What is a .NET developer?
A .NET developer is a software engineer who builds applications on the Microsoft .NET platform — primarily in C# (the dominant .NET language), occasionally F# or VB.NET. The work spans web applications (ASP.NET Core), desktop and mobile apps (MAUI, WPF, WinUI), backend services and APIs, Windows Services, Azure-hosted workloads, and Microsoft-shop enterprise integrations (SQL Server, Entra ID, Microsoft 365). .NET 10 is the current LTS at the time of writing.
The longer answer
.NET is Microsoft\'s cross-platform application framework. It is unique in the major-framework landscape for being equally credible on Windows, Linux, macOS, iOS, Android, and the web — a single language (C#) and a single runtime (.NET) cover desktop, mobile, web, backend, and embedded. That cross-platform reach is the strongest argument for picking .NET as a stack: an engineering team can build for every surface without learning four different runtimes.
Where .NET dominates
Microsoft-shop enterprises — businesses already running Microsoft 365, Azure AD / Entra ID, SQL Server, Power BI, and Windows desktops — are the canonical .NET buyer. The integration depth between .NET and the Microsoft enterprise stack is substantially better than any other framework. ASP.NET Core for web backends, Entity Framework Core for data access, MAUI for cross-platform mobile, and Azure App Service or Azure Functions for hosting form a tight, well-integrated production posture.
What changed with .NET 10
.NET 10 (Long-Term Support, late 2025 release) extends the .NET 8 LTS line: continued runtime performance improvements, Native AOT maturity for both ASP.NET Core and MAUI, and substantial language polish in C# 13 (params collections, partial properties, lock-statement improvements). For new builds in 2026, .NET 10 is the right floor; older codebases on .NET 6 or .NET Framework 4.8 should plan a modernization path.
What a senior .NET developer brings beyond C# fluency
Three signals: dependency-injection discipline (using the built-in DI container correctly, not just grafting Unity on top), async/await fluency (knowing when to use ConfigureAwait, when to use ValueTask, and how to debug deadlocks), and production-deployment posture (Azure App Service or container orchestration, Application Insights / OpenTelemetry observability, secret rotation via Key Vault).
Common follow-up questions
Is .NET still Microsoft-only?
No. Since .NET Core (2016) and especially .NET 5+ (2020), .NET is fully cross-platform. It runs on Linux and macOS in production, deploys to AWS and GCP as easily as Azure, and is open-source under the .NET Foundation.
Should I choose .NET or Java for a new enterprise project?
For Microsoft-shop enterprises (already on Microsoft 365 / Azure AD / SQL Server), .NET. For JVM-shop enterprises (already on Oracle / IBM / Spring), Java. Cross-platform tooling and language ergonomics are competitive; the load-bearing decision is integration depth with your existing infrastructure.
What's the difference between .NET Framework and .NET?
.NET Framework (versions 1.x through 4.8) is the Windows-only legacy. Modern .NET (Core / 5 / 6 / 8 / 10) is the cross-platform successor. New code should target modern .NET; .NET Framework gets security updates but no new features.
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