Joyful Design Patterns — code samples

Runnable code samples for the Joyful Design Patterns book series. Every pattern in the books is shown in real, open-source code you can clone and run — not a class diagram and a toy example. This repository holds those samples.

The code runs against Herald.OSS (Apache-2.0), the structured-logging library used throughout the books.

What you need

The .NET 10 SDK — get it at https://dotnet.microsoft.com/download, then check it:

dotnet --version   # should start with 10, e.g. 10.0.204

That's the only requirement. The samples are single-file .NET 10 apps; the first run downloads the library from NuGet for you.

Run a sample

Every pattern has one self-contained file, patterns/<pattern>/demo.cs. Run one from the repository root:

dotnet run patterns/01-strategy/demo.cs

One file, one command, real output. The first line of each sample, #:package Herald.OSS@0.12.8, is a .NET 10 file-based-app directive that pulls the package on first run — no project file, no manual install.

Go deeper

• Herald.OSS — clone, read, and build the actual library every sample uses: https://github.com/mmpworks/Herald.OSS
• Herald DemoApp — a dotnet tool that runs a live Herald pipeline with an embedded viewer in two commands: https://github.com/mmpworks/Herald.DemoApp

  dotnet tool install --global Herald.DemoApp
  herald-demo

License

Apache-2.0 — see LICENSE. The samples are free to read, run, and adapt.