betterlockscreen
Simple, minimal lock screen.
TLDR
Lock the screen
$ betterlockscreen --lock
Change the lock screen background
$ betterlockscreen -u [path/to/image.png]
Lock the screen, showing some custom text
$ betterlockscreen -l pixel -t "[custom lock screen text]"
Lock the screen, with a custom monitor off timeout in seconds
$ betterlockscreen --off [5] -l