FastEnum is the fastest enum utilities for C#/.NET, achieving zero allocation and designed for easy use like System.Enum. It supports .NET Framework 4.6.1+, .NET Standard 2.0+, and .NET 5.0+. It provides performance enhancements when working with enums, with benchmarks showing it to be faster than .NET Core and similar libraries like Enums.NET. FastEnum provides three additional features for enum handling: getting name/value pairs of enum members with Member class, accessing EnumMemberAttribute.Value with a simple API, and adding multiple label annotations to a field using LabelAttribute. Overall, FastEnum is a useful library for optimizing enum operations in your code.