LuLu is the free macOS firewall:

Documentation:
Full details and usage instructions can be found here.

To Build:
LuLu should build cleanly in Xcode (though you will have to remove code signing constraints, or replace with your own Apple developer/kernel code signing certificate).

To Support:
❤  Love this product and want to support it? Please check out my patreon page :)

Mahalo! \