Asynchronous Web serving

[fnielsen]

Is your feature request related to a problem? Please describe.
Scholia is here and there using a remote call within a synchronous Web serving, so it will block the server while waiting and

Describe the solution you'd like
Quart, FastAPI, Starlette

Describe alternatives you've considered
Tornado, etc.

Additional context
A possibility would be to add and API, but that would yield even more traffic.