Since late June, I've been building a framework to access any JSON RPC technologies in Delphi.
I'm pleased to announce that the JSON RPC framework is now on Github.
With this framework, it's now much easier to access any JSON RPC technology, as well as most blockchain APIs, since most of them were built upon JSON RPC technologies.
In 2017, with the release of Delphi 10.2 Tokyo, Embarcadero introduced a specialized implementation of the Observer pattern into the System.Classes unit. While it has been in the wild for 9 years, it remains a "hidden" architecture for many, primarily because it serves as the invisible engine behind LiveBindings. Other than live bindings, you can also use the Observer pattern as a way to update component settings to the Windows registry, an .ini file, or persist it elsewhere.
System.Classes