Q: Do Boyum Add-ons use service layer?
Q: Why not?
A: If we begin to use Service Layer it would mean our add-on would only be able to run on SAP HANA and since not all customers are doing so we have decided to continue using the DI-API for now
Q: Do you plan to use Service Layer in the future?
A: Yes, At some point we begin to use it. Service Layer is the right approach to modern service interaction but at the time of this writing (August 2016) service layer adoption rate is not high enough to justify the switch. On top of that Service Layer still have some bug and limitations (Especially around Transactions) that make is less desirable. So only time can tell when technology is more mature and adopted.