Mateusz Kowalewski, Developer in Gdańsk, Poland
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Mateusz Kowalewski

Verified Expert  in Engineering

Solutions Architect and Software Developer

Gdańsk, Poland
Toptal Member Since
January 19, 2022

Mateusz is a solutions architect with 10+ years of experience with .NET and a proven track record of delivering projects of various sizes and complexity, from €100,000 T&M initiatives to €1,000,000 fixed-price programs. He keeps solutions simple and cognitive complexity low. His main areas of activity are presales, project estimation and planning, bootstrapping projects, technical cooperation with customers, technical supervision and leadership, and organization-wide technical strategy.


Azure, Windows Presentation Foundation (WPF), Blazor, Xamarin, .NET, .NET Core...
Azure, .NET, Microsoft Azure
C#, .NET, Windows Presentation Foundation (WPF), Microsoft Silverlight, Prism...




Preferred Environment

Visual Studio, Microsoft Teams, Windows

The most amazing...

...thing I've delivered is a €1 million fixed-price program consisting of desktop and cloud applications for making measurements of distance on photos.

Work Experience

Solutions Architect

2015 - PRESENT
  • Conducted technical supervision over developers. My other responsibilities were bootstrapping projects, architecture governance, and technical leadership over agile teams.
  • Estimated the projects and made them happen. Contacted and consulted customers. Advised them toward suitable solutions.
  • Contributed to SEM, an engineering methodology that introduces delivery process standardization in the organization of 300 developers.
  • Helped with the delivery of around 50 projects from .NET or Azure. Some projects were straightforward, with a small team, time, and material model, and some of them were fixed-price programs worth over 1,000,000 euros.
Technologies: Azure, Windows Presentation Foundation (WPF), Blazor, Xamarin, .NET, .NET Core, CQRS, Domain-driven Design (DDD), Test-driven Development (TDD), Solution Architecture, Microsoft Azure

Technical Leader

2014 - 2015
  • Led a team of four. Transformed the Windows Phone mobile app with C++ back end into cross-platform Xamarin-based app with .NET and Azure back end.
  • Developed a long-term P2P loan platform, leading a team of five. Extended and refactored the .NET back end hosted on Azure.
  • Managed a team of three. Created a few C4 drivers for various fire protection and alarm systems. The drivers were part of a highly regulated ecosystem.
Technologies: Azure, .NET, Microsoft Azure

Owner, Software Developer, and Architect

2011 - 2014
  • Developed an e-learning solution for a local English language school.
  • Created a solution for planning activities in companies that hire trainers who perform courses with trainees. It includes the whole business process, from managing people up to accounting.
  • Developed Funeral System, a system for comprehensive management of funeral houses.
  • Created Asyc.Core, a framework for fast LOB application development.
  • Created NeuroLogo, a system that helps therapists in aphasia treatment.
  • Built a Windows desktop client for a Dropbox-like system.
Technologies: C#, .NET, Windows Presentation Foundation (WPF), Microsoft Silverlight, Prism, Microsoft Azure

Senior Software Engineer

2012 - 2013
  • Re-engineered a framework for OpenCL driver validation.
  • Developed the Hydra Topology Explorer. This tool is still in use and can be considered a visualization tool for early IoT.
  • Supervised interns and performed a series of technical pieces of training in the C# and .NET domains.
Technologies: C#, .NET

Software Developer

2008 - 2011
Wolters Kluwer
  • Developed the desktop versions of LEX and ABC, industry-leading legal applications.
  • Learned how to work within a big team, working together on a 25-million LOC solution.
  • Introduced algorithms that significantly improved the performance of searching visualization.
Technologies: C++, Microsoft Foundation Class (MFC) Library, Microsoft Foundation Classes (MFC), ERC-20, Standard Template Library (STL)

Software Developer

2006 - 2011
  • Created custom software mainly for the funeral industry.
  • Learned full software development lifecycle, including the requirement analysis phase.
  • Developed many applications, three of which are still on the market—obituary designer, ribbon designer, and card designer.
Technologies: .NET, Windows Forms (WinForms), Entity Framework, C++, Visual Component Library (VCL)


The Leica BLK3D is a measurement solution based on photos. Each photo captured is a complete measurement record that contains height, width, and depth measurements. Measurements can be created at any point, right away on-site using the handheld BLK3D Imager, or at any point in time after that using the BLK3D Desktop Software.


Single sign-on for all 1,000+ digital learning products for the whole company. Integrated with external credential providers (structure of all 2,000,000+ students in Denmark) and prepared for high traffic peaks.

National Criminal Register

Acted as Lead Solution Architect for v2 of the National Criminal Register. Polish Ministry of Justice sponsored this big, public, fixed-price initiative. The main purpose of it was to eliminate human involvement from the process to the greatest possible extent, and the environment of execution was highly regulated—driven by polish law.
2011 - 2013

Master's Degree in Computer Science

Gdańsk University of Technology - Gdańsk, Poland

2008 - 2011

Engineer's Degree in Computer Science

Gdańsk University of Technology - Gdańsk, Poland


TOGAF 9 Certified

The Open Group


Microsoft Azure Solutions Architect Expert



Xamarin Certified Developer



Entity Framework, Microsoft Foundation Class (MFC) Library, Standard Template Library (STL), Windows Forms (WinForms), Visual Component Library (VCL), Microsoft Foundation Classes (MFC)


Microsoft Silverlight, Prism, RabbitMQ


Azure, Xamarin


C#, C++, SQL


.NET, .NET Core, Blazor, Entity Framework Core, ASP.NET MVC, ASP.NET Core, Windows Presentation Foundation (WPF), TOGAF, Angular, MassTransit




Azure DevOps, CQRS, Model View ViewModel (MVVM), Microservices, Test-driven Development (TDD), Refactoring


Solution Architecture, Microsoft Azure, Azure Resource Manager (ARM), Infrastructure as Code (IaC), Domain-driven Design (DDD), ERC-20, Architecture, Production

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