Sort of on-topic, I've been using Redshift <https://github.com/jonls/redshift> for years and love it (both windows and linux).
Also thanks, uninstalled flux due to annoyance at lack of full customizability over schedules and hue ranges. ended up finding a more general 'display output' modifier, I'll look into this one though.
The arch wiki[1] has a good entry about redshift autostart as well.
The only other problems I've faced running redshift in the past, were related to geoclue.