Spotty is a somewhat spotty implementation of Spotify Connect for the Squeezebox and other compatible music players running Squeezelite or Squeezeplay connecting to a Logitech Media Server.
Spotty exposes your Squeezebox as a Spotify Connect client. Alternatively you can use any Squeezebox Controller, compatible mobile app or the Logitech Media Server web interface to play music from Spotify.
The Spotty plugin is known to run fine on recent Windows, macOS, and Linux on x86_64, and many ARM platforms (including Raspberry Pi, many NAS devices, rock64). Some platforms which are not supported out of the box can probably be supported by compiling the spotty helper application yourself - or some friendly community member. It's based on the great librespot project.
Most aspects of the Spotty configuration can be configured in LMS directly, in Settings/Advanced/Spotty.
IMPORTANT: on some systems you might need to tweak a firewall, or configure your container to make things work. Please make sure you allow Spotty, and in particular its helper application which you can find in its Bin folder, can reach the internet on ports 80, 443, and 4070! You might have to add 5353/UDP to the list if you experience problems seeing your devices as Spotify Connect endpoints.
Using the spotty helper and the librespot code to connect to Spotify's API is probably forbidden by them. Use at your own risk.