Define User has id, name.

Define Dash has profile, timeline.

Define AuthErr as one of InvalidCreds, Locked.

Rule fetchDashboard given u, produce. It performs io:
  Start profile as async ProfileSvc.load(u.id).
  Start timeline as async FeedSvc.timeline(u.id).
  Wait for profile and timeline.
  Return ok of Dash with profile set to profile and timeline set to timeline.