Any sufficiently advanced technology is indistinguishable from magic...
Thus we have High Programmers, humans cybernetically enhanced with matter and energy manipulation protocols that "execute programs" powerful enough to violate the laws of reality as understood by the common man.
High Programmers are the only ones that can work the more advanced technology from the Age of the Imperium. Almost a secret society, High Programmers do not share their knowledge with outsiders, although they will work with outsiders to recover ancient technology.
They use the magic-user class from S&W White Box with the following basic changes:
They start with four programs (spells) of 1st level and learn two new spells with each level of advancement of a programming level they can access. Programs are rarely found otherwise. (i may tweak the list)
They do not need to prepare programs in advance. So long as they have available programming (spell) slots of the appropriate level, they can execute the program.
They can only use primitive weaponry, as the energy fields of high powered technology weaponry disrupts their cybernetic energy field.
The replacement of one eyeball with a cybernetic replacement results in a -2 adjustment on all ranged attacks. In exchange, they can "see" heat signatures within 10'.
(work in progress - but a good idea on where I see it going as a White Star class)