This was an interesting read. It's always educational to me to see how people use Angular with IRIS as someone who started using Angular recently too.
If you want to refine your code, then I would recommend migrating away from BehaviourSubjects and decorators to using Signals (in fact, I would say to minimize using RxJs if you can get away with it while we wait for more widespread javascript native observables support). Similarly, Zoneless with OnPush change detection seems to be the way of the future.
If you are taking suggestions on future directions for this series then I'm interested to see how Auth Guards can work with IRIS to secure REST endpoints.
It's weird that your extent size is showing up as 3521840 but your SELECT COUNT(*) says 49468
Maybe you need to rebuild pxfactidIndex?
Thank you for making this post Ben.
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