Cool, thanks for the summary! The user-defined indexes sound particularly intriguing.

The documentation page alludes to payroll, audit and decision support applications -- have you implemented one or more of those already? I have been compiling a list of known uses for bitemporality in the Crux docs which you are more than welcome to borrow from:

https://juxt.pro/crux/docs/bitemp.html#_known_uses

It is great to see all this new enthusiasm for temporal databases now that they are finally viable, decades after all the major research happened :)