A very simple design is light, working off a timer. A simple "trouble light" or "drop light" that mechanic used to use works well and are inexpensive. The little timers are only $10 or so and typically sold to control Christmas lights.
I do not push my hens through the winter. I don't have the light on much. It's only 40 watts, but that's enough. I have it come on at 5 am. It goes off at 4:30 pm so as not to catch them unaware of the approaching darkness. That's their cue to go to the roosts. Our winter days are very, very short. Supposedly, lights should illumine for 14+ hours for maximum egg production, but I think 12 hours is enough. They need to sleep, rest and use their energies for keeping warm. Production drops some, but nothing horrible.