Senior .NET / C# software engineer with strong hands-on experience in backend development, APIs, SQL databases, integrations, cloud services, and AI-assisted automation. I help companies build, improve, and maintain reliable business software — from small fixes and integrations to larger backend systems, document workflows, and data-processing tools. I have worked in banking, healthcare, insurance, and enterprise environments, but I am also comfortable with focused freelance tasks where practical delivery matters more than big titles. My core stack includes C#, .NET, ASP.NET Core, SQL Server, REST APIs, Azure, Docker, Angular, Python, and AI/LLM-based tools. I can support new development, refactoring, bug fixing, data migration, automation, and technical problem solving. I am available for freelance and contract work, including short-term assignments, MVP support, backend/API development, system integration, and AI-enhanced software solutions.

Tomasz Mossakowski

Senior .NET / C# software engineer with strong hands-on experience in backend development, APIs, SQL databases, integrations, cloud services, and AI-assisted automation. I help companies build, improve, and maintain reliable business software — from small fixes and integrations to larger backend systems, document workflows, and data-processing tools. I have worked in banking, healthcare, insurance, and enterprise environments, but I am also comfortable with focused freelance tasks where practical delivery matters more than big titles. My core stack includes C#, .NET, ASP.NET Core, SQL Server, REST APIs, Azure, Docker, Angular, Python, and AI/LLM-based tools. I can support new development, refactoring, bug fixing, data migration, automation, and technical problem solving. I am available for freelance and contract work, including short-term assignments, MVP support, backend/API development, system integration, and AI-enhanced software solutions.

Available to hire

Senior .NET / C# software engineer with strong hands-on experience in backend development, APIs, SQL databases, integrations, cloud services, and AI-assisted automation.

I help companies build, improve, and maintain reliable business software — from small fixes and integrations to larger backend systems, document workflows, and data-processing tools. I have worked in banking, healthcare, insurance, and enterprise environments, but I am also comfortable with focused freelance tasks where practical delivery matters more than big titles.

My core stack includes C#, .NET, ASP.NET Core, SQL Server, REST APIs, Azure, Docker, Angular, Python, and AI/LLM-based tools. I can support new development, refactoring, bug fixing, data migration, automation, and technical problem solving.

I am available for freelance and contract work, including short-term assignments, MVP support, backend/API development, system integration, and AI-enhanced software solutions.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
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Work Experience

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Education

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Qualifications

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Industry Experience

Financial Services, Healthcare

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
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