Eye breaks that know when you are actually at the computer.
A macOS and Windows desktop app for 20-20-20 eye breaks. What makes it different is that it models presence, tracking idle time, lock state, sleep and wake, and fullscreen suppression, so it does not nag you about a break you were not there to miss.
We blink around 60% less at a screen, and the fix is well known and never remembered: every 20 minutes, look 20 feet away for 20 seconds. The hard part of building the reminder is not the timer.
Horizon is the second attempt at this. The first, LookAway, established the shape: tray-resident, local-only, settings in a JSON file, no accounts and no backend. Horizon rebuilt it around an explicit domain model of a break loop, presence, suppression, an overlay and stats, because the first version's bugs were all really modelling problems wearing timer costumes.
Problem
A plain interval timer fires while you are in a meeting, after you locked the screen, and the moment the laptop wakes with four missed breaks queued up. Each of those makes the app feel broken.
Solution
Presence is a first-class concept rather than a check bolted onto the timer: idle, locked, asleep and awake are normalised into one view of whether the user is actually at the computer, and the break loop consumes that instead of raw elapsed time.
Problem
A full-screen break overlay that appears while the user is presenting to a room, or mid-way through a film, is the one failure that guarantees uninstallation.
Solution
Suppression is its own policy, driven by fullscreen and presentation-like states, and it is allowed to override a due break entirely rather than merely delay the overlay.
Problem
Lock state, idle detection and fullscreen awareness differ per OS and are not fully available through Electron's cross-platform APIs.
Solution
Minimal per-platform native bridges, used only where Electron genuinely falls short, with everything else staying in shared TypeScript. The bridge is deliberately the smallest bridge that works rather than a full abstraction layer.