# csharp-developer

> Claude/Codex skill by [@jeffallan](https://omgskills.com/library/jeffallan/index.md) · 12k stars · Updated 2026-10-30

Use when building C\# applications with .NET 8+, ASP.NET Core APIs, or Blazor web apps. Builds REST APIs using minimal or controller-based routing, configures database access with Entity Framework Core, implements async patterns and cancellation, structures applications with CQRS via MediatR, and scaffolds Blazor components with state management. Invoke for C\#, .NET, ASP.NET Core, Blazor, Entity Framework, EF Core, Minimal API, MAUI, SignalR.

Tags: ai-agents, claude, claude-code, claude-marketplace, claude-skills

## Install

```sh
git clone https://github.com/Jeffallan/claude-skills /tmp/claude-skills && ln -s /tmp/claude-skills/skills/csharp-developer ~/.claude/skills/csharp-developer
```

## From README

C\# Developer Senior C\# developer with mastery of .NET 8+ and Microsoft ecosystem. Specializes in high-performance web APIs, cloud-native solutions, and modern C\# language features. When to Use This Skill Building ASP.NET Core APIs (Minimal or Controller-based) Implementing Entity Framework Core data access Creating Blazor web applications (Server/WASM) Optimizing .NET performance with Span , Memory Implementing CQRS with MediatR Setting up authentication/authorization Core Workflow Analyze solution — Review .csproj files, NuGet packages, architecture Design models — Create domain models, DTOs, validation Implement — Write endpoints, repositories, services with DI Optimize — Apply async patterns, caching, performance tuning Test — Write xUnit tests with TestServer; verify 80%+ coverage EF Core checkpoint (after step 3): Run dotnet ef migrations add and review the generated migration file before applying. Confirm no unintended table/column drops.

## Links

- HTML page: https://omgskills.com/library/jeffallan/claude-skills/csharp-developer/
- GitHub: https://github.com/Jeffallan/claude-skills
- Author: [@jeffallan](https://omgskills.com/library/jeffallan/index.md)

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