For the first time since the old Alpha days, I now have the entire VAMP stack running natively on OpenVMS.
The last piece of the puzzle was always MySQL/MariaDB which has lacked a working OVMS port for a number of years, and has never had a working x86 port.
We now have an early (but working) release here, https://github.com/issinoho/vms-mariadb
About time!