Light at the wrong hour is what wrecks a night worker's sleep.
Not a lack of discipline. Your body clock reads light and decides when you'll be sleepy — so the fix is timing, not willpower. Sunbreak is built around one boundary and three consequences.
Your body temperature bottoms out about two hours before you normally wake. Light before that point pushes your clock later; light after it pulls your clock earlier. Everything Sunbreak says is timed against that estimate.
If your nights are steady, the goal is a full delay: bright light through the first half of the shift, amber and dim on the way home, blackout across your sleep.
If your roster moves, flipping is a losing game. Sunbreak switches to anchor sleep — one four-hour block held every single day — plus naps before shifts. The advice inverts, and the app says so plainly.
Blue-enriched white light suppresses melatonin; amber and dim light largely don’t. And outdoor light on an overcast day still beats the brightest office — a lit workplace does not pay down sun debt.
BPO agents on US hours. Night-shift nurses. Remote workers whose team lives eleven hours away. Anyone whose dentist closes at 5pm and whose mother wants a call at a reasonable hour.
On your device. Sun times are computed locally from your coordinates — no location API, no analytics, no network call needed to open the app. If you make an account, the only thing that moves is your ledger and schedule, and you can delete it in one tap.
Timing guidance only — not medical advice, and never a supplement or medication dose. Shift work carries real health tradeoffs worth discussing with a clinician who knows your history.