Ah, and just as a warning to you and anyone else who might be using this new Device API, there are some breaking changing coming down the line 
Whenever Milo 0.5.0 is released and Ignition updates to it there will be some required changes to your Device implementations. You can get a feel for what’s changing here: Update opc-ua-device example for upcoming Device API changes by kevinherron · Pull Request #43 · inductiveautomation/ignition-sdk-examples · GitHub
and the corresponding change in Milo here: Remove AbstractLifecycle from ManagedAddressSpace class hierarchy by kevinherron · Pull Request #627 · eclipse/milo · GitHub