pyparsing was recently updated to 3.0.0 which broke gixy. It hits parsing errors on even a trivial configuration such as the one shipped with the nginx package:

[nginx_parser] ERROR Failed to parse config "/etc/nginx/nginx.conf": char 12 (line:2, col:1)

I've tested with the latest pyparsing 3.0.7 and it's still broken. Since gixy isn't actively developed/maintained anymore, this is unlikely to be fixed. Development will hopefully be revived since it's quite useful...

I don't think there's an easy fix without familiarity with the code. This probably needs to be dropped from the repositories for now. It's straightforward to get it working with requirements.txt via a dedicated Python virtualenv, which as far as I know doesn't really work for an Arch package:

https://github.com/disconnect3d/gixy/commits/patch-1