This as a variation of previous (linked) tracker FHIR-28909.  Instead of asking for a cardinality change for a normative property, instead I'm going to describe our use case and leave the solution up to the WG.

We have multiple different software products that are "behind" a FHIR server.  We need a way to communicate each of those software products to the consumer of the CapabilityStatement (ONC/Lantern in this case).

CapabilityStatement.software is 0..1, so that doesn't work.  

Possible options:

1. Update CapabilityStatement.software to be 0..*.    This was previously rejected in FHIR-28909.
2. Create a new property (CapabilityStatement.software2 that is 0..*, and deprecate CapabilityStatement.software.
3. Create a standard extension that represents the exact same thing as CapabilityStatement.software, but is 0..*.
4. Something else the WG would like to suggest.

I personally have a strong preference that there is only one way to do something like this in the spec, otherwise you'll get divergence.  Having multiple properties and extensions that mean exactly the same thing, just with different cardinalities seems undesirable.

Also, while we are here, it would also be useful to add another property of type Identifier within whatever we create that is a unique ID for the software product.  This may not be broadly applicable, so this might be extension space.  For example, ONC has a listing of certified software products:  https://chpl.healthit.gov/#/search.  Search for Epic, and you'll see entries that list the version, developer, product, and a unique CHPL ID.  This new identifier would be to represent that CHPL ID.  We could make this US Core, but I know there are other jurisdictions in EU that have a similar registry of products with identifiers.