Solar engineer

The solar engineers were a caste of scientists on ancient Gallifrey.

The solar engineers answered to the Gallifreyan Council for funding, but could order around the biological engineers; it was on the solar engineers' orders, as part of the ongoing attempt of the early spacefaring Gallifreyans to set themselves up as gods to "lesser species", that the biological engineers created the Calculating Animals with Tails, or cats.

Rassilon and Omega were both originally solar engineers before they used their knowledge to use the detonation of a black hole to invent time travel, fundamentally overhauling Gallifrey's society and its place in the universe. Ironically, though they had originally been among the few solar engineers who resisted the "become gods to the lesser races" plan in favor of worrying about the future of Gallifrey itself, Omega and Rassilon's research was what allowed the Gallifreyans to genuinely become nearly godlike. (PROSE: The Legacy of Gallifrey)