anchor.diff:  
   %% NOTE: this is rpc:call-ed by mb_master of 2.0.0
   supported_compat_version() ->
  -    [2, 0].
  +    [3, 0].
   
   %% NOTE: this is rpc:call-ed by mb_master of 2.0.1+
   %%
  
positive.code: mb_master_advertised_version() ->
      [3, 0, 0].
  
  %% TODO: in 3.0 reimplement as compat_version 3.0 to make things
  %% simpler.
  check_is_progress_tracking_supported() ->
      case rpc:multicall(ns_node_disco:nodes_wanted(), cluster_compat_mode, mb_master_advertised_version, [], 30000) of
          {Replies, []} ->
              [R || R <- Replies,
                    R < [2, 0, 2]] =:= [];
          _ ->
              false
      end.
  
  is_enabled_at(undefined = _ClusterVersion, _FeatureVersion) ->
  
negative.code:          check_is_progress_tracking_supported/0,
           get_replication_topology/0,
           is_node_compatible/2,
           split_live_nodes_by_version/1,
           is_cluster_30/0]).
  
  %% NOTE: this is rpc:call-ed by mb_master
  -export([supported_compat_version/0, mb_master_advertised_version/0]).
  