I offer an end to end Xojo code DRM system. Half of it is a Web 1.0 app that acts as the online activation REST API as well as a GUI for managing customers, licenses, and integrations with Stripe and FastSpring.
It is priced for the scale of the package and is meant for professional use. I thought it worth mentioning because I do write Xojo code every day, all day (for the last ten years).
I’m also available for consultation should you desire hands on one-on-one support with your project.
A Web 2.0 version of the panel has been started, but it will be a slow process as it takes a back seat to my daily consulting work and there really is no pressing need.
I can certainly vouch for @Tim_Parnell. His DRM system, TPLM, is fantastic and he’s a top tier coder.
You may be interested in the MBS Xojo Web Starter Kit. As a long-time Xojo Desktop user, but new Web user, it was invaluable in helping me wrap my mind around the concepts. I think it might actually be exactly the type of thing you’re looking for.