&gt;The library is very template heavy and thus most of the code is in the header files so I guess it wouldn&#x27;t change much in this case?<p>Pretty sure the end user is still required to gpl their project if they use your header files.<p>edit: the more I think about this, the sadder I get. You prevented the majority of people from including your software and it doesn&#x27;t sound like you meant to do it. Might be worth a rethink in the next version.