to proceed concurrently.
• Strong analytical, troubleshooting, and communication skills in a cross-functional engineering environment.
• Quality-first mindset with disciplined use of automated tests, code reviews, and measurable engineering metrics.