diff --git a/rebar.config b/rebar.config
index bd09e12..f63df70 100644
--- a/rebar.config
+++ b/rebar.config
@@ -1,7 +1,7 @@
 %% Compiler Options ===========================================================
 {erl_opts, [
     %% Erlang releases after 17 don't put R in front of their name, and also require dict() to be written like dict:dict()
-    {platform_define, "^[0-9]+", namespaced_types},
+    {platform_define, "^R", non_namespaced_types},
     warn_export_all,
     warn_export_vars,
     warn_shadow_vars,
diff --git a/src/meck_proc.erl b/src/meck_proc.erl
index db01b06..cfb3050 100644
--- a/src/meck_proc.erl
+++ b/src/meck_proc.erl
@@ -47,10 +47,10 @@
 %%% Definitions
 %%%============================================================================
 
--ifdef(namespaced_types).
--type meck_dict() :: dict:dict().
--else.
+-ifdef(non_namespaced_types). % For older Erlang versions
 -type meck_dict() :: dict().
+-else.
+-type meck_dict() :: dict:dict().
 -endif.
 
 -record(state, {mod :: atom(),
diff --git a/test.config b/test.config
index 74bf444..69ed470 100644
--- a/test.config
+++ b/test.config
@@ -6,7 +6,7 @@
 %% Compiler Options ===========================================================
 {erl_opts, [
     %% Erlang releases after 17 don't put R in front of their name, and also require dict() to be written like dict:dict()
-    {platform_define, "^[0-9]+", namespaced_types},
+    {platform_define, "^R", non_namespaced_types},
     {platform_define, "^R(?!16B03)", cover_empty_compile_opts},
     warnings_as_errors,
     debug_info