Chapter 1 - Identity
Identity is denoted via a URI
Generally a URI will be an HTTP URI following 5 star linked data principles, and w3c standards.
Authentication, credentials, reputation and social aspects are handled orthogonally of reputation. Authentication being the verification of a particular identity. Credentials and social aspects are data points tied to that identity. Reputation is derived by algorithm from all of the above.
In gitpay, WebID is used for identification, which is a hash HTTP URI that denotes a person. Other systems based on URIs can be used and are interoperable too, provided that they follow the requisite spec.