Not implemented. There is no profile object kind, no profile table, and no assignment surface anywhere in the platform. This entry records a design direction so it is not reinvented, not a capability you can use.

The idea: a reusable assignment unit — a set of permission grants plus default environment grants — that an org administrator attaches to a subject in one step, instead of writing the same twenty grants for every new hire.

It is deliberately distinct from an audience, which is a typed group used for routing and bulk targeting. A profile would be a typed role held by one subject. The two answer different questions: "where does this event fan out to?" versus "what can this subject do?".

Until it ships, the supported path is explicit capability grants, org roles and team membership. See permission.