---

name: csharp-standards description: Modern C# 14 / .NET 10 coding standards and best practices. trigger: "**/*.cs" allowed-tools: Read, Write, Edit, Bash, Grep, Glob

C# 14 / .NET 10 Coding Standards

Modern C# development standards based on CONSTITUTION.md.

Philosophy: Defensive Coding | Strict Analysis | Pragmatic DDD | Vertical Slices

Goal: Zero warnings, zero allocations on hot paths, type-safety, immutability.

Topic Files

Quick Rules

• sealed internal by default
• Records for data, Value Objects for domain primitives
• ErrorOr instead of null or exceptions
• Collection expressions [] not new List<T>()
• TimeProvider not DateTime.Now
• Shouldly not FluentAssertions (commercial)
• K&R braces on same line, always mandatory

For detailed quick reference, see quick-ref.md.

Source of Truth

The authoritative source for all rules is CONSTITUTION.md in the repository root.

Project Templates

When user asks to update, sync, or initialize project configuration files, use these templates from the plugin:

Commands user might say:

• "обнови мой editorconfig по стандартам"
• "sync my Directory.Build.props"
• "initialize project with C# standards"
• "update config files from templates"

Workflow:

1. Read the template file from plugin's templates/ directory
2. Read user's current file (if exists)
3. Show diff or ask before overwriting
4. Write the updated file

Load specific topic files based on task context.