Measuring time without moons or seasons

So in my world there is one sun, no moon, a starry nightsky, and it takes place in a Mediterranean sized area near the equator so seasons basically don't exist. There is no religious reason or anything to count "weeks", either, so on a basic level people count in days, but then above that years, though I don't know with what.

I was thinking the sun might pulse extremely noticeably sometimes which could be used to measure years (would be dope because there's firefly people who could react to that pulsing), but besides that I really couldn't think of anything annual that could be used. Any ideas?