Kali is nuking my gateway setting

I come from a bygone era where UNIX didn't have a billion supervisors changing state under your feet. I just want to manually do everything like the old days.

I set my IP and default gateway and my connection works. Then something mysterious from the bowels of nuLinux deleted my gateway setting, killing my connection.

I then have to "route default gw ..." to get my connection back. Every friggin minute. There is no process named dhcp* or whatever so I don't have a clue what's nuking my gateway.

I'm not even keen to know what's going on; I just want it to stop. Can anyone help me?

You need to set up a WPA Supplicant file that your OS will read at boot up and use your chosen settings when it launches WiFi

Manual method if you like CLI is down page quite a way;
https://wiki.debian.org/WiFi/HowToUse