    def terminate(_, State[]) do
    end
 
-   @nil_value MsgPack.pack(nil)
-
    @spec lookup_cell(Genomu.cell, State.t) :: term | nil
    defp lookup_cell({key, nil}, State[tab: tab]) do
      case ETS.lookup(tab, key) do

     {value, rev} = lookup_cell(cell, state)
     case cmd do
       {cmd_name, operation} when cmd_name in [:apply, :set] ->
         new_value = Genomu.Operation.apply(operation, value)
         serialized = Genomu.Operation.serialize(operation)
         stage({key, new_rev}, serialized, new_value, state)
       {:get = cmd_name, operation} ->
         new_value = Genomu.Operation.apply(operation, value)
     end
     case cmd_name do
       :apply ->

   @type command :: {Genomu.cell, Genomu.revision, Genomu.command,
                     Genomu.Coordinator.ref}
   @type commit :: {:C, ITC.t, binary, [Genomu.Transaction.entry], Genomu.Coordinator.ref}

   @nil_value MsgPack.pack(nil)

   require Lager

