​In those days, I knew / knew of some of Steve Wards' guys in the RTS lab working on Trix (Wayne Gramlich [late of CMU -- the connection], Jack Test, Tom Teixeira, Terry Hayes, etc...).

Wayne brought some of the CMU hacks to MIT and sent us some of theirs such as the Chaos code.   For instance, my >>guess<< is that fsck came to MIT via that connect, since Ted wrote much of it at CMU.

FYI: I would later do a really crappy job of hacking the Ritchie C compiler to work with an experimental chip we got from Moto (what would become the 68K) - it generated correct code (just barely) but worked.   It was from that connect I learned that Ward's guys did a >>much<< better job for Trix project (and maybe used the Johnson compiler - but could target a couple of different micros).  I remember I switched to their compiler when I got it (from Jack I think).  I believe I even still have 9-track tape of it somewhere in my basement.

Clem