I’ve enjoyed using the Simple Alarm Clock on F-droid, importantly for me, it requires you to hold down the shut off button for a couple seconds which helps prevent me from accidentally shutting off my alarm instead of snoozing it. Only downside for this app and possibly others is that they may not function if your device OS updates in the middle of the night.
This is my go-to linux music player purely and simply for the fact it supports winamp classic skins