Senior .NET / C# Software Engineer (Windows Systems) Warsaw

Job Title:
Senior Windows Software Engineer (C# / .NET)

About the Role & Product:
Adaptiq is looking for a Senior Windows Engineer to join an international product team developing a mature commercial enterprise platform. You will work on a substantial codebase, driving features from investigation through implementation to production support, while optimizing system performance and modernizing core components.

Key Responsibilities:
Develop and maintain Windows-based software primarily using C#/.NET.
Investigate complex issues, debug, and optimize software performance across a mature codebase.
Work with legacy components, including C++ code when necessary.
Take end-to-end technical ownership of feature delivery and problem resolution.
Use AI-assisted development tools (Copilot, Cursor, etc.) in your daily engineering workflow.

Required Skills:
6+ years of professional software engineering experience with strong expertise in C#/.NET.
Proven track record in developing and maintaining Windows-based desktop/system software.
Strong debugging, performance profiling, and problem-solving skills in complex codebases.
Readiness to read, debug, and modify existing C++ code.
Practical experience with modern AI coding tools.
Upper-Intermediate English level (or higher) with strong communication skills.

Nice to Have:
Experience developing endpoint agents, background services (Windows Services), or long-running software.
Hands-on C++ development experience.
Background in virtualized desktop environments (VDI).

We Offer:
100% Fully Remote work model + hardware/coworking support.
20 business days of paid vacation + national holidays.
Full legal and B2B accounting support in Poland.