Usage of reserved keywords as variable identifier CS-R1030
Bug risk
Major
Keywords such as async and await have been introduced in C# 5.0 and are called contextual keywords. Contextual keywords have special meaning only in a limited program context and can be used as identifiers outside that context. However, it is recommended that you do not use such keywords as identifiers to avoid confusion.
Bad practice
var async = true;
Recommended
var isAsync = true;