I have an Azure web app, using ASP.NET 4.7. I reference the Microsoft.Net.Compilers 2.8.2 package, and was successfully able to use C# 7 features.
To make it easier to manage my packages (updating transitive dependencies, etc) I switched from packages.config to using . While this works fine on my devbox, when deploying using Kudu, I get errors for any new C# 7 features I use. For example, inline definition of out parameters.
I look at the logs, and find that it autodetects MSBuild 14, if this matters - but see elsewhere on StackOverflow that Azure has upgraded to MSBuild 15.3 some time ago.