It was whatever they were shipping in the early 1990s, CLI tools. It cross-compiled to mangled C++ which made it un-debuggable outside of inserting print statements, compile turnaround for even a small program was 20 minutes on a reasonably speedy DECstation (now pair this with the debugging comment), it used some node-locked licensing scheme where, when the compiler crashed, which it did a lot, it left the lock active so someone with root access had to come in and remove it, and lots, lots more that I can't remember. It's a pity camera phones didn't exist back then or I'd have a photo of a whiteboard with a drawing of the Eiffel tower, broken in half in the middle, and a figure in a noose labelled "Meyer himself" hanging from it.

Nice language, but seriously cursed by unusable tooling.