This is a dockerized version of the release posted by Kenxo which can be found here.

whmcs-v-8-3-0-r1-full-with-license-key

Credits go to him for the original files......

This script will install those exact files in docker.

Mysql data is persistent
downloads directory is persistent
attachments directory is persistent
templates_c directory is persistent
cron is fully functional within the docker container
downloads, attachments & templates_c are outside the web directory

All modules and requirements are installed & working.

Script is automatic, follow the instructions it gives you.

Enjoy!!!