The Multiprocessing Developer Kit was distributed at MacWorld Boston
1995 and was a collaboration between Apple and Daystar Digital. It
allowed developers to write applications that would work on PowerPC
systems with multiple processors. (They didn't exist yet.)

This would have been the first step towards making pre-emptive
multitasking applications under Copland, as Apple was not going to
make the System 7-era Thread Manager support pre-emptive multitasking.

Compatibility
Architecture: PPC

"The MP API will run on all current and planned generations of the
PowerPC-based Mac OS -namely, System 7, Copland, and Gershwin"