How to define a profile that extends tabular-data-package?

[peterdesmet]

We are aiming to define a JSON Schema for camera trap data that builds upon tabular-data-package, i.e. adopting all the properties of tabular data package, but adding more specific ones for camera trap data. This is similar to:

Tabular Data Package builds directly on the Data Package specification. Thus a Tabular Data Package MUST be a Data Package and conform to the Data Package specification.

It is unclear to me how that is defined in the JSON Schema. In the tabular data package json schema I see no reference to data package json schema. Is everything just copy/pasted?