This is Read-Eval-Print-λove v003, by @fogus
I had high hopes for FACTOR but it seems to have kind of gone dormant of late.
They haven’t made a stable release in a while, but it looks like Factor is still quite active. Their Github repo is buzzing with activity.
I really liked Factor – it was the first open-source project I got involved in. I believe Slava is working on the Swift compiler team now though.
Compiling and parsing words implemented as primitives, no memory and no rstack? I’m sorry but that ain’t no Forth to me, that’s a glorified RPN calculator.
Here is a toy Forth system I’ve written. (Maybe I should start writing blog posts about my toy projects?)
If you wish to learn the Forth way of thinking, I can recommend And so Forth… by Hans Bezemer (HTML, PDF). I should probably post it.