To instantly share files on the network - only one thing is required - a caddy.
Install the package from the official repo.
sudo pacman -S caddy
Copy the files you want to share to the Public folder in your home (Public is the english name - localized versions will most likely work as well) - and remember to surround folder path with double quotes if there’s a space in the name.
Then run this command (you can of course script it)
caddy file-server --root "/home/$USER/Public Files" --listen :8080 --browse
Open a browser on any computer connected to your network and enter
You are of course not limited to use the Public folder - in fact it could be any folder that makes sense - just change the –root argument to match.
Also remember to use a non-priviledged port - that is any port between 1024 and 65535.