Slackware :: Avoiding Redundant Installations And Pkgsrc

Slackware is very stable and very geek-friendly. I happen to love it... Unfortunately, I've found it unsuitable for day-to-day stuff in recent years, because it doesn't have a whole lot of software in its repos - and installing stuff from source can quickly lead you into dependency.

But pkgsrc has a vast amount of software in it, and can run on Linux. So it could be a solution, right?

The problem with pkgsrc is that the dependency resolution doesn't recognize stuff installed through standard Slackware packages. If you try to compile Gnash with it for instance, it will drag in Firefox and waste a few hours compiling that, even if you already installed Firefox through pkgtools. So with a default setup, pkgsrc is suitable for building on a very minimal Slackware system, but not for extending a preexisting Slackware desktop with Xfce and Firefox and whatever.

Is there any way of changing this, so that pkgsrc registers preinstalled binaries as providing whatever dependency? Or is that not possible? If not, is there any other system that could provide dependency resolution for compiling stuff?