diff --git a/src/jsonrpc/miner_jsonrpc_ledger.erl b/src/jsonrpc/miner_jsonrpc_ledger.erl
index fd9f8f199..08a8fc089 100644
--- a/src/jsonrpc/miner_jsonrpc_ledger.erl
+++ b/src/jsonrpc/miner_jsonrpc_ledger.erl
@@ -10,8 +10,6 @@
 %% jsonrpc_handler
 %%
 
--type json_object() :: #{ binary() => any() }.
-
 handle_rpc(<<"ledger_balance">>, []) ->
     %% get all
     Entries = maps:filter(
@@ -215,12 +213,12 @@ format_ledger_validator(Addr, Val, Ledger, Height) ->
     }.
 
 -spec format_region_parameters([blockchain_region_param_v1:region_param_v1()]) ->
-    [json_object()].
+    [map()].
 format_region_parameters(RegionParameters) ->
     [ format_region_parameter(RegionParameter) || RegionParameter <- RegionParameters ].
 
 -spec format_region_parameter(blockchain_region_param_v1:region_param_v1()) ->
-    json_object().
+    map().
 format_region_parameter(RegionParam) ->
     ChannelFrequencyHz = blockchain_region_param_v1:channel_frequency(RegionParam),
     BandwidthHz = blockchain_region_param_v1:bandwidth(RegionParam),
@@ -235,13 +233,13 @@ format_region_parameter(RegionParam) ->
     }.
 
 -spec format_spreading(blockchain_region_spreading_v1:region_spreading_v1()) ->
-    [json_object()].
+    [map()].
 format_spreading(Spreading) ->
     SpreadingList = blockchain_region_spreading_v1:tagged_spreading(Spreading),
     [ format_spreading_factor(SF) || SF <- SpreadingList ].
 
 -spec format_spreading_factor(blockchain_region_spreading_v1:tagged_spreading()) ->
-    json_object().
+    map().
 format_spreading_factor(SF) ->
     SFAtom = blockchain_region_spreading_v1:region_spreading(SF),
     MaxPacketSize = blockchain_region_spreading_v1:max_packet_size(SF),