Sleep

In Survival Industry, which makes use of the "Somnia" mod, everything you know about sleeping no longer is. You can't plop down a bed in the middle of a field, and expect to avoid monsters. Your sleep will not stop the night from passing; it simply passes faster... and everything that spawns will still come after you, even if you're asleep. Your hunger will continue to progress. On the positive side, any processing you start will continue to operate while you're asleep, so there is that; you can start a furnace project, go to sleep, and when you wake up, a night worth of progress will be shown in the furnace.

In addition to sleeping no longer being a "turn mobs off" feature, you are now required to sleep. As you continue to play the game, you have a fatigue timer (shown at the bottom-right of the screen) which shows how tired you are. In order to be tired enough to sleep, your fatigue timer needs to be, at minimum, a level of 20. You can stay awake beyond this, but once the timer reaches 70, bad things start to happen, such as mining fatigue, nausea, and even poison (these events are short and temporary; they serve as a reminder that you're tired).

Once the fatigue timer reaches 100, you will be permanently slowed, weakened, and with mining fatigue. Once you've slept enough for the timer to drop under 100, you'll have your normal speed and stats back, but it is still highly recommended you keep sleeping until the timer reaches 0.

At the moment, there is no way to sleep at night if your timer is under 20, so once you go to sleep, don't try waking up, or you won't be able to sleep again.