I'm going to build a new copy (of Ramrod) as an ST floppy image file, then try that in an Emulator - we shall see.
Bogeydev was written by Colin Dooley (Aka. Fungus, as in Fungus The Bogeyman - he changed his name, accounts could never work out that his middle name was "The" hence middle initial was "T.") for internal use at Gremlin Graphics. It was a shell written and running on an ST from which you could launch a text editor (Tempus) an assembler (DevPac) then transmit the object file (without symbols) to a remote machine (ST or Amiga) via the parallel cable.
On the remote machine there was just a small bit of code running from a floppy (512 bytes I recall, just a boot sector which left the other 511.5K available) that listened to the parallel interface and looked after the basics on the target machine.
The file transfer was hash totalled in 256 byte chunks so sections could be skipped to speed up the transfer. Once transfered a debugger could single step code, watch/edit memory, set breakpoints etc etc.
SNASM provided the same feature set, except it included a bundled assembler, was PC based, and was mainly used with BRIEF (text editor). I could never work out why SNASM used a SCSI interface to over complicate things - that made things expensive, when prior to that parallel leads and serial cables were fine. But then I guess, Bogeydev was dealing with object files circa 30-60K, SNASM 512K ... so I guess as games got fatter the interface speed needed to. After all computers are never fast enough
There was also a system used by all the 8-bit guys on C64, Spectrum, Amstrad, Atari400/800 etc. But I don't think that had remote debugging, just editing and assembling then firing down a shared high speed serial interface from the Pinnacle (I recall, possibly a CP-M box) server to the target machine. That allowed 8-bit development with the aid of a hard drive I guess.
You have to remember that to all intents and purposes all the early computers were effectively consoles with keyboards. Their operating systems were either too basic or too heavy on resources. Hence remote development was the only option, really, once you had killed the operating system - it was a no brainer.