What / why is Roslyn “needed” in /bin folder of Asp.Net

Question

There are a bunch of related questions on this, though most of the answers define Roslyn and/or provide a \"fix\" to some issue (exe, with hosting prov

Answer 1

This is taken from MSDN forum.
https://social.msdn.microsoft.com/Forums/vstudio/en-US/442b100a-2b88-4ac4-b655-0c1345791f15/roslyn-cscexe-web-api-2-on-hosting-server?forum=msbuild

I have noticed a minor drawback to uninstalling this package:

https://www.nuget.org/packages/Microsoft.CodeDom.Providers.DotNetCompilerPlatform

Some of the new C# 6.0 language features if used in Views (MVC project) will not compile. Many of my views use the ?. null checking operator for accessing Model properties. All of these views now return errors on my Godaddy hosted MVC 5 application.

This error occurs because Views (by default) are compiled at runtime using the .NET pipeline (not pre-compiled).

To resolve this issue, simply uncheck the "Allow precompiled site to be updatable" option in your publish profile settings. This should pre-compile your views and allow your C# 6.0 (Latest version of Roslyn Compiler) to run like a champ.

Just wanted anyone looking at this question to know the ramification of uninstalling it and why its there in the first place