Good to see open source alternatives to the awful Logitech software. I only realized how bad the Logitech software is after switching from a G502 with on-board memory to an MX Master mouse that does not have on-board memory and needs to have the app constantly running in the background to use the gestures. Personally I've been using BetterMouse on macOS with my MX Master, although it's not open source.

https://github.com/pwr-Solaar/Solaar has been around for quite some time and works well.