Understanding "Attach Project"

I made a presumption and then realized I really should check on it. I have a project in that the project directories are like:

ProjectX
 core
    things
  rules
    plugins
      plugin1
      plugin2

where plugin1 & plugin2 are independent projects so they should not be compiled into the main ProjectX. To prevent this I told GoLand that each one is a separate project (and each one has it's own main package name and function called main) and then when asked "attached" the plugins as projects. Is this a valid way to separate out the code so they don't get compiled as part of ProjectX or do I need to do something else extra like move them completely out of the ProjectX directory structure?