code: func (s *Storage) Tail(c context.Context, project types.ProjectName, path types.StreamPath) (*storage.Entry, error) {
  	var r *rec
  
  	// Find the latest log, then return it.
  	err := s.run(func() error {
  		ls := s.getLogStreamLocked(project, path, false)
  		if ls == nil {
  			return storage.ErrDoesNotExist
  		}
  
  		r = &rec{
  			index: ls.latestIndex,
  			data:  ls.logs[ls.latestIndex],
  		}
  		return nil
  	})
  	if err != nil {
  		return nil, err
  	}
  	return storage.MakeEntry(r.data, r.index), nil
  }
docs: // Tail implements storage.Storage.