undefined parse transform 'tools'

[dgud]

Yes it does, which 'make' sets up for you.
See the makefile if you need to know.
What I mean is that it's more simple to use make
than invoking erlc on your own.
The parse transform is used for language strings in translations.
So not needed for your plugin in the beginning but needed for compiling all the other wings src files. Migth be needed when including wings.hrl I don't remember.