Sleep timer

Fall asleep to your mix without leaving the computer running all night at full tilt.

Click the moon icon in the toolbar to open the sleep timer. Set how long from now (or a specific time of day), pick what happens when it ends, and start it — a countdown shows next to the button while it's running.

What happens when it ends

Action	What it does
Stop all sounds	Pauses the mix. Nothing else changes.
Turn off the displays, keep the sound playing	Switches your monitors off while the mix keeps going — for a dark room without stopping the ambience. Any mouse move or key press wakes them back up; audio is never touched.
Put the computer to sleep	A 30-second warning first, with a cancel option, since this is harder to undo mid-action.
Shut down the computer	Same 30-second warning.

It survives closing the app

A running timer is remembered even if Noctívago restarts (including for an auto-update) — it comes back with the correct time still remaining. If it would have gone off while the app was closed, it only still acts if that was recent; a long-stale timer is dropped rather than, say, shutting your computer down the instant you reopen the app hours later. The "turn off displays" action specifically never fires from a stale/closed state at all — if you're back at the app, you're clearly at the machine, so blanking the screen then would just be annoying rather than useful.

Presets and a time-of-day mode

Quick preset buttons (15m, 30m, 45m, 1h, 1h30, 2h) speed up picking a duration. An "At a set time" mode counts down to the next time the clock hits a time of day you choose, instead of a plain duration from now.