1. Do not apply power to the board
2. Attach the board via serial to your system, ensuring power is still not applied
3. Ensure the serial shows up in /dev/ttyUSB*
4. nix run github:matthewcroughan/visionfive-nix#flashBootloader /dev/ttyUSB0
5. Apply power to the board

even though I'm doing

                    -r ${jh7100_recovery_binary} \
                    -b ${jh7100_secondBoot} \
                    -d ${jh7100_ddrinit}

Which really does flash the original binaries from their releases, it just nukes whatever uboot proper you happen to have on the board

[0;nixos@nixos: ~nixos@nixos:~]$ rfkill

[0;nixos@nixos: ~nixos@nixos:~]$ systemctl status wpa_supplicant.service 
● wpa_supplicant.service - WPA Supplicant instance
     Loaded: loaded (8;;file://nixos/etc/systemd/system/wpa_supplicant.service/etc/systemd/system/wpa_supplicant.service8;;; linked; vendor8;;>
     Active: active (running) since Thu 2021-12-23 20:11:44 UTC; 2min 49s ago
   Main PID: 907 (wpa_supplicant-)
         IP: 0B in, 0B out
         IO: 252.0K read, 0B written
      Tasks: 4 (limit: 7844)
     Memory: 2.3M
        CPU: 158ms
     CGroup: /system.slice/wpa_supplicant.service
             ├─907 /nix/store/h8xcpjsipl1hvzz6bnkwmdlgajzclj77-bash-5.1-p16-ris>
             ├─911 grep -q ^ACTION=add
             ├─912 /nix/store/h8xcpjsipl1hvzz6bnkwmdlgajzclj77-bash-5.1-p16-ris>
             └─913 udevadm monitor -s net/wlan -pu

Dec 23 20:11:44 nixos systemd[1]: Started WPA Supplicant instance.
Dec 23 20:11:44 nixos wpa_supplicant-start[907]: Waiting for wireless interfaces