I'm currently building my custom Debian image for my Raspi 3B+'s. I'm doing that because I need a 64-bit OS for various reasons (MongoDB 4.0 for example). Luckily I found the great project https://github.com/drtyhlpr/rpi23-gen-image, which makes making such an image child's play.
Now onto the harder part.
I'm trying to get the WiFi working with the custom OS. I already have the package wpa_supplicant installed and copied the config.
However when using for example wpa_cli it complains that wpa_supplicant is not running. So I enabled the service, but that didn't change a thing. Comparing with the Raspbian machine I still have running, I noticed that their service isn't even enabled (Also the WiFi connection is not getting established on my custom system). I know it has to do with the daemon not starting, because when I run "wpa_supplicant -iwlan0 -c/etc/wpa_supplicant/wpa_supplicant.conf" it connects flawlessly and I can connect over WiFi.
So how exactly do I get to autostart the wpa_supplicant daemon on my custom Debian system? Preferably I'd like to use the same or a similar system to that on the offical Raspbian.