csharp-performance

name	csharp-performance
description	Review C# and .NET code for performance, memory, allocations, LINQ overhead, async scalability, data access, EF Core queries, concurrency, throughput, benchmarking, profiling, and scalable implementation choices.
metadata	{"short-description":"Performance review for C# code"}

C# Performance

Use $csharp-tutor mode=performance.

Treat all user text after $csharp-performance as the code, query, project, or performance concern. Use the main csharp-tutor skill as the source of truth.

Load these csharp-tutor references when useful:

• references/performance-review-map.md
• references/modern-dotnet-patterns.md
• references/aot-guidance.md
• references/tooling-and-analyzers.md
• references/project-inspection.md
• references/framework-guidance.md
• references/verification-checklist.md

Avoid unsupported performance claims. Recommend measurement, profiling, or BenchmarkDotNet when the performance tradeoff is not obvious.

Standalone Guidance

• Core rule: Keep the answer centered on the concrete performance decision, failure mode, or contract.
• Avoid: Giving generic C# advice without tying it to the performance concern.
• Minimal example: var ids = users.Select(u => u.Id).ToHashSet();