To avoid building large dependencies from source every building may be it will be usefull to have opportunity to not build dependency but just use it to compile only and for linking use pre-built binary. For example, my project has gtkd as dependency. On the first building dub may download gtkd, builds it as a library and then compiles my project and link it with gtkd. But afterwards dub does not build gtkd, but use its source only to compile my project. It may be done through using additional package settings where one can set where interface files are placed. Sorry, if I'm not clear.