This is yet another repo dedicated to design patterns in C#. This e-book will focus on the Gang of Four (https://en.wikipedia.org/wiki/Design_Patterns) patterns and other things such as SOLID, Dependency Injection and composition over inheritance.
Anyone can contribute by sending a PR.
As with many things in programming, pattern implementations can be pretty subjective. The main takeway is that each pattern solves a particular pain point commonly found in modern object-oriented programming.