                 facebookConnectError: ErrorEnvelope? = nil,
                 fetchActivitiesResponse: [Activity]? = nil,
                 fetchActivitiesError: ErrorEnvelope? = nil,
+                fetchBackingResponse: Backing = .template,
                 fetchCategoriesResponse: CategoriesEnvelope? = nil,
                 fetchCommentsResponse: [Comment]? = nil,
                 fetchCommentsError: ErrorEnvelope? = nil,

    ]

    self.fetchActivitiesError = fetchActivitiesError

    self.fetchCategoriesResponse = fetchCategoriesResponse ?? (.template
      |> CategoriesEnvelope.lens.categories .~ [

  func fetchBacking(forProject project: Project, forUser user: User)
    -> SignalProducer<Backing, ErrorEnvelope> {

    return SignalProducer(value: fetchBackingResponse)
  }

  internal func fetchDiscovery(paginationUrl paginationUrl: String)
