Coding Guidelines for C# (up to v14)

See the landing page at https://www.csharpcodingguidelines.com

Use the guidelines as an agent skill

The csharp-guidelines skill makes AI coding agents apply these guidelines when they write, review or refactor C# code. This repository is a plugin marketplace for Claude Code and GitHub Copilot CLI.

Claude Code:

claude plugin install csharp-guidelines --marketplace dennisdoomen/CSharpGuidelines

GitHub Copilot CLI:

copilot plugin marketplace add dennisdoomen/CSharpGuidelines
copilot plugin install csharp-guidelines@csharp-guidelines

How to create the PDFs

From the root of the repo, run:

.\build.ps1        # Windows
./build.sh         # macOS / Linux

This compiles all guideline rules into two PDF files in the Artifacts folder:

• CSharpCodingGuidelines.pdf — the full guidelines document
• CSharpCodingGuidelinesCheatsheet.pdf — the two-page cheat sheet

Pandoc is downloaded automatically on first run. Google Chrome must be installed for PDF rendering.

How to preview the site locally

Run the following script from the root of the repo:

.\launch-website.ps1        # Windows
./build.sh LaunchWebsite    # macOS / Linux

This installs Ruby 3.3 (if not already present), runs bundle install, and starts the Jekyll development server at http://localhost:4000. The server monitors for changes when using the --incremental flag.

Prerequisites

• .NET 10 SDK
• Google Chrome (for PDF generation)
• Ruby 3.3 is installed automatically when launching the website locally

Troubleshooting

• Do you receive an error around jekyll-remote-theme and libcurl? See this issue on the pages-gem repo.
• Do you receive an error Liquid Exception: SSL_connect returned=1 errno=0 state=error: certificate verify failed? Check out this solution in the Jekyll repo.