# Build Modern C\# and .NET Applications

Complex .NET projects require consistent architecture, asynchronous design, performance discipline, and reliable tests. This skill provides focused C# guidance and verifiable implementation steps.

## Install

```bash
npx skillstore add sickn33/csharp-pro
```

## Metadata

- Status: approved
- Slug: sickn33-csharp-pro
- Skillstore revision: r2
- Version status: missing
- Tree hash: 0407201575ce418c0d67bb887c049a99fbbc02d968cfa446c2bbb20c499f507c
- Author: sickn33
- GitHub username: sickn33
- License: MIT
- Repository: https://github.com/sickn33/antigravity-awesome-skills/tree/main/skills/csharp-pro
- Ref: f9e2c34b4f19c7f3e6b0a1e93227b5f77cc12526
- Supported tools: Claude, Codex, Claude Code
- Audit status: complete
- Agent install advisory: allowed
- Manual install advisory: allowed
- Artifact signature: available
- Audit attestation: unavailable
- Human verification: not\_verified
- Risk factors: external\_commands
- Quality score: 78
- Quality tier: bronze
- Public page: https://skillstore.pages.dev/skills/sickn33-csharp-pro
- Manifest: https://skillstore.pages.dev/api/skills/sickn33-csharp-pro/manifest

## Capabilities

- Designs C\# solutions using records, pattern matching, nullable reference types, and other modern language features.
- Guides ASP.NET Core, Entity Framework, Blazor, and microservice implementations.
- Applies SOLID principles, composition, error handling, and enterprise architecture patterns.
- Improves asynchronous and concurrent code using async, await, and the Task Parallel Library.
- Creates testing and benchmarking strategies with common .NET tools.

## Use Cases

- Modernize a C\# Codebase: Update older C\# patterns with nullable types, records, pattern matching, and clearer error handling.
- Design a .NET Service: Plan service boundaries, dependency injection, persistence, asynchronous workflows, and testing for an ASP.NET Core application.
- Improve Reliability and Performance: Review concurrency, allocations, tests, and benchmarks to identify measurable improvements.

## Prompt Templates

### Explain a C\# Feature

```
Explain [C# feature] for a beginner. Show when to use it, common mistakes, and a small practical example.
```

### Refactor Existing Code

```
Refactor this C# component for readability and nullable safety. Preserve behavior, explain each change, and propose focused unit tests: [component].
```

### Design an ASP.NET Core Feature

```
Design [feature] for ASP.NET Core using [constraints]. Include boundaries, data flow, failure handling, asynchronous behavior, dependencies, and a testing strategy.
```

### Analyze Performance and Concurrency

```
Analyze this .NET workflow for blocking, contention, allocations, and cancellation issues: [workflow]. Propose measurable changes and a BenchmarkDotNet validation plan.
```

## Limitations

- The skill provides guidance and generated code but does not execute or compile projects.
- Performance recommendations require measurement in the target environment.
- Framework and package compatibility depends on the selected .NET version.
- Generated solutions require project-specific testing, security review, and deployment validation.

## Best Practices

- Provide the target .NET version, framework versions, constraints, and expected behavior.
- Request tests and validation criteria with every implementation change.
- Measure performance before and after optimization using representative workloads.

## Anti Patterns

- Do not request architecture without explaining domain boundaries, scale, and operational constraints.
- Do not accept asynchronous changes that omit cancellation, failure handling, or end-to-end propagation.
- Do not apply advanced language features when simpler code communicates intent more clearly.

## Security Audit

- Audited at: 2026-07-23T22:02:33.458\+00:00
- Summary: The only static finding is a false positive caused by Markdown backticks around a documentation path. The prompt contains no executable code or malicious instructions.

## Stats

- Views: 95
- Downloads: 30
- Favorites: 0
- Popularity score: 0