Issue: During VSTS agent build, you encounter errors similar to this one. Most likely during builds involving Fody:
Error: Fody: An unhandled exception occurred: Exception: Out of memory
Cause: This appears to be a bug related with Mono/Cecil/Fody
Solution: The current solution is to change Visual Studio for Mac or Xamarin's preference > .NET Runtimes default to "Mono 4.8.0." Please contact our support so we can carry out the setting change for you.
Out of Memory in Xamarin Studio and Visual Studio for Mac - Github Forty Issues