I have been working on creating a JSON API for my website using the specification found at jsonapi.org. There are a few libraries that help, but they seem more complicated than necessary to use. I am developing a library that integrates directly with the eloquent model class, and requires almost no effort to use on behalf of the already overworked programmer. However, the JSON API makes no mention of composite keys. In regard to ID's it says, "Within a given API, each resource object's type and id pair MUST identify a single, unique resource. " Does anyone have any suggestions for handling composite keys?