Configure static wlan0 in /etc/network/interfaces

Get wpa-psk by running wpa_passphrase MyNetwork MyPassphrase.
/etc/network/interfaces should be chmod 0600 if you put the wpa-psk there

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo wlan0
iface lo inet loopback

iface wlan0 inet dhcp
  wpa-ssid MyNetwork
  wpa-psk a2d024861ef90117c47083c9252d1e9c107c7cc6ab938cd08349c9192d444d2f