I'm copying my explanation for why the dynamic library wasn't built from
my comment on YouTube here for any future reader and hopefully for the
presenter too:
The reason you didn't get the dynamic library is that it is in a
different configuration than the one you built. You didn't need to
modify the sourceLibrary configuration.
I.e.
$ dub build --config=vlangdynamiclib
Or
$ dub build --config=vlangstaticlib
The first configuration is the default, which happens to be
vlangsourcelib. Hence the error.
