Ion Guzun

Senior .NET / Blazor Fullstack Developer · RTI Solutions

A large retail payment provider scaling its platform for brands like Metro, L'Oréal and Adidas.

• Built a greenfield application with RESTful services served through an API Gateway in .NET 10 and C#.
• Integrated a low-level POS fiscal payment system supporting 1,000 concurrent devices.
• Rolled out company-wide branding across the CRM using Blazor and Syncfusion.

Stack: C# 14 · .NET 10 · EF Core · DDD · MediatR · ESC/POS · LibUsbDotNet · Blazor · Syncfusion · Aspire · PostgreSQL · Azure Key Vault · NUnit · MSTest · Moq

.NET / Blazor Fullstack Developer · DENS Solutions

A pharma & battery research company in the Netherlands streamlining its scientific data workflows.

• Consolidated many fragmented tools into a single modern app on a modular-monolith architecture (.NET 8 + Blazor).
• Built image-processing pipelines for electron-microscope data — nano-meter accuracy, DM4 parsing, classification and OpenCV-based normalization.
• Developed export modules for MP4 video and multiple image formats used in scientific publications.
• Hardened the system: migrated .NET 6 → 8, added unit tests (NUnit, Moq) and Azure AD security.

Stack: .NET 8 · C# 12 · Python · MVVM · gRPC / Protobuf · OAuth · Blazor · .NET MAUI · TypeScript · SciChart · Fabric.js · HDF5 · OpenCV · NumPy · pandas · FFmpeg · GitHub Actions · Azure AD

.NET / Blazor Fullstack Developer · Alvys

A transportation & logistics CRM used by dispatchers and drivers across the operation.

• Implemented the accidents, claims and maintenance modules in .NET Core, improving manager oversight.
• Led the migration from ASP.NET to ASP.NET Core and added NUnit coverage for core modules.
• Collaborated across a cross-functional team of 30 developers from different departments.

Stack: C# 10 · ASP.NET Core · ASP.NET Web API · MVC · LINQ · REST · Blazor · Cosmos DB · NUnit · Moq · Mailchimp · Azure DevOps