Danijel B.

I help companies keep their .NET systems fast, stable and up to date: new ASP.NET Core APIs, fixes in existing code, and migrations from .NET Framework to .NET 8. 10+ years, 2,000+ Upwork hours, 100% Job Success. Available 1pm–9pm US Eastern. What I've delivered: ✅ Migrated 20 legacy .NET Framework apps to .NET Core with zero downtime ✅ REST APIs handling 1,000+ requests/day, saving one client 20 hours/week of manual work ✅ Long-term engagements up to 1,100 hours with repeat clients ✅ 10+ years building internal .NET and ERP systems for an enterprise retail group (Dynamics NAV integration, SQL Server) A good fit if you: → have an existing .NET app that needs new features, bug fixes or a steady senior developer → want to move from .NET Framework to .NET 8 without breaking production → need a clean, documented ASP.NET Core API What I work with: → Backend: C#, ASP.NET Core, .NET 6/7/8/9/10, Web API, Entity Framework, Dapper → Architecture: Microservices, Clean Architecture, Domain-Driven Design, CQRS → Cloud: Azure (App Service, Functions, DevOps, OpenAI Service), CI/CD pipelines → Data: SQL Server, Python, PySpark, Databricks, ETL → Frontend (when needed): Angular, JavaScript, React How I work: a clear estimate before I start, short updates during the work, and clean code in your repo from day one. Send me a few lines about your project and I'll reply with a first step and an estimate.