This document discusses versioned triple pattern fragments (VTPF), a proposed interface for querying RDF archives at web scale using triple pattern fragments. VTPF adds versioning features to TPF to support version materialization, delta materialization, and version queries over archived RDF data. It introduces a "version" vocabulary to represent versions as separate datasets and includes human-readable and machine-readable hypermedia controls for the different query types. While progress has been made, an open challenge remains to standardize the mapping to RDF archive query languages and appropriate backend storage solutions.