diff --git a/src/lua/asobi_lua_api.erl b/src/lua/asobi_lua_api.erl
index 975f162..7f321b5 100644
--- a/src/lua/asobi_lua_api.erl
+++ b/src/lua/asobi_lua_api.erl
@@ -65,6 +65,7 @@ game.terrain.preload(coords_list)                -- preload chunks async
 
 -export([install/2]).
 -export([deep_decode/1, decode_to_map/2]).
+-export([to_storage_value/1]).
 
 -spec install(map(), dynamic()) -> dynamic().
 install(Ctx, St0) ->
@@ -354,7 +355,7 @@ fun_storage_set() ->
     fun(Args, St) ->
         case decode_args(Args, St) of
             [Collection, Key, Value] when is_binary(Collection), is_binary(Key) ->
-                wrap_result(storage_set(Collection, Key, undefined, to_map(Value)), St);
+                wrap_result(storage_set(Collection, Key, undefined, to_storage_value(Value)), St);
             _ ->
                 error_result(~"set requires (collection, key, value)", St)
         end
@@ -378,7 +379,7 @@ fun_storage_player_set() ->
             [PlayerId, Collection, Key, Value] when
                 is_binary(PlayerId), is_binary(Collection), is_binary(Key)
             ->
-                wrap_result(storage_set(Collection, Key, PlayerId, to_map(Value)), St);
+                wrap_result(storage_set(Collection, Key, PlayerId, to_storage_value(Value)), St);
             _ ->
                 error_result(~"player_set requires (player_id, collection, key, value)", St)
         end
@@ -612,7 +613,8 @@ fun_terrain_preload(_) ->
 
 %% --- Storage helpers ---
 
--spec storage_get(binary(), binary(), binary() | undefined) -> {ok, map()} | {error, term()}.
+-spec storage_get(binary(), binary(), binary() | undefined) ->
+    {ok, term()} | {error, term()}.
 storage_get(Collection, Key, PlayerId) ->
     Q0 = kura_query:from(asobi_storage),
     Q1 = kura_query:where(Q0, {collection, Collection}),
@@ -624,7 +626,8 @@ storage_get(Collection, Key, PlayerId) ->
         {error, _} = Err -> Err
     end.
 
--spec storage_set(binary(), binary(), binary() | undefined, map()) -> {ok, map()} | {error, term()}.
+-spec storage_set(binary(), binary(), binary() | undefined, term()) ->
+    {ok, term()} | {error, term()}.
 storage_set(Collection, Key, PlayerId, Value) ->
     case storage_get(Collection, Key, PlayerId) of
         {ok, _} ->
@@ -785,6 +788,45 @@ to_map_acc([{K, V} | T], Acc) when is_binary(K) ->
 to_map_acc([_ | T], Acc) ->
     to_map_acc(T, Acc).
 
+%% Coerce a Luerl-decoded value into a shape `asobi_storage`'s jsonb column
+%% can round-trip. Unlike `to_map/1` (which silently drops anything that
+%% isn't a map or string-keyed proplist), this preserves the JSON-compatible
+%% leaf types — numbers, binaries, booleans, nil, and array-shaped tables.
+%% Game scripts can therefore use plain scalars as storage values:
+%%
+%%   game.storage.player_set(pid, "barrow", "run_loot", 5)
+%%
+%% rather than having to wrap them as `{ n = 5 }` to avoid silent data loss.
+%% Maps and nested tables recurse so e.g. `{ position = { x = 1, y = 2 } }`
+%% round-trips intact.
+-spec to_storage_value(term()) -> term().
+to_storage_value(V) when is_number(V); is_boolean(V); is_binary(V) -> V;
+to_storage_value(nil) ->
+    nil;
+to_storage_value(V) when is_map(V) ->
+    maps:map(fun(_K, Val) -> to_storage_value(Val) end, V);
+to_storage_value([{K, _} | _] = L) when is_binary(K) ->
+    %% String-keyed proplist — Luerl's representation of `{ k = v }`.
+    maps:from_list([{Key, to_storage_value(Val)} || {Key, Val} <- L]);
+to_storage_value([]) ->
+    %% Empty Lua tables are ambiguous (could be either array or map). Round
+    %% to an empty map for parity with `to_map/1`'s prior behaviour. This
+    %% clause must come before the generic `is_list/1` clause below.
+    #{};
+to_storage_value([{K, _} | _] = L) when is_integer(K) ->
+    %% Integer-keyed proplist — Luerl's representation of `{ a, b, c }`
+    %% when handed an undecoded table.
+    [to_storage_value(Val) || {_N, Val} <- lists:sort(L)];
+to_storage_value(L) when is_list(L) ->
+    %% Plain list — `deep_decode/1` already flattens an integer-keyed
+    %% proplist into this shape, so callers passing a deep-decoded
+    %% value land here for Lua arrays.
+    [to_storage_value(V) || V <- L];
+to_storage_value(_) ->
+    %% Unsupported (Luerl function refs etc.) — surface as `nil` rather
+    %% than silently masking with an empty map.
+    nil.
+
 -spec ensure_pairs([term()]) -> [{term(), term()}].
 ensure_pairs(L) ->
     [{K, V} || {K, V} <- L].
diff --git a/test/asobi_lua_api_tests.erl b/test/asobi_lua_api_tests.erl
index 7ae7d8e..cd13147 100644
--- a/test/asobi_lua_api_tests.erl
+++ b/test/asobi_lua_api_tests.erl
@@ -53,7 +53,14 @@ api_test_() ->
         {"game.spatial.query_rect errors without zone", fun spatial_query_rect_no_zone/0},
         {"game.terrain.get_chunk returns data", fun terrain_get_chunk/0},
         {"game.terrain.get_chunk errors without store", fun terrain_get_chunk_no_store/0},
-        {"game.terrain.preload forwards coords", fun terrain_preload/0}
+        {"game.terrain.preload forwards coords", fun terrain_preload/0},
+        {"to_storage_value preserves scalars", fun to_storage_value_scalars/0},
+        {"to_storage_value preserves maps", fun to_storage_value_maps/0},
+        {"to_storage_value preserves arrays", fun to_storage_value_arrays/0},
+        {"to_storage_value preserves nested structures", fun to_storage_value_nested/0},
+        {"player_set forwards a scalar number", fun storage_player_set_scalar/0},
+        {"player_set forwards a binary", fun storage_player_set_binary/0},
+        {"player_set forwards an array", fun storage_player_set_array/0}
     ]}.
 
 setup() ->
@@ -405,6 +412,88 @@ terrain_preload() ->
     {ok, [true | _], _} = eval(Code, St),
     ?assert(meck:called(asobi_terrain_store, preload_chunks, '_')).
 
+%% --- to_storage_value coercion ---
+
+to_storage_value_scalars() ->
+    ?assertEqual(5, asobi_lua_api:to_storage_value(5)),
+    ?assertEqual(3.14, asobi_lua_api:to_storage_value(3.14)),
+    ?assertEqual(~"hello", asobi_lua_api:to_storage_value(~"hello")),
+    ?assertEqual(true, asobi_lua_api:to_storage_value(true)),
+    ?assertEqual(false, asobi_lua_api:to_storage_value(false)),
+    ?assertEqual(nil, asobi_lua_api:to_storage_value(nil)).
+
+to_storage_value_maps() ->
+    ?assertEqual(
+        #{~"k" => ~"v", ~"n" => 5},
+        asobi_lua_api:to_storage_value(#{~"k" => ~"v", ~"n" => 5})
+    ),
+    %% Luerl decodes maps to string-keyed proplists. The coercer must
+    %% turn that into an Erlang map so kura's jsonb encoder can serialise.
+    ?assertEqual(
+        #{~"k" => ~"v"},
+        asobi_lua_api:to_storage_value([{~"k", ~"v"}])
+    ).
+
+to_storage_value_arrays() ->
+    %% Luerl decodes Lua arrays to integer-keyed proplists.
+    ?assertEqual(
+        [~"a", ~"b", ~"c"],
+        asobi_lua_api:to_storage_value([{1, ~"a"}, {2, ~"b"}, {3, ~"c"}])
+    ),
+    %% Out-of-order pairs still produce a stable ordering by key.
+    ?assertEqual(
+        [~"a", ~"b", ~"c"],
+        asobi_lua_api:to_storage_value([{3, ~"c"}, {1, ~"a"}, {2, ~"b"}])
+    ).
+
+to_storage_value_nested() ->
+    %% { position = { x = 1, y = 2 }, tags = { "rare", "shiny" } }
+    Input = [
+        {~"position", [{~"x", 1}, {~"y", 2}]},
+        {~"tags", [{1, ~"rare"}, {2, ~"shiny"}]}
+    ],
+    Expected = #{
+        ~"position" => #{~"x" => 1, ~"y" => 2},
+        ~"tags" => [~"rare", ~"shiny"]
+    },
+    ?assertEqual(Expected, asobi_lua_api:to_storage_value(Input)).
+
+%% --- Storage round-trip: scalar values must reach the changeset ---
+
+storage_player_set_scalar() ->
+    storage_player_set_roundtrip("5", 5).
+
+storage_player_set_binary() ->
+    storage_player_set_roundtrip("\"dark\"", ~"dark").
+
+storage_player_set_array() ->
+    storage_player_set_roundtrip("{1, 2, 3}", [1, 2, 3]).
+
+-spec storage_player_set_roundtrip(string(), term()) -> ok.
+storage_player_set_roundtrip(LuaValueExpr, Expected) ->
+    St = install_api(),
+    meck:reset(asobi_repo),
+    meck:expect(asobi_repo, all, fun(_) -> {ok, []} end),
+    Code =
+        "local r = game.storage.player_set('p1', 'inv', 'k', " ++
+            LuaValueExpr ++
+            ")\nreturn r.ok ~= nil",
+    {ok, [true | _], _} = eval(Code, St),
+    %% kura_changeset:cast/4 receives the params map; meck:history captures
+    %% every call to asobi_repo:insert/1. Pull the most recent insert and
+    %% verify the value field round-trips intact.
+    History = meck:history(asobi_repo),
+    [{_, {asobi_repo, insert, [Changeset]}, _} | _] =
+        lists:reverse([H || H <- History, element(2, element(2, H)) =:= insert]),
+    ?assertEqual(Expected, changeset_param(Changeset, value)).
+
+%% Pull a named field out of a kura_changeset record. Position 5 holds
+%% the (normalised) params map per kura.hrl.
+-spec changeset_param(term(), atom()) -> term().
+changeset_param(CS, Field) when is_tuple(CS) ->
+    Params = element(5, CS),
+    maps:get(Field, Params).
+
 %% --- Helpers ---
 
 install_api() ->