I spent a full week of vacation time once playing around with Factor. It was a real trip -- I'd been reading some of the Forth books the month prior for the first time, and reading over jonesforth, and then when I began using Factor the experience felt very civilized. Scripting-language feel, surprisingly good performance, and very clean refactors.

It's not the same feel as the "virtuous abstraction" of macros in, say, Common Lisp -- Factor has some very general abstractions that aren't always free (whereas macros can be near-free. And though Factor has macros, I remember feeling that I was somehow fighting Factor every time I wrote one). And the documentation, through the REPL/docs browser that comes with Factor, is almost terrifyingly complete ... and presented in a cross-platform GUI built on OpenGL.

In short, Factor is one of those projects so all-encompassing and impressive that you briefly fear that someone has "won" at hacking, and that the pastime will shortly be retired.

But it has no package manager.

It seems amazing. They've solved so many other problems so beautifully. Why not solve the one problem that (empirically, seems as though it) controls the growth of open-source programming languages?

It's not a trivial thing, of course, to build a package manager. But it's amazing, given the talents who have made Factor what it is, and what they've accomplished, that no one has taken it on.