Docker is meant to be a platform for running HW independent SW. The Evok depends on the UniPi ModbusTCP server, which depends on the kernel module, so it is pretty much down to the hardware kind of application (heavy SPI and I2C communication). You can "enclose" your application with certain Evok version and configuration into Docker container, but it will still require manual work on the Docker host to make it transportable accross different UniPi controllers.
I have added this feature via a config file switch to the Master branch of EVOK. As I've mentioned before it may take a while to propagate to our releases and debian packages, but you should be able to test it out manually.