diff --git a/src/khepri.erl b/src/khepri.erl
index 3bc706c2..001acf33 100644
--- a/src/khepri.erl
+++ b/src/khepri.erl
@@ -430,8 +430,7 @@
 %%
 %% `undefined' is returned if a tree node has no payload attached to it.
 
--type async_ret() :: khepri_adv:single_result() |
-                     khepri_adv:many_results() |
+-type async_ret() :: khepri_adv:many_results() |
                      khepri_tx:tx_fun_result() |
                      khepri:error({not_leader, ra:server_id()}).
 %% The value returned from of a command function which was executed
@@ -446,11 +445,10 @@
 %% commands which were applied, or `{error, {not_leader, LeaderId}}' if the
 %% commands could not be applied since they were sent to a non-leader member.
 %%
-%% Note that when commands are successfully applied, the return values are in
-%% the {@link khepri_adv} formats - {@link khepri_adv:single_result()} or
-%% {@link khepri_adv:many_results()} - rather than {@link
-%% khepri:minimal_ret()}, even if the command was sent using a function from
-%% the {@link khepri} API such as {@link khepri:put/4}.
+%% Note that when commands are successfully applied, the return values are
+%% {@link khepri_adv:many_results()} rather than {@link khepri:minimal_ret()},
+%% even if the command was sent using a function from the {@link khepri} API
+%% such as {@link khepri:put/4}.
 %%
 %% See {@link khepri:handle_async_ret/2}.
 
@@ -778,10 +776,12 @@ get(PathPattern, Options) when is_map(Options) ->
 
 get(StoreId, PathPattern, Options) ->
     case khepri_adv:get(StoreId, PathPattern, Options) of
-        {ok, #{data := Data}}           -> {ok, Data};
-        {ok, #{sproc := StandaloneFun}} -> {ok, StandaloneFun};
-        {ok, _}                         -> {ok, undefined};
-        Error                           -> Error
+        {ok, NodePropsMap} ->
+            NodeProps = khepri_utils:get_single_node_props(NodePropsMap),
+            Payload = khepri_utils:node_props_to_payload(NodeProps, undefined),
+            {ok, Payload};
+        {error, _} = Error ->
+            Error
     end.
 
 %% -------------------------------------------------------------------
@@ -892,11 +892,14 @@ get_or(PathPattern, Default, Options) when is_map(Options) ->
 
 get_or(StoreId, PathPattern, Default, Options) ->
     case khepri_adv:get(StoreId, PathPattern, Options) of
-        {ok, #{data := Data}}                     -> {ok, Data};
-        {ok, #{sproc := StandaloneFun}}           -> {ok, StandaloneFun};
-        {ok, _}                                   -> {ok, Default};
-        {error, ?khepri_error(node_not_found, _)} -> {ok, Default};
-        Error                                     -> Error
+        {ok, NodePropsMap} ->
+            NodeProps = khepri_utils:get_single_node_props(NodePropsMap),
+            Payload = khepri_utils:node_props_to_payload(NodeProps, Default),
+            {ok, Payload};
+        {error, ?khepri_error(node_not_found, _)} ->
+            {ok, Default};
+        {error, _} = Error ->
+            Error
     end.
 
 %% -------------------------------------------------------------------
@@ -1889,7 +1892,7 @@ filter(StoreId, PathPattern, Pred, Options) when is_function(Pred, 2) ->
     FoldFun = fun(Path, NodeProps, Acc) ->
                       case Pred(Path, NodeProps) of
                           true ->
-                              Payload = node_props_to_payload(
+                              Payload = khepri_utils:node_props_to_payload(
                                           NodeProps, undefined),
                               Acc#{Path => Payload};
                           false ->
@@ -1898,10 +1901,6 @@ filter(StoreId, PathPattern, Pred, Options) when is_function(Pred, 2) ->
               end,
     fold(StoreId, PathPattern, FoldFun, #{}, Options).
 
-node_props_to_payload(#{data := Data}, _Default)           -> Data;
-node_props_to_payload(#{sproc := StandaloneFun}, _Default) -> StandaloneFun;
-node_props_to_payload(_NodeProps, Default)                 -> Default.
-
 %% -------------------------------------------------------------------
 %% run_sproc().
 %% -------------------------------------------------------------------
@@ -1992,14 +1991,18 @@ run_sproc(PathPattern, Args, Options) when is_map(Options) ->
 
 run_sproc(StoreId, PathPattern, Args, Options) ->
     case khepri_adv:get(StoreId, PathPattern, Options) of
-        {ok, #{sproc := StandaloneFun}} ->
-            khepri_sproc:run(StandaloneFun, Args);
-        {ok, NodeProps} ->
-            throw(?khepri_exception(
-                     denied_execution_of_non_sproc_node,
-                     #{path => PathPattern,
-                       args => Args,
-                       node_props => NodeProps}));
+        {ok, NodePropsMap} ->
+            NodeProps = khepri_utils:get_single_node_props(NodePropsMap),
+            case NodeProps of
+                #{sproc := StandaloneFun} ->
+                    khepri_sproc:run(StandaloneFun, Args);
+                _ ->
+                    throw(?khepri_exception(
+                             denied_execution_of_non_sproc_node,
+                             #{path => PathPattern,
+                               args => Args,
+                               node_props => NodeProps}))
+            end;
         {error, Reason} ->
             throw(?khepri_error(
                      failed_to_get_sproc,
diff --git a/src/khepri_adv.erl b/src/khepri_adv.erl
index 0a75e2da..d98d9080 100644
--- a/src/khepri_adv.erl
+++ b/src/khepri_adv.erl
@@ -52,16 +52,10 @@
 %% Structure used to return a map of nodes and their associated properties,
 %% payload and child nodes.
 
--type single_result() :: khepri:ok(khepri:node_props() | #{}) |
-                         khepri:error().
-%% Return value of a query or synchronous command targeting one specific tree
-%% node.
-
 -type many_results() :: khepri_machine:common_ret().
 %% Return value of a query or synchronous command targeting many tree nodes.
 
 -export_type([node_props_map/0,
-              single_result/0,
               many_results/0]).
 
 %% -------------------------------------------------------------------
@@ -70,7 +64,7 @@
 
 -spec get(PathPattern) -> Ret when
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Returns the properties and payload of the tree node pointed to by the
 %% given path pattern.
 %%
@@ -89,11 +83,11 @@ get(PathPattern) ->
 (StoreId, PathPattern) -> Ret when
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result();
+      Ret :: khepri_adv:many_results();
 (PathPattern, Options) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:query_options() | khepri:tree_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Returns the properties and payload of the tree node pointed to by the
 %% given path pattern.
 %%
@@ -118,7 +112,7 @@ get(PathPattern, Options) when is_map(Options) ->
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:query_options() | khepri:tree_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Returns the properties and payload of the tree node pointed to by the
 %% given path pattern.
 %%
@@ -161,15 +155,14 @@ get(PathPattern, Options) when is_map(Options) ->
 %% @param PathPattern the path (or path pattern) to the tree node to get.
 %% @param Options query options.
 %%
-%% @returns an `{ok, NodeProps}' tuple or an `{error, Reason}' tuple.
+%% @returns an `{ok, NodePropsMap}' tuple or an `{error, Reason}' tuple.
 %%
 %% @see get_many/3.
 %% @see khepri:get/3.
 
 get(StoreId, PathPattern, Options) ->
     Options1 = Options#{expect_specific_node => true},
-    Ret = get_many(StoreId, PathPattern, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    get_many(StoreId, PathPattern, Options1).
 
 %% -------------------------------------------------------------------
 %% get_many().
@@ -274,7 +267,7 @@ get_many(StoreId, PathPattern, Options) ->
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
       Ret :: khepri:minimal_ret() |
-             khepri_adv:single_result().
+             khepri_adv:many_results().
 %% @doc Sets the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -294,7 +287,7 @@ put(PathPattern, Data) ->
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
       Ret :: khepri:minimal_ret() |
-             khepri_adv:single_result().
+             khepri_adv:many_results().
 %% @doc Sets the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -314,7 +307,7 @@ put(StoreId, PathPattern, Data) ->
                  khepri:tree_options() |
                  khepri:put_options(),
       Ret :: khepri:minimal_ret() |
-             khepri_adv:single_result() |
+             khepri_adv:many_results() |
              khepri_machine:async_ret().
 %% @doc Sets the payload of the tree node pointed to by the given path
 %% pattern.
@@ -385,8 +378,8 @@ put(StoreId, PathPattern, Data) ->
 %%        khepri_payload:payload()} structure.
 %% @param Options command options.
 %%
-%% @returns in the case of a synchronous call, an `{ok, NodeProps}' tuple or
-%% an `{error, Reason}' tuple; in the case of an asynchronous call, always
+%% @returns in the case of a synchronous call, an `{ok, NodePropsMap}' tuple
+%% or an `{error, Reason}' tuple; in the case of an asynchronous call, always
 %% `ok' (the actual return value may be sent by a message if a correlation ID
 %% was specified).
 %%
@@ -397,8 +390,7 @@ put(StoreId, PathPattern, Data) ->
 
 put(StoreId, PathPattern, Data, Options) ->
     Options1 = Options#{expect_specific_node => true},
-    Ret = put_many(StoreId, PathPattern, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    put_many(StoreId, PathPattern, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% put_many().
@@ -527,7 +519,7 @@ put_many(StoreId, PathPattern, Data, Options) ->
 -spec create(PathPattern, Data) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Creates a tree node with the given payload.
 %%
 %% Calling this function is the same as calling `create(StoreId, PathPattern,
@@ -545,7 +537,7 @@ create(PathPattern, Data) ->
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Creates a tree node with the given payload.
 %%
 %% Calling this function is the same as calling `create(StoreId, PathPattern,
@@ -563,7 +555,7 @@ create(StoreId, PathPattern, Data) ->
       Options :: khepri:command_options() |
                  khepri:tree_options() |
                  khepri:put_options(),
-      Ret :: khepri_adv:single_result() | khepri_machine:async_ret().
+      Ret :: khepri_adv:many_results() | khepri_machine:async_ret().
 %% @doc Creates a tree node with the given payload.
 %%
 %% The behavior is the same as {@link put/4} except that if the tree node
@@ -579,8 +571,8 @@ create(StoreId, PathPattern, Data) ->
 %%        khepri_payload:payload()} structure.
 %% @param Options command options.
 %%
-%% @returns in the case of a synchronous call, an `{ok, NodeProps}' tuple or
-%% an `{error, Reason}' tuple; in the case of an asynchronous call, always
+%% @returns in the case of a synchronous call, an `{ok, NodePropsMap}' tuple
+%% or an `{error, Reason}' tuple; in the case of an asynchronous call, always
 %% `ok' (the actual return value may be sent by a message if a correlation ID
 %% was specified).
 %%
@@ -593,13 +585,7 @@ create(StoreId, PathPattern, Data, Options) ->
     PathPattern2 = khepri_path:combine_with_conditions(
                      PathPattern1, [#if_node_exists{exists = false}]),
     Options1 = Options#{expect_specific_node => true},
-    case do_put(StoreId, PathPattern2, Data, Options1) of
-        {ok, NodePropsMaps} ->
-            [NodeProps] = maps:values(NodePropsMaps),
-            {ok, NodeProps};
-        Error ->
-            Error
-    end.
+    do_put(StoreId, PathPattern2, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% update().
@@ -608,7 +594,7 @@ create(StoreId, PathPattern, Data, Options) ->
 -spec update(PathPattern, Data) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload.
 %%
 %% Calling this function is the same as calling `update(StoreId, PathPattern,
@@ -626,7 +612,7 @@ update(PathPattern, Data) ->
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload.
 %%
 %% Calling this function is the same as calling `update(StoreId, PathPattern,
@@ -644,7 +630,7 @@ update(StoreId, PathPattern, Data) ->
       Options :: khepri:command_options() |
                  khepri:tree_options() |
                  khepri:put_options(),
-      Ret :: khepri_adv:single_result() | khepri_machine:async_ret().
+      Ret :: khepri_adv:many_results() | khepri_machine:async_ret().
 %% @doc Updates an existing tree node with the given payload.
 %%
 %% The behavior is the same as {@link put/4} except that if the tree node
@@ -661,8 +647,8 @@ update(StoreId, PathPattern, Data) ->
 %% @param Extra extra options such as `keep_while' conditions.
 %% @param Options command options.
 %%
-%% @returns in the case of a synchronous call, an `{ok, NodeProps}' tuple or
-%% an `{error, Reason}' tuple; in the case of an asynchronous call, always
+%% @returns in the case of a synchronous call, an `{ok, NodePropsMap}' tuple
+%% or an `{error, Reason}' tuple; in the case of an asynchronous call, always
 %% `ok' (the actual return value may be sent by a message if a correlation ID
 %% was specified).
 %%
@@ -675,8 +661,7 @@ update(StoreId, PathPattern, Data, Options) ->
     PathPattern2 = khepri_path:combine_with_conditions(
                      PathPattern1, [#if_node_exists{exists = true}]),
     Options1 = Options#{expect_specific_node => true},
-    Ret = do_put(StoreId, PathPattern2, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    do_put(StoreId, PathPattern2, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% compare_and_swap().
@@ -686,7 +671,7 @@ update(StoreId, PathPattern, Data, Options) ->
       PathPattern :: khepri_path:pattern(),
       DataPattern :: ets:match_pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload only if its data
 %% matches the given pattern.
 %%
@@ -706,7 +691,7 @@ compare_and_swap(PathPattern, DataPattern, Data) ->
       PathPattern :: khepri_path:pattern(),
       DataPattern :: ets:match_pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload only if its data
 %% matches the given pattern.
 %%
@@ -727,7 +712,7 @@ compare_and_swap(StoreId, PathPattern, DataPattern, Data) ->
       Options :: khepri:command_options() |
                  khepri:tree_options() |
                  khepri:put_options(),
-      Ret :: khepri_adv:single_result() | khepri_machine:async_ret().
+      Ret :: khepri_adv:many_results() | khepri_machine:async_ret().
 %% @doc Updates an existing tree node with the given payload only if its data
 %% matches the given pattern.
 %%
@@ -745,8 +730,8 @@ compare_and_swap(StoreId, PathPattern, DataPattern, Data) ->
 %% @param Extra extra options such as `keep_while' conditions.
 %% @param Options command options.
 %%
-%% @returns in the case of a synchronous call, an `{ok, NodeProps}' tuple or
-%% an `{error, Reason}' tuple; in the case of an asynchronous call, always
+%% @returns in the case of a synchronous call, an `{ok, NodePropsMap}' tuple
+%% or an `{error, Reason}' tuple; in the case of an asynchronous call, always
 %% `ok' (the actual return value may be sent by a message if a correlation ID
 %% was specified).
 %%
@@ -758,8 +743,7 @@ compare_and_swap(StoreId, PathPattern, DataPattern, Data, Options) ->
     PathPattern2 = khepri_path:combine_with_conditions(
                      PathPattern1, [#if_data_matches{pattern = DataPattern}]),
     Options1 = Options#{expect_specific_node => true},
-    Ret = do_put(StoreId, PathPattern2, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    do_put(StoreId, PathPattern2, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% do_put().
@@ -787,7 +771,7 @@ do_put(StoreId, PathPattern, Payload, Options) ->
 
 -spec delete(PathPattern) -> Ret when
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the tree node pointed to by the given path pattern.
 %%
 %% Calling this function is the same as calling `delete(StoreId, PathPattern)'
@@ -805,11 +789,11 @@ delete(PathPattern) ->
 (StoreId, PathPattern) -> Ret when
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result();
+      Ret :: khepri_adv:many_results();
 (PathPattern, Options) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:command_options() | khepri:tree_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the tree node pointed to by the given path pattern.
 %%
 %% This function accepts the following two forms:
@@ -833,7 +817,7 @@ delete(PathPattern, Options) when is_map(Options) ->
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:command_options() | khepri:tree_options(),
-      Ret :: khepri_adv:single_result() | khepri_machine:async_ret().
+      Ret :: khepri_adv:many_results() | khepri_machine:async_ret().
 %% @doc Deletes the tree node pointed to by the given path pattern.
 %%
 %% The `PathPattern' can be provided as a native path pattern (a list of tree
@@ -865,8 +849,8 @@ delete(PathPattern, Options) when is_map(Options) ->
 %% @param PathPattern the path (or path pattern) to the nodes to delete.
 %% @param Options command options such as the command type.
 %%
-%% @returns in the case of a synchronous call, an `{ok, NodeProps}' tuple or
-%% an `{error, Reason}' tuple; in the case of an asynchronous call, always
+%% @returns in the case of a synchronous call, an `{ok, NodePropsMap}' tuple
+%% or an `{error, Reason}' tuple; in the case of an asynchronous call, always
 %% `ok' (the actual return value may be sent by a message if a correlation ID
 %% was specified).
 %%
@@ -876,19 +860,7 @@ delete(PathPattern, Options) when is_map(Options) ->
 delete(StoreId, PathPattern, Options) ->
     %% TODO: Not handled by khepri_machine:delete/3...
     Options1 = Options#{expect_specific_node => true},
-    case khepri_machine:delete(StoreId, PathPattern, Options1) of
-        {ok, NodePropsMap} ->
-            %% It's ok to delete a non-existing tree node. The returned result
-            %% will be an empty map, in which case we return `#{}' as the
-            %% "node properties".
-            NodeProps = case maps:values(NodePropsMap) of
-                            [NP] -> NP;
-                            []   -> #{}
-                        end,
-            {ok, NodeProps};
-        Error ->
-            Error
-    end.
+    khepri_machine:delete(StoreId, PathPattern, Options1).
 
 %% -------------------------------------------------------------------
 %% delete_many().
@@ -988,7 +960,7 @@ delete_many(StoreId, PathPattern, Options) ->
 
 -spec clear_payload(PathPattern) -> Ret when
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -1006,7 +978,7 @@ clear_payload(PathPattern) ->
 -spec clear_payload(StoreId, PathPattern) -> Ret when
       StoreId :: khepri:store_id(),
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -1024,7 +996,7 @@ clear_payload(StoreId, PathPattern) ->
       Options :: khepri:command_options() |
                  khepri:tree_options() |
                  khepri:put_options(),
-      Ret :: khepri_adv:single_result() | khepri_machine:async_ret().
+      Ret :: khepri_adv:many_results() | khepri_machine:async_ret().
 %% @doc Deletes the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -1036,8 +1008,8 @@ clear_payload(StoreId, PathPattern) ->
 %% @param Extra extra options such as `keep_while' conditions.
 %% @param Options command options.
 %%
-%% @returns in the case of a synchronous call, an `{ok, NodeProps}' tuple or
-%% an `{error, Reason}' tuple; in the case of an asynchronous call, always
+%% @returns in the case of a synchronous call, an `{ok, NodePropsMap}' tuple
+%% or an `{error, Reason}' tuple; in the case of an asynchronous call, always
 %% `ok' (the actual return value may be sent by a message if a correlation ID
 %% was specified).
 %%
diff --git a/src/khepri_projection.erl b/src/khepri_projection.erl
index 7a64f0d6..a05def99 100644
--- a/src/khepri_projection.erl
+++ b/src/khepri_projection.erl
@@ -189,7 +189,8 @@ new(Name, ProjectionFun, Options)
         {_CustomFunOptions, _EtsOptions} = Value ->
             Value
     end,
-    EtsOptions1 = maps:fold(fun to_ets_options/3, ?DEFAULT_ETS_OPTS, EtsOptions),
+    EtsOptions1 = maps:fold(
+                    fun to_ets_options/3, ?DEFAULT_ETS_OPTS, EtsOptions),
     ShouldProcessFunction =
     if
         is_function(ProjectionFun, 2) ->
diff --git a/src/khepri_ret.hrl b/src/khepri_ret.hrl
index 84626713..88f6bfd8 100644
--- a/src/khepri_ret.hrl
+++ b/src/khepri_ret.hrl
@@ -6,17 +6,6 @@
 %% refers to Broadcom Inc. and/or its subsidiaries.
 %%
 
--define(common_ret_to_single_result_ret(__Ret),
-        case (__Ret) of
-            {ok, __NodePropsMap} ->
-                [__NodeProps] = maps:values(__NodePropsMap),
-                {ok, __NodeProps};
-            {error, ?khepri_exception(_, _) = __Exception} ->
-                ?khepri_misuse(__Exception);
-            __Error ->
-                __Error
-        end).
-
 -define(result_ret_to_minimal_ret(__Ret),
         case (__Ret) of
             {ok, _} -> ok;
diff --git a/src/khepri_tx.erl b/src/khepri_tx.erl
index 6eda0245..a9a4d83c 100644
--- a/src/khepri_tx.erl
+++ b/src/khepri_tx.erl
@@ -180,10 +180,12 @@ get(PathPattern) ->
 
 get(PathPattern, Options) ->
     case khepri_tx_adv:get(PathPattern, Options) of
-        {ok, #{data := Data}}           -> {ok, Data};
-        {ok, #{sproc := StandaloneFun}} -> {ok, StandaloneFun};
-        {ok, _}                         -> {ok, undefined};
-        Error                           -> Error
+        {ok, NodePropsMap} ->
+            NodeProps = khepri_utils:get_single_node_props(NodePropsMap),
+            Payload = khepri_utils:node_props_to_payload(NodeProps, undefined),
+            {ok, Payload};
+        {error, _} = Error ->
+            Error
     end.
 
 %% -------------------------------------------------------------------
@@ -220,11 +222,14 @@ get_or(PathPattern, Default) ->
 
 get_or(PathPattern, Default, Options) ->
     case khepri_tx_adv:get(PathPattern, Options) of
-        {ok, #{data := Data}}                     -> {ok, Data};
-        {ok, #{sproc := StandaloneFun}}           -> {ok, StandaloneFun};
-        {ok, _}                                   -> {ok, Default};
-        {error, ?khepri_error(node_not_found, _)} -> {ok, Default};
-        Error                                     -> Error
+        {ok, NodePropsMap} ->
+            NodeProps = khepri_utils:get_single_node_props(NodePropsMap),
+            Payload = khepri_utils:node_props_to_payload(NodeProps, Default),
+            {ok, Payload};
+        {error, ?khepri_error(node_not_found, _)} ->
+            {ok, Default};
+        {error, _} = Error ->
+            Error
     end.
 
 %% -------------------------------------------------------------------
diff --git a/src/khepri_tx_adv.erl b/src/khepri_tx_adv.erl
index 0f3fc9dd..5ab4efa0 100644
--- a/src/khepri_tx_adv.erl
+++ b/src/khepri_tx_adv.erl
@@ -64,7 +64,7 @@
 
 -spec get(PathPattern) -> Ret when
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Returns the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -79,7 +79,7 @@ get(PathPattern) ->
 -spec get(PathPattern, Options) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:tree_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Returns the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -90,8 +90,7 @@ get(PathPattern) ->
 
 get(PathPattern, Options) ->
     Options1 = Options#{expect_specific_node => true},
-    Ret = get_many(PathPattern, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    get_many(PathPattern, Options1).
 
 %% -------------------------------------------------------------------
 %% get_many().
@@ -148,7 +147,7 @@ do_get_many(PathPattern, Fun, Acc, Options) ->
 -spec put(PathPattern, Data) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Sets the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -164,7 +163,7 @@ put(PathPattern, Data) ->
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
       Options :: khepri:tree_options() | khepri:put_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Sets the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -175,8 +174,7 @@ put(PathPattern, Data) ->
 
 put(PathPattern, Data, Options) ->
     Options1 = Options#{expect_specific_node => true},
-    Ret = put_many(PathPattern, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    put_many(PathPattern, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% put_many().
@@ -231,7 +229,7 @@ put_many(PathPattern, Data, Options) ->
 -spec create(PathPattern, Data) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Creates a tree node with the given payload.
 %%
 %% This is the same as {@link khepri_adv:create/3} but inside the context of a
@@ -246,7 +244,7 @@ create(PathPattern, Data) ->
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
       Options :: khepri:tree_options() | khepri:put_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Creates a tree node with the given payload.
 %%
 %% This is the same as {@link khepri_adv:create/4} but inside the context of a
@@ -259,8 +257,7 @@ create(PathPattern, Data, Options) ->
     PathPattern2 = khepri_path:combine_with_conditions(
                      PathPattern1, [#if_node_exists{exists = false}]),
     Options1 = Options#{expect_specific_node => true},
-    Ret = put_many(PathPattern2, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    put_many(PathPattern2, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% update().
@@ -269,7 +266,7 @@ create(PathPattern, Data, Options) ->
 -spec update(PathPattern, Data) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload.
 %%
 %% This is the same as {@link khepri_adv:update/3} but inside the context of a
@@ -284,7 +281,7 @@ update(PathPattern, Data) ->
       PathPattern :: khepri_path:pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
       Options :: khepri:tree_options() | khepri:put_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload.
 %%
 %% This is the same as {@link khepri_adv:update/4} but inside the context of a
@@ -297,8 +294,7 @@ update(PathPattern, Data, Options) ->
     PathPattern2 = khepri_path:combine_with_conditions(
                      PathPattern1, [#if_node_exists{exists = true}]),
     Options1 = Options#{expect_specific_node => true},
-    Ret = put_many(PathPattern2, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    put_many(PathPattern2, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% compare_and_swap().
@@ -308,7 +304,7 @@ update(PathPattern, Data, Options) ->
       PathPattern :: khepri_path:pattern(),
       DataPattern :: ets:match_pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload only if its data
 %% matches the given pattern.
 %%
@@ -326,7 +322,7 @@ compare_and_swap(PathPattern, DataPattern, Data) ->
       DataPattern :: ets:match_pattern(),
       Data :: khepri_payload:payload() | khepri:data() | fun(),
       Options :: khepri:tree_options() | khepri:put_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Updates an existing tree node with the given payload only if its data
 %% matches the given pattern.
 %%
@@ -340,8 +336,7 @@ compare_and_swap(PathPattern, DataPattern, Data, Options) ->
     PathPattern2 = khepri_path:combine_with_conditions(
                      PathPattern1, [#if_data_matches{pattern = DataPattern}]),
     Options1 = Options#{expect_specific_node => true},
-    Ret = put_many(PathPattern2, Data, Options1),
-    ?common_ret_to_single_result_ret(Ret).
+    put_many(PathPattern2, Data, Options1).
 
 %% -------------------------------------------------------------------
 %% delete().
@@ -349,7 +344,7 @@ compare_and_swap(PathPattern, DataPattern, Data, Options) ->
 
 -spec delete(PathPattern) -> Ret when
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the tree node pointed to by the given path pattern.
 %%
 %% This is the same as {@link khepri_adv:delete/2} but inside the context of a
@@ -363,7 +358,7 @@ delete(PathPattern) ->
 -spec delete(PathPattern, Options) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:tree_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the tree node pointed to by the given path pattern.
 %%
 %% This is the same as {@link khepri_adv:delete/3} but inside the context of a
@@ -373,19 +368,7 @@ delete(PathPattern) ->
 
 delete(PathPattern, Options) ->
     Options1 = Options#{expect_specific_node => true},
-    case delete_many(PathPattern, Options1) of
-        {ok, NodePropsMap} ->
-            %% It's ok to delete a non-existing tree node. The returned result
-            %% will be an empty map, in which case we return `#{}' as the
-            %% "node properties".
-            NodeProps = case maps:values(NodePropsMap) of
-                            [NP] -> NP;
-                            []   -> #{}
-                        end,
-            {ok, NodeProps};
-        Error ->
-            Error
-    end.
+    delete_many(PathPattern, Options1).
 
 %% -------------------------------------------------------------------
 %% delete_many().
@@ -434,7 +417,7 @@ delete_many(PathPattern, Options) ->
 
 -spec clear_payload(PathPattern) -> Ret when
       PathPattern :: khepri_path:pattern(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the payload of the tree node pointed to by the given path
 %% pattern.
 %%
@@ -449,7 +432,7 @@ clear_payload(PathPattern) ->
 -spec clear_payload(PathPattern, Options) -> Ret when
       PathPattern :: khepri_path:pattern(),
       Options :: khepri:tree_options() | khepri:put_options(),
-      Ret :: khepri_adv:single_result().
+      Ret :: khepri_adv:many_results().
 %% @doc Deletes the payload of the tree node pointed to by the given path
 %% pattern.
 %%
diff --git a/src/khepri_utils.erl b/src/khepri_utils.erl
index fb0f978d..511b2a7c 100644
--- a/src/khepri_utils.erl
+++ b/src/khepri_utils.erl
@@ -20,6 +20,7 @@
          sleep/2,
          is_ra_server_alive/1,
 
+         get_single_node_props/1,
          node_props_to_payload/2,
 
          flat_struct_to_tree/1,
@@ -90,6 +91,10 @@ sleep(Time, Timeout) when Time > Timeout ->
 is_ra_server_alive({RegName, Node}) when Node =:= node() ->
     is_pid(erlang:whereis(RegName)).
 
+get_single_node_props(NodePropsMap) ->
+    [NodeProps] = maps:values(NodePropsMap),
+    NodeProps.
+
 node_props_to_payload(#{data := Data}, _Default)           -> Data;
 node_props_to_payload(#{sproc := StandaloneFun}, _Default) -> StandaloneFun;
 node_props_to_payload(_NodeProps, Default)                 -> Default.
diff --git a/test/advanced_delete.erl b/test/advanced_delete.erl
index 22208306..76d187e2 100644
--- a/test/advanced_delete.erl
+++ b/test/advanced_delete.erl
@@ -32,11 +32,11 @@ delete_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:delete(?FUNCTION_NAME, [foo])),
       ?_assertEqual(
          {error, ?khepri_error(node_not_found, #{node_name => foo,
@@ -73,7 +73,7 @@ delete_many_on_existing_node_with_condition_true_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
          {ok, #{[foo] => #{data => foo_value,
@@ -91,15 +91,15 @@ delete_many_on_existing_node_with_condition_false_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
          {ok, #{}},
          khepri_adv:delete_many(
            ?FUNCTION_NAME, [#if_name_matches{regex = "bar"}])),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_payload_from_non_existing_node_test_() ->
@@ -120,14 +120,14 @@ clear_payload_from_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 2}}},
          khepri_adv:clear_payload(?FUNCTION_NAME, [foo])),
       ?_assertEqual(
-         {ok, #{payload_version => 2}},
+         {ok, #{[foo] => #{payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_payload_with_keep_while_test_() ->
@@ -135,15 +135,15 @@ clear_payload_with_keep_while_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 2}}},
          khepri_adv:clear_payload(
            ?FUNCTION_NAME, [foo], #{keep_while => #{}})),
       ?_assertEqual(
-         {ok, #{payload_version => 2}},
+         {ok, #{[foo] => #{payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_payload_with_options_test_() ->
@@ -151,14 +151,14 @@ clear_payload_with_options_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 2}}},
          khepri_adv:clear_payload(?FUNCTION_NAME, [foo], #{async => false})),
       ?_assertEqual(
-         {ok, #{payload_version => 2}},
+         {ok, #{[foo] => #{payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_many_payloads_from_non_existing_node_test_() ->
@@ -179,10 +179,10 @@ clear_many_payloads_from_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo1] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo1], foo1_value)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo2, bar] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo2, bar], bar_value)),
       ?_assertEqual(
          {ok, #{[foo1] => #{data => foo1_value,
diff --git a/test/advanced_get.erl b/test/advanced_get.erl
index 5c97fd70..77e89a3e 100644
--- a/test/advanced_get.erl
+++ b/test/advanced_get.erl
@@ -31,11 +31,11 @@ get_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 get_existing_node_with_sproc_test_() ->
@@ -43,11 +43,12 @@ get_existing_node_with_sproc_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], fun() -> ok end)),
       ?_assertMatch(
-         {ok, #{sproc := Fun,
-                payload_version := 1}} when ?IS_HORUS_STANDALONE_FUN(Fun),
+         {ok, #{[foo] := #{sproc := Fun,
+                           payload_version := 1}}}
+           when ?IS_HORUS_STANDALONE_FUN(Fun),
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 get_existing_node_with_no_payload_test_() ->
@@ -55,10 +56,10 @@ get_existing_node_with_no_payload_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo, bar] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo, bar], bar_value)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_get_call_test_() ->
@@ -84,10 +85,10 @@ get_many_existing_nodes_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo, bar] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo, bar], bar_value)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[baz] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [baz], baz_value)),
       ?_assertEqual(
          {ok, #{[foo] => #{payload_version => 1},
diff --git a/test/advanced_put.erl b/test/advanced_put.erl
index b9f3d4ad..f251c09a 100644
--- a/test/advanced_put.erl
+++ b/test/advanced_put.erl
@@ -20,11 +20,11 @@ create_non_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 create_existing_node_test_() ->
@@ -32,7 +32,7 @@ create_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
          {error,
@@ -73,11 +73,11 @@ insert_non_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:put(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 insert_existing_node_test_() ->
@@ -85,19 +85,19 @@ insert_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
-         {ok, #{data => foo_value1,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value1,
+                           payload_version => 2}}},
          khepri_adv:put(?FUNCTION_NAME, [foo], foo_value2)),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:put(?FUNCTION_NAME, [foo], foo_value2, #{})),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_put_call_test_() ->
@@ -115,10 +115,10 @@ insert_many_non_existing_nodes_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[a] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [a], ?NO_PAYLOAD)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[b] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [b], ?NO_PAYLOAD)),
       ?_assertEqual(
          {ok, #{[a, foo] => #{payload_version => 1},
@@ -138,10 +138,10 @@ insert_many_existing_nodes_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[a, foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [a, foo], foo_value_a)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[b, foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [b, foo], foo_value_b)),
       ?_assertEqual(
          {ok, #{[a, foo] => #{data => foo_value_a,
@@ -196,15 +196,15 @@ update_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
-         {ok, #{data => foo_value1,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value1,
+                           payload_version => 2}}},
          khepri_adv:update(?FUNCTION_NAME, [foo], foo_value2)),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_update_call_test_() ->
@@ -240,16 +240,16 @@ compare_and_swap_matching_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
-         {ok, #{data => foo_value1,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value1,
+                           payload_version => 2}}},
          khepri_adv:compare_and_swap(
            ?FUNCTION_NAME, [foo], foo_value1, foo_value2)),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 compare_and_swap_mismatching_node_test_() ->
@@ -257,7 +257,7 @@ compare_and_swap_mismatching_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertMatch(
          {error,
@@ -277,17 +277,17 @@ compare_and_swap_with_options_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
-         {ok, #{data => foo_value1,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value1,
+                           payload_version => 2}}},
          khepri_adv:compare_and_swap(
            ?FUNCTION_NAME, [foo], foo_value1, foo_value2,
            #{async => false})),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_compare_and_swap_call_test_() ->
diff --git a/test/advanced_tx_delete.erl b/test/advanced_tx_delete.erl
index 3c87f464..483c4bbe 100644
--- a/test/advanced_tx_delete.erl
+++ b/test/advanced_tx_delete.erl
@@ -37,7 +37,7 @@ delete_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -49,8 +49,8 @@ delete_existing_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value,
-                 payload_version => 1}}},
+          {ok, #{[foo] => #{data => foo_value,
+                            payload_version => 1}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:delete([foo])
@@ -102,7 +102,7 @@ delete_many_on_existing_node_with_condition_true_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -135,7 +135,7 @@ delete_many_on_existing_node_with_condition_false_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
          {ok, {ok, #{}}},
@@ -147,8 +147,8 @@ delete_many_on_existing_node_with_condition_false_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_payload_from_non_existing_node_test_() ->
@@ -174,7 +174,7 @@ clear_payload_from_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -186,8 +186,8 @@ clear_payload_from_existing_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:clear_payload([foo])
@@ -195,7 +195,7 @@ clear_payload_from_existing_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{payload_version => 2}},
+         {ok, #{[foo] => #{payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_payload_with_keep_while_test_() ->
@@ -203,12 +203,12 @@ clear_payload_with_keep_while_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:clear_payload(
@@ -217,7 +217,7 @@ clear_payload_with_keep_while_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{payload_version => 2}},
+         {ok, #{[foo] => #{payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_payload_with_options_test_() ->
@@ -225,12 +225,12 @@ clear_payload_with_options_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:clear_payload(
@@ -239,7 +239,7 @@ clear_payload_with_options_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{payload_version => 2}},
+         {ok, #{[foo] => #{payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 clear_many_payloads_from_non_existing_node_test_() ->
@@ -265,10 +265,10 @@ clear_many_payloads_from_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo1] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo1], foo1_value)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo2, bar] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo2, bar], bar_value)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
diff --git a/test/advanced_tx_get.erl b/test/advanced_tx_get.erl
index a10e9dd3..539c6d61 100644
--- a/test/advanced_tx_get.erl
+++ b/test/advanced_tx_get.erl
@@ -37,12 +37,12 @@ get_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value)),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value,
-                 payload_version => 1}}},
+          {ok, #{[foo] => #{data => foo_value,
+                            payload_version => 1}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:get([foo])
@@ -51,8 +51,8 @@ get_existing_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value,
-                 payload_version => 1}}},
+          {ok, #{[foo] => #{data => foo_value,
+                            payload_version => 1}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:get([foo])
@@ -68,8 +68,8 @@ get_existing_node_with_sproc_test_() ->
          ok,
          khepri:create(?FUNCTION_NAME, [foo], fun() -> ok end)),
       ?_assertMatch(
-         {ok, {ok, #{sproc := StoredFun,
-                     payload_version := 1}}}
+         {ok, {ok, #{[foo] := #{sproc := StoredFun,
+                                payload_version := 1}}}}
            when ?IS_HORUS_STANDALONE_FUN(StoredFun),
          begin
              Fun = fun() ->
@@ -83,11 +83,11 @@ get_existing_node_with_no_payload_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo, bar] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo, bar], bar_value)),
       ?_assertEqual(
          {ok,
-          {ok, #{payload_version => 1}}},
+          {ok, #{[foo] => #{payload_version => 1}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:get([foo])
@@ -128,10 +128,10 @@ get_many_existing_nodes_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo, bar] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo, bar], bar_value)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[baz] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [baz], baz_value)),
       ?_assertEqual(
          {ok,
diff --git a/test/advanced_tx_put.erl b/test/advanced_tx_put.erl
index 9ccce28e..3b61217d 100644
--- a/test/advanced_tx_put.erl
+++ b/test/advanced_tx_put.erl
@@ -28,7 +28,7 @@ create_non_existing_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, ro)
          end),
       ?_assertEqual(
-         {ok, {ok, #{payload_version => 1}}},
+         {ok, {ok, #{[foo] => #{payload_version => 1}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:create([foo], foo_value)
@@ -36,8 +36,8 @@ create_non_existing_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 create_existing_node_test_() ->
@@ -45,7 +45,7 @@ create_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
          {ok,
@@ -103,7 +103,7 @@ insert_non_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, {ok, #{payload_version => 1}}},
+         {ok, {ok, #{[foo] => #{payload_version => 1}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:put([foo], foo_value)
@@ -111,8 +111,8 @@ insert_non_existing_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value,
-                payload_version => 1}},
+         {ok, #{[foo] => #{data => foo_value,
+                           payload_version => 1}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 insert_existing_node_test_() ->
@@ -120,7 +120,7 @@ insert_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -132,8 +132,8 @@ insert_existing_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value1,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value1,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:put([foo], foo_value2)
@@ -142,8 +142,8 @@ insert_existing_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value2,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value2,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:put([foo], foo_value2, #{})
@@ -151,8 +151,8 @@ insert_existing_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_put_call_test_() ->
@@ -176,10 +176,10 @@ insert_many_non_existing_nodes_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[a] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [a], ?NO_PAYLOAD)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[b] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [b], ?NO_PAYLOAD)),
       ?_assertEqual(
          {ok,
@@ -204,10 +204,10 @@ insert_many_existing_nodes_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[a, foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [a, foo], foo_value_a)),
       ?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[b, foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [b, foo], foo_value_b)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -295,7 +295,7 @@ update_existing_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -307,8 +307,8 @@ update_existing_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value1,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value1,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:update([foo], foo_value2)
@@ -316,8 +316,8 @@ update_existing_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_update_call_test_() ->
@@ -364,7 +364,7 @@ compare_and_swap_matching_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertError(
          ?khepri_exception(denied_update_in_readonly_tx, #{}),
@@ -377,8 +377,8 @@ compare_and_swap_matching_node_test_() ->
          end),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value1,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value1,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:compare_and_swap(
@@ -387,8 +387,8 @@ compare_and_swap_matching_node_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 compare_and_swap_mismatching_node_test_() ->
@@ -396,7 +396,7 @@ compare_and_swap_mismatching_node_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertMatch(
          {ok,
@@ -422,12 +422,12 @@ compare_and_swap_with_options_test_() ->
      fun() -> test_ra_server_helpers:setup(?FUNCTION_NAME) end,
      fun(Priv) -> test_ra_server_helpers:cleanup(Priv) end,
      [?_assertEqual(
-         {ok, #{payload_version => 1}},
+         {ok, #{[foo] => #{payload_version => 1}}},
          khepri_adv:create(?FUNCTION_NAME, [foo], foo_value1)),
       ?_assertEqual(
          {ok,
-          {ok, #{data => foo_value1,
-                 payload_version => 2}}},
+          {ok, #{[foo] => #{data => foo_value1,
+                            payload_version => 2}}}},
          begin
              Fun = fun() ->
                            khepri_tx_adv:compare_and_swap(
@@ -437,8 +437,8 @@ compare_and_swap_with_options_test_() ->
              khepri:transaction(?FUNCTION_NAME, Fun, rw)
          end),
       ?_assertEqual(
-         {ok, #{data => foo_value2,
-                payload_version => 2}},
+         {ok, #{[foo] => #{data => foo_value2,
+                           payload_version => 2}}},
          khepri_adv:get(?FUNCTION_NAME, [foo]))]}.
 
 invalid_compare_and_swap_call_test_() ->
diff --git a/test/async_option.erl b/test/async_option.erl
index e7d12ccf..3264fc96 100644
--- a/test/async_option.erl
+++ b/test/async_option.erl
@@ -25,7 +25,7 @@ async_unset_in_put_test_() ->
                 ok,
                 khepri:put(?FUNCTION_NAME, [foo], ?NO_PAYLOAD)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -41,7 +41,7 @@ async_false_in_put_test_() ->
                 khepri:put(
                   ?FUNCTION_NAME, [foo], ?NO_PAYLOAD, #{async => false})),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -66,7 +66,7 @@ async_true_in_put_test_() ->
                    end,
                    khepri:exists(?FUNCTION_NAME, [foo]), lists:seq(1, 60)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -88,7 +88,7 @@ async_with_correlation_in_put_test_() ->
                [{Correlation, {ok, #{[foo] => #{}}}}],
                khepri:handle_async_ret(?FUNCTION_NAME, RaEvent)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -113,7 +113,7 @@ async_with_priority_in_put_test_() ->
                    end,
                    khepri:exists(?FUNCTION_NAME, [foo]), lists:seq(1, 60)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -135,7 +135,7 @@ async_with_correlation_and_priority_in_put_test_() ->
                [{Correlation, {ok, #{[foo] => #{}}}}],
                khepri:handle_async_ret(?FUNCTION_NAME, RaEvent)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -311,7 +311,7 @@ async_unset_in_transaction_test_() ->
                 {ok, ok},
                 khepri:transaction(?FUNCTION_NAME, Fun)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -328,7 +328,7 @@ async_false_in_transaction_test_() ->
                 khepri:transaction(
                   ?FUNCTION_NAME, Fun, #{async => false})),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -354,7 +354,7 @@ async_true_in_transaction_test_() ->
                    end,
                    khepri:exists(?FUNCTION_NAME, [foo]), lists:seq(1, 60)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -376,7 +376,7 @@ async_with_correlation_in_transaction_test_() ->
                [{Correlation, ok}],
                khepri:handle_async_ret(?FUNCTION_NAME, RaEvent)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -432,7 +432,7 @@ async_with_priority_in_transaction_test_() ->
                    end,
                    khepri:exists(?FUNCTION_NAME, [foo]), lists:seq(1, 60)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
@@ -455,7 +455,7 @@ async_with_correlation_and_priority_in_transaction_test_() ->
                [{Correlation, ok}],
                khepri:handle_async_ret(?FUNCTION_NAME, RaEvent)),
              ?assertEqual(
-                {ok, #{payload_version => 1}},
+                {ok, #{[foo] => #{payload_version => 1}}},
                 khepri_adv:get(?FUNCTION_NAME, [foo]))
          end)
      ]}.
diff --git a/test/cluster_SUITE.erl b/test/cluster_SUITE.erl
index a38cde37..0a413569 100644
--- a/test/cluster_SUITE.erl
+++ b/test/cluster_SUITE.erl
@@ -1522,20 +1522,20 @@ can_use_default_store_on_single_node(_Config) ->
        {error, ?khepri_error(mismatching_node, _)},
         khepri_adv:create([foo], value1)),
     ?assertEqual(
-       {ok, #{data => value4,
-              payload_version => 5}},
+       {ok, #{[foo] => #{data => value4,
+                         payload_version => 5}}},
        khepri_adv:put([foo], value2)),
     ?assertEqual(
        {ok, #{[foo] => #{data => value2,
                          payload_version => 5}}},
        khepri_adv:put_many([foo], value2)),
     ?assertEqual(
-       {ok, #{data => value2,
-              payload_version => 6}},
+       {ok, #{[foo] => #{data => value2,
+                         payload_version => 6}}},
        khepri_adv:update([foo], value3)),
     ?assertEqual(
-       {ok, #{data => value3,
-              payload_version => 7}},
+       {ok, #{[foo] => #{data => value3,
+                         payload_version => 7}}},
        khepri_adv:compare_and_swap([foo], value3, value4)),
 
     ?assertEqual(true, khepri:exists([foo])),
@@ -1579,12 +1579,12 @@ can_use_default_store_on_single_node(_Config) ->
        khepri:filter([foo], fun(_P, _NP) -> true end, #{})),
 
     ?assertEqual(
-       {ok, #{data => value4,
-              payload_version => 7}},
+       {ok, #{[foo] => #{data => value4,
+                         payload_version => 7}}},
        khepri_adv:get([foo])),
     ?assertEqual(
-       {ok, #{data => value4,
-              payload_version => 7}},
+       {ok, #{[foo] => #{data => value4,
+                         payload_version => 7}}},
        khepri_adv:get([foo], #{})),
     ?assertEqual(
        {ok, #{[foo] => #{data => value4,
@@ -1641,7 +1641,9 @@ can_use_default_store_on_single_node(_Config) ->
     ?assertEqual(
        false,
        khepri:has_projection(ProjectionName1, #{favor => consistency})),
-    Projection1 = khepri_projection:new(ProjectionName1, copy),
+    Projection1 = khepri_projection:new(
+                    ProjectionName1,
+                    fun(Path, Data) -> {Path, Data} end),
     ?assertEqual(ok, khepri:register_projection("/**", Projection1)),
     ?assertEqual(
        {error, ?khepri_error(
@@ -1655,7 +1657,8 @@ can_use_default_store_on_single_node(_Config) ->
     ProjectionName2 = projection2,
     ?assertEqual(false, khepri:has_projection(ProjectionName2)),
     Projection2 = khepri_projection:new(
-                    ProjectionName2, copy,
+                    ProjectionName2,
+                    fun(Path, Data) -> {Data, Path} end,
                     #{read_concurrency => true, keypos => 2}),
     ?assertEqual(ok, khepri:register_projection("/**", Projection2, #{})),
     ?assertEqual(true, khepri:has_projection(ProjectionName2)),
@@ -1683,14 +1686,14 @@ can_use_default_store_on_single_node(_Config) ->
 
     ?assertEqual(ok, khepri:create([bar], value1)),
     ?assertEqual(
-       {ok, #{data => value1,
-              payload_version => 2}},
+       {ok, #{[bar] => #{data => value1,
+                         payload_version => 2}}},
        khepri_adv:clear_payload([bar])),
     ?assertEqual(
        {ok, #{[bar] => #{payload_version => 2}}},
        khepri_adv:clear_many_payloads([bar])),
     ?assertEqual(
-       {ok, #{payload_version => 2}},
+       {ok, #{[bar] => #{payload_version => 2}}},
        khepri_adv:delete([bar])),
     ?assertMatch(
        {ok, #{}},