diff --git a/source/blender/makesrna/intern/rna_wm.cc b/source/blender/makesrna/intern/rna_wm.cc
index 6300629b048..2bd5c837657 100644
--- a/source/blender/makesrna/intern/rna_wm.cc
+++ b/source/blender/makesrna/intern/rna_wm.cc
@@ -1610,8 +1610,8 @@ static bool rna_Operator_unregister(Main *bmain, StructRNA *type);
 
 /* `bpy_operator_wrap.cc` */
 
-extern "C" void BPY_RNA_operator_wrapper(wmOperatorType *ot, void *userdata);
-extern "C" void BPY_RNA_operator_macro_wrapper(wmOperatorType *ot, void *userdata);
+extern void BPY_RNA_operator_wrapper(wmOperatorType *ot, void *userdata);
+extern void BPY_RNA_operator_macro_wrapper(wmOperatorType *ot, void *userdata);
 
 static StructRNA *rna_Operator_register(Main *bmain,
                                         ReportList *reports,
diff --git a/source/blender/makesrna/intern/rna_wm_gizmo.cc b/source/blender/makesrna/intern/rna_wm_gizmo.cc
index 71f679fcad2..7fc6299f0b2 100644
--- a/source/blender/makesrna/intern/rna_wm_gizmo.cc
+++ b/source/blender/makesrna/intern/rna_wm_gizmo.cc
@@ -412,7 +412,7 @@ static PointerRNA rna_Gizmo_group_get(PointerRNA *ptr)
 #  ifdef WITH_PYTHON
 
 static bool rna_Gizmo_unregister(Main *bmain, StructRNA *type);
-extern "C" void BPY_RNA_gizmo_wrapper(wmGizmoType *gzgt, void *userdata);
+extern void BPY_RNA_gizmo_wrapper(wmGizmoType *gzgt, void *userdata);
 
 static StructRNA *rna_Gizmo_register(Main *bmain,
                                      ReportList *reports,
@@ -787,7 +787,7 @@ static void rna_gizmogroup_invoke_prepare_cb(const bContext *C,
   RNA_parameter_list_free(&list);
 }
 
-extern "C" void BPY_RNA_gizmogroup_wrapper(wmGizmoGroupType *gzgt, void *userdata);
+extern void BPY_RNA_gizmogroup_wrapper(wmGizmoGroupType *gzgt, void *userdata);
 static bool rna_GizmoGroup_unregister(Main *bmain, StructRNA *type);
 
 static StructRNA *rna_GizmoGroup_register(Main *bmain,
diff --git a/source/blender/python/intern/CMakeLists.txt b/source/blender/python/intern/CMakeLists.txt
index b4a1620fc26..ceaae60d74a 100644
--- a/source/blender/python/intern/CMakeLists.txt
+++ b/source/blender/python/intern/CMakeLists.txt
@@ -72,7 +72,7 @@ set(SRC
   bpy_utils_units.cc
   stubs.cc
 
-  bpy.h
+  bpy.hh
   bpy_app.hh
   bpy_app_alembic.hh
   bpy_app_build_options.hh
@@ -88,16 +88,16 @@ set(SRC
   bpy_app_translations.hh
   bpy_app_usd.hh
   bpy_capi_utils.h
-  bpy_cli_command.h
-  bpy_driver.h
-  bpy_gizmo_wrap.h
-  bpy_intern_string.h
-  bpy_library.h
-  bpy_msgbus.h
-  bpy_operator.h
-  bpy_operator_wrap.h
-  bpy_path.h
-  bpy_props.h
+  bpy_cli_command.hh
+  bpy_driver.hh
+  bpy_gizmo_wrap.hh
+  bpy_intern_string.hh
+  bpy_library.hh
+  bpy_msgbus.hh
+  bpy_operator.hh
+  bpy_operator_wrap.hh
+  bpy_path.hh
+  bpy_props.hh
   bpy_rna.hh
   bpy_rna_anim.hh
   bpy_rna_callback.hh
@@ -110,9 +110,9 @@ set(SRC
   bpy_rna_text.hh
   bpy_rna_types_capi.hh
   bpy_rna_ui.hh
-  bpy_traceback.h
-  bpy_utils_previews.h
-  bpy_utils_units.h
+  bpy_traceback.hh
+  bpy_utils_previews.hh
+  bpy_utils_units.hh
   ../BPY_extern.h
   ../BPY_extern_clog.h
   ../BPY_extern_python.h
diff --git a/source/blender/python/intern/bpy.cc b/source/blender/python/intern/bpy.cc
index ea56b55d993..dee0fffdc03 100644
--- a/source/blender/python/intern/bpy.cc
+++ b/source/blender/python/intern/bpy.cc
@@ -32,19 +32,19 @@
 
 #include "WM_api.hh" /* For #WM_ghost_backend */
 
-#include "bpy.h"
+#include "bpy.hh"
 #include "bpy_app.hh"
-#include "bpy_cli_command.h"
-#include "bpy_driver.h"
-#include "bpy_library.h"
-#include "bpy_operator.h"
-#include "bpy_props.h"
+#include "bpy_cli_command.hh"
+#include "bpy_driver.hh"
+#include "bpy_library.hh"
+#include "bpy_operator.hh"
+#include "bpy_props.hh"
 #include "bpy_rna.hh"
 #include "bpy_rna_data.hh"
 #include "bpy_rna_gizmo.hh"
 #include "bpy_rna_types_capi.hh"
-#include "bpy_utils_previews.h"
-#include "bpy_utils_units.h"
+#include "bpy_utils_previews.hh"
+#include "bpy_utils_units.hh"
 
 #include "../generic/py_capi_utils.h"
 #include "../generic/python_compat.h"
@@ -53,7 +53,7 @@
 /* external util modules */
 #include "../generic/idprop_py_api.h"
 #include "../generic/idprop_py_ui_api.h"
-#include "bpy_msgbus.h"
+#include "bpy_msgbus.hh"
 
 #ifdef WITH_FREESTYLE
 #  include "BPy_Freestyle.h"
diff --git a/source/blender/python/intern/bpy.h b/source/blender/python/intern/bpy.hh
similarity index 71%
rename from source/blender/python/intern/bpy.h
rename to source/blender/python/intern/bpy.hh
index cf38995b9e3..e70a1cbad45 100644
--- a/source/blender/python/intern/bpy.h
+++ b/source/blender/python/intern/bpy.hh
@@ -8,26 +8,18 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 struct bContext;
 
 /** Creates the `bpy` module and adds it to `sys.modules` for importing. */
-void BPy_init_modules(struct bContext *C);
+void BPy_init_modules(bContext *C);
 
 extern PyObject *bpy_package_py;
 
 /* `bpy_interface_atexit.cc` */
 
-void BPY_atexit_register(void);
-void BPY_atexit_unregister(void);
+void BPY_atexit_register();
+void BPY_atexit_unregister();
 
 extern struct CLG_LogRef *BPY_LOG_CONTEXT;
 extern struct CLG_LogRef *BPY_LOG_RNA;
 extern struct CLG_LogRef *BPY_LOG_INTERFACE;
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_app.cc b/source/blender/python/intern/bpy_app.cc
index 6b2c3b0a49e..278004f8959 100644
--- a/source/blender/python/intern/bpy_app.cc
+++ b/source/blender/python/intern/bpy_app.cc
@@ -27,7 +27,7 @@
 #include "bpy_app_translations.hh"
 
 #include "bpy_app_handlers.hh"
-#include "bpy_driver.h"
+#include "bpy_driver.hh"
 
 #include "BPY_extern_python.h" /* For #BPY_python_app_help_text_fn. */
 
diff --git a/source/blender/python/intern/bpy_cli_command.cc b/source/blender/python/intern/bpy_cli_command.cc
index 2cf29730baa..5610a174308 100644
--- a/source/blender/python/intern/bpy_cli_command.cc
+++ b/source/blender/python/intern/bpy_cli_command.cc
@@ -21,7 +21,7 @@
 #include "../generic/python_compat.h"
 #include "../generic/python_utildefines.h"
 
-#include "bpy_cli_command.h" /* Own include. */
+#include "bpy_cli_command.hh" /* Own include. */
 
 static const char *bpy_cli_command_capsule_name = "bpy_cli_command";
 static const char *bpy_cli_command_capsule_name_invalid = "bpy_cli_command<invalid>";
diff --git a/source/blender/python/intern/bpy_cli_command.h b/source/blender/python/intern/bpy_cli_command.hh
similarity index 78%
rename from source/blender/python/intern/bpy_cli_command.h
rename to source/blender/python/intern/bpy_cli_command.hh
index b7dac5ed068..7f5db8859cd 100644
--- a/source/blender/python/intern/bpy_cli_command.h
+++ b/source/blender/python/intern/bpy_cli_command.hh
@@ -8,13 +8,5 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 extern PyMethodDef BPY_cli_command_register_def;
 extern PyMethodDef BPY_cli_command_unregister_def;
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_driver.cc b/source/blender/python/intern/bpy_driver.cc
index 077125c8382..57180424872 100644
--- a/source/blender/python/intern/bpy_driver.cc
+++ b/source/blender/python/intern/bpy_driver.cc
@@ -28,9 +28,9 @@
 
 #include "bpy_rna_driver.hh" /* For #pyrna_driver_get_variable_value. */
 
-#include "bpy_intern_string.h"
+#include "bpy_intern_string.hh"
 
-#include "bpy_driver.h"
+#include "bpy_driver.hh"
 #include "bpy_rna.hh"
 
 #include "BPY_extern.h"
diff --git a/source/blender/python/intern/bpy_driver.h b/source/blender/python/intern/bpy_driver.hh
similarity index 89%
rename from source/blender/python/intern/bpy_driver.h
rename to source/blender/python/intern/bpy_driver.hh
index cc3c17fb6af..b4c9f5bf4d2 100644
--- a/source/blender/python/intern/bpy_driver.h
+++ b/source/blender/python/intern/bpy_driver.hh
@@ -8,17 +8,13 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #include <stdbool.h>
 
 /**
  * For faster execution we keep a special dictionary for py-drivers, with
  * the needed modules and aliases.
  */
-int bpy_pydriver_create_dict(void);
+int bpy_pydriver_create_dict();
 /**
  * For PyDrivers
  * (drivers using one-line Python expressions to express relationships between targets).
@@ -32,7 +28,3 @@ extern bool BPY_driver_secure_bytecode_test_ex(PyObject *expr_code,
 extern bool BPY_driver_secure_bytecode_test(PyObject *expr_code,
                                             PyObject *py_namespace,
                                             const bool verbose);
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_gizmo_wrap.cc b/source/blender/python/intern/bpy_gizmo_wrap.cc
index 1d624e474d6..8e3051cca64 100644
--- a/source/blender/python/intern/bpy_gizmo_wrap.cc
+++ b/source/blender/python/intern/bpy_gizmo_wrap.cc
@@ -24,8 +24,8 @@
 #include "RNA_define.hh"
 #include "RNA_enum_types.hh"
 
-#include "bpy_gizmo_wrap.h" /* own include */
-#include "bpy_intern_string.h"
+#include "bpy_gizmo_wrap.hh" /* own include */
+#include "bpy_intern_string.hh"
 #include "bpy_rna.hh"
 
 #include "../generic/py_capi_rna.h"
diff --git a/source/blender/python/intern/bpy_gizmo_wrap.h b/source/blender/python/intern/bpy_gizmo_wrap.hh
similarity index 51%
rename from source/blender/python/intern/bpy_gizmo_wrap.h
rename to source/blender/python/intern/bpy_gizmo_wrap.hh
index cd686ac32a1..87e1156044d 100644
--- a/source/blender/python/intern/bpy_gizmo_wrap.h
+++ b/source/blender/python/intern/bpy_gizmo_wrap.hh
@@ -11,14 +11,6 @@
 struct wmGizmoGroupType;
 struct wmGizmoType;
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 /* Exposed to RNA/WM API. */
-void BPY_RNA_gizmo_wrapper(struct wmGizmoType *gzt, void *userdata);
-void BPY_RNA_gizmogroup_wrapper(struct wmGizmoGroupType *gzgt, void *userdata);
-
-#ifdef __cplusplus
-}
-#endif
+void BPY_RNA_gizmo_wrapper(wmGizmoType *gzt, void *userdata);
+void BPY_RNA_gizmogroup_wrapper(wmGizmoGroupType *gzgt, void *userdata);
diff --git a/source/blender/python/intern/bpy_interface.cc b/source/blender/python/intern/bpy_interface.cc
index 0fe63be9a2f..d93dd205028 100644
--- a/source/blender/python/intern/bpy_interface.cc
+++ b/source/blender/python/intern/bpy_interface.cc
@@ -33,13 +33,13 @@
 
 #include "RNA_types.hh"
 
-#include "bpy.h"
+#include "bpy.hh"
 #include "bpy_capi_utils.h"
-#include "bpy_intern_string.h"
-#include "bpy_path.h"
-#include "bpy_props.h"
+#include "bpy_intern_string.hh"
+#include "bpy_path.hh"
+#include "bpy_props.hh"
 #include "bpy_rna.hh"
-#include "bpy_traceback.h"
+#include "bpy_traceback.hh"
 
 #include "bpy_app_translations.hh"
 
diff --git a/source/blender/python/intern/bpy_interface_atexit.cc b/source/blender/python/intern/bpy_interface_atexit.cc
index ee49380a91b..e2a196c5ad2 100644
--- a/source/blender/python/intern/bpy_interface_atexit.cc
+++ b/source/blender/python/intern/bpy_interface_atexit.cc
@@ -14,7 +14,7 @@
 
 #include "BLI_utildefines.h"
 
-#include "bpy.h" /* own include */
+#include "bpy.hh" /* own include */
 #include "bpy_capi_utils.h"
 
 #include "WM_api.hh"
diff --git a/source/blender/python/intern/bpy_interface_run.cc b/source/blender/python/intern/bpy_interface_run.cc
index 3d61c7532d8..58d5d96d473 100644
--- a/source/blender/python/intern/bpy_interface_run.cc
+++ b/source/blender/python/intern/bpy_interface_run.cc
@@ -27,8 +27,8 @@
 #include "BPY_extern_run.h"
 
 #include "bpy_capi_utils.h"
-#include "bpy_intern_string.h"
-#include "bpy_traceback.h"
+#include "bpy_intern_string.hh"
+#include "bpy_traceback.hh"
 
 #include "../generic/py_capi_utils.h"
 
diff --git a/source/blender/python/intern/bpy_intern_string.cc b/source/blender/python/intern/bpy_intern_string.cc
index 4b4c2aad566..c5009f84207 100644
--- a/source/blender/python/intern/bpy_intern_string.cc
+++ b/source/blender/python/intern/bpy_intern_string.cc
@@ -12,7 +12,7 @@
 
 #include <Python.h>
 
-#include "bpy_intern_string.h"
+#include "bpy_intern_string.hh"
 
 #include "BLI_utildefines.h"
 
diff --git a/source/blender/python/intern/bpy_intern_string.h b/source/blender/python/intern/bpy_intern_string.hh
similarity index 86%
rename from source/blender/python/intern/bpy_intern_string.h
rename to source/blender/python/intern/bpy_intern_string.hh
index a1f57c7e1ad..533a52db381 100644
--- a/source/blender/python/intern/bpy_intern_string.h
+++ b/source/blender/python/intern/bpy_intern_string.hh
@@ -8,12 +8,8 @@
  * \ingroup pythonintern
  */
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-void bpy_intern_string_init(void);
-void bpy_intern_string_exit(void);
+void bpy_intern_string_init();
+void bpy_intern_string_exit();
 
 extern PyObject *bpy_intern_str___annotations__;
 extern PyObject *bpy_intern_str___doc__;
@@ -32,7 +28,3 @@ extern PyObject *bpy_intern_str_register;
 extern PyObject *bpy_intern_str_self;
 extern PyObject *bpy_intern_str_depsgraph;
 extern PyObject *bpy_intern_str_unregister;
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_library.h b/source/blender/python/intern/bpy_library.hh
similarity index 70%
rename from source/blender/python/intern/bpy_library.h
rename to source/blender/python/intern/bpy_library.hh
index 73b2167f2ae..a24ca789712 100644
--- a/source/blender/python/intern/bpy_library.h
+++ b/source/blender/python/intern/bpy_library.hh
@@ -8,15 +8,7 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+int BPY_library_load_type_ready();
 
-int BPY_library_load_type_ready(void);
 extern PyMethodDef BPY_library_load_method_def;
-
 extern PyMethodDef BPY_library_write_method_def;
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_library_load.cc b/source/blender/python/intern/bpy_library_load.cc
index 49bdd2eb621..52b881fdf38 100644
--- a/source/blender/python/intern/bpy_library_load.cc
+++ b/source/blender/python/intern/bpy_library_load.cc
@@ -35,7 +35,7 @@
 #include "MEM_guardedalloc.h"
 
 #include "bpy_capi_utils.h"
-#include "bpy_library.h"
+#include "bpy_library.hh"
 
 #include "../generic/py_capi_utils.h"
 #include "../generic/python_compat.h"
diff --git a/source/blender/python/intern/bpy_library_write.cc b/source/blender/python/intern/bpy_library_write.cc
index 706927744fc..fab7c9f1aaa 100644
--- a/source/blender/python/intern/bpy_library_write.cc
+++ b/source/blender/python/intern/bpy_library_write.cc
@@ -29,7 +29,7 @@
 #include "RNA_types.hh"
 
 #include "bpy_capi_utils.h"
-#include "bpy_library.h" /* Declaration for #BPY_library_load_method_def */
+#include "bpy_library.hh" /* Declaration for #BPY_library_load_method_def */
 #include "bpy_rna.hh"
 
 #include "../generic/py_capi_utils.h"
diff --git a/source/blender/python/intern/bpy_msgbus.cc b/source/blender/python/intern/bpy_msgbus.cc
index 2db4da40e5a..36726cf1598 100644
--- a/source/blender/python/intern/bpy_msgbus.cc
+++ b/source/blender/python/intern/bpy_msgbus.cc
@@ -27,7 +27,7 @@
 #include "bpy_capi_utils.h"
 #include "bpy_rna.hh"
 
-#include "bpy_msgbus.h" /* own include */
+#include "bpy_msgbus.hh" /* own include */
 
 /* -------------------------------------------------------------------- */
 /** \name Internal Utils
diff --git a/source/blender/python/intern/bpy_utils_units.h b/source/blender/python/intern/bpy_msgbus.hh
similarity index 60%
rename from source/blender/python/intern/bpy_utils_units.h
rename to source/blender/python/intern/bpy_msgbus.hh
index 1533f2c25ea..a6de5780d94 100644
--- a/source/blender/python/intern/bpy_utils_units.h
+++ b/source/blender/python/intern/bpy_msgbus.hh
@@ -8,12 +8,4 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-PyObject *BPY_utils_units(void);
-
-#ifdef __cplusplus
-}
-#endif
+PyObject *BPY_msgbus_module();
diff --git a/source/blender/python/intern/bpy_operator.cc b/source/blender/python/intern/bpy_operator.cc
index ea933a9692d..940530481e5 100644
--- a/source/blender/python/intern/bpy_operator.cc
+++ b/source/blender/python/intern/bpy_operator.cc
@@ -27,8 +27,8 @@
 
 #include "BPY_extern.h"
 #include "bpy_capi_utils.h"
-#include "bpy_operator.h"
-#include "bpy_operator_wrap.h"
+#include "bpy_operator.hh"
+#include "bpy_operator_wrap.hh"
 #include "bpy_rna.hh" /* for setting argument properties & type method `get_rna_type`. */
 
 #include "RNA_access.hh"
diff --git a/source/blender/python/intern/bpy_operator.h b/source/blender/python/intern/bpy_operator.hh
similarity index 68%
rename from source/blender/python/intern/bpy_operator.h
rename to source/blender/python/intern/bpy_operator.hh
index 61b53511a4e..bfcd86b7789 100644
--- a/source/blender/python/intern/bpy_operator.h
+++ b/source/blender/python/intern/bpy_operator.hh
@@ -8,20 +8,12 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 extern PyTypeObject pyop_base_Type;
 
 #define BPy_OperatorBase_Check(v) (PyObject_TypeCheck(v, &pyop_base_Type))
 
-typedef struct {
+struct BPy_OperatorBase {
   PyObject_HEAD /* Required Python macro. */
-} BPy_OperatorBase;
+};
 
-PyObject *BPY_operator_module(void);
-
-#ifdef __cplusplus
-}
-#endif
+PyObject *BPY_operator_module();
diff --git a/source/blender/python/intern/bpy_operator_wrap.cc b/source/blender/python/intern/bpy_operator_wrap.cc
index 9d4b8ffdc90..b77c9c4d08f 100644
--- a/source/blender/python/intern/bpy_operator_wrap.cc
+++ b/source/blender/python/intern/bpy_operator_wrap.cc
@@ -22,8 +22,8 @@
 #include "RNA_define.hh"
 #include "RNA_prototypes.hh"
 
-#include "bpy_intern_string.h"
-#include "bpy_operator_wrap.h" /* own include */
+#include "bpy_intern_string.hh"
+#include "bpy_operator_wrap.hh" /* own include */
 #include "bpy_rna.hh"
 
 static void operator_properties_init(wmOperatorType *ot)
diff --git a/source/blender/python/intern/bpy_operator_wrap.h b/source/blender/python/intern/bpy_operator_wrap.hh
similarity index 77%
rename from source/blender/python/intern/bpy_operator_wrap.h
rename to source/blender/python/intern/bpy_operator_wrap.hh
index 3df24160794..30dd961baef 100644
--- a/source/blender/python/intern/bpy_operator_wrap.h
+++ b/source/blender/python/intern/bpy_operator_wrap.hh
@@ -10,10 +10,6 @@
 
 struct wmOperatorType;
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 /**
  * These are used for operator methods, used by `bpy_operator.cc`.
  *
@@ -27,13 +23,9 @@ PyObject *PYOP_wrap_macro_define(PyObject *self, PyObject *args);
  * Generic function used by all Python defined operators
  * it's passed as an argument to #WM_operatortype_append_ptr in for operator registration.
  */
-void BPY_RNA_operator_wrapper(struct wmOperatorType *ot, void *userdata);
+void BPY_RNA_operator_wrapper(wmOperatorType *ot, void *userdata);
 /**
  * Generic function used by all Python defined macro-operators
  * it's passed as an argument to #WM_operatortype_append_ptr in for operator registration.
  */
-void BPY_RNA_operator_macro_wrapper(struct wmOperatorType *ot, void *userdata);
-
-#ifdef __cplusplus
-}
-#endif
+void BPY_RNA_operator_macro_wrapper(wmOperatorType *ot, void *userdata);
diff --git a/source/blender/python/intern/bpy_path.cc b/source/blender/python/intern/bpy_path.cc
index d4338f5196f..f2106351e2b 100644
--- a/source/blender/python/intern/bpy_path.cc
+++ b/source/blender/python/intern/bpy_path.cc
@@ -12,7 +12,7 @@
 
 #include "BLI_utildefines.h"
 
-#include "bpy_path.h"
+#include "bpy_path.hh"
 
 #include "../generic/py_capi_utils.h"
 
diff --git a/source/blender/python/intern/bpy_msgbus.h b/source/blender/python/intern/bpy_path.hh
similarity index 59%
rename from source/blender/python/intern/bpy_msgbus.h
rename to source/blender/python/intern/bpy_path.hh
index 30490fce41e..620d81f32a7 100644
--- a/source/blender/python/intern/bpy_msgbus.h
+++ b/source/blender/python/intern/bpy_path.hh
@@ -8,12 +8,4 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-PyObject *BPY_msgbus_module(void);
-
-#ifdef __cplusplus
-}
-#endif
+PyObject *BPyInit__bpy_path();
diff --git a/source/blender/python/intern/bpy_props.cc b/source/blender/python/intern/bpy_props.cc
index b2bef2ba352..8a641ff7e50 100644
--- a/source/blender/python/intern/bpy_props.cc
+++ b/source/blender/python/intern/bpy_props.cc
@@ -24,7 +24,7 @@
 #include "BLI_utildefines.h"
 
 #include "bpy_capi_utils.h"
-#include "bpy_props.h"
+#include "bpy_props.hh"
 #include "bpy_rna.hh"
 
 #include "RNA_access.hh"
diff --git a/source/blender/python/intern/bpy_props.h b/source/blender/python/intern/bpy_props.hh
similarity index 83%
rename from source/blender/python/intern/bpy_props.h
rename to source/blender/python/intern/bpy_props.hh
index af3e8b7705f..d0628a53c95 100644
--- a/source/blender/python/intern/bpy_props.h
+++ b/source/blender/python/intern/bpy_props.hh
@@ -8,22 +8,18 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-PyObject *BPY_rna_props(void);
+PyObject *BPY_rna_props();
 /**
  * Run this on exit, clearing all Python callback users and disable the RNA callback,
  * as it would be called after Python has already finished.
  */
-void BPY_rna_props_clear_all(void);
+void BPY_rna_props_clear_all();
 
 PyObject *BPy_PointerProperty(PyObject *self, PyObject *args, PyObject *kw);
 PyObject *BPy_CollectionProperty(PyObject *self, PyObject *args, PyObject *kw);
 StructRNA *pointer_type_from_py(PyObject *value, const char *error_prefix);
 
-typedef struct {
+struct BPy_PropDeferred {
   PyObject_HEAD
   /**
    * Internally a #PyCFunctionObject type.
@@ -31,13 +27,9 @@ typedef struct {
    */
   void *fn;
   PyObject *kw;
-} BPy_PropDeferred;
+};
 
 extern PyTypeObject bpy_prop_deferred_Type;
 #define BPy_PropDeferred_CheckTypeExact(v) (Py_TYPE(v) == &bpy_prop_deferred_Type)
 
 #define PYRNA_STACK_ARRAY RNA_STACK_ARRAY
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_rna.cc b/source/blender/python/intern/bpy_rna.cc
index 68bfe029cc3..0a65039879c 100644
--- a/source/blender/python/intern/bpy_rna.cc
+++ b/source/blender/python/intern/bpy_rna.cc
@@ -31,8 +31,8 @@
 #include "BPY_extern_clog.h"
 
 #include "bpy_capi_utils.h"
-#include "bpy_intern_string.h"
-#include "bpy_props.h"
+#include "bpy_intern_string.hh"
+#include "bpy_props.hh"
 #include "bpy_rna.hh"
 #include "bpy_rna_anim.hh"
 #include "bpy_rna_callback.hh"
diff --git a/source/blender/python/intern/bpy_rna_types_capi.cc b/source/blender/python/intern/bpy_rna_types_capi.cc
index 3fe52a686af..e6571f9bd7b 100644
--- a/source/blender/python/intern/bpy_rna_types_capi.cc
+++ b/source/blender/python/intern/bpy_rna_types_capi.cc
@@ -21,7 +21,7 @@
 
 #include "BLI_utildefines.h"
 
-#include "bpy_library.h"
+#include "bpy_library.hh"
 #include "bpy_rna.hh"
 #include "bpy_rna_callback.hh"
 #include "bpy_rna_context.hh"
diff --git a/source/blender/python/intern/bpy_traceback.cc b/source/blender/python/intern/bpy_traceback.cc
index 685baf6826d..577259681b6 100644
--- a/source/blender/python/intern/bpy_traceback.cc
+++ b/source/blender/python/intern/bpy_traceback.cc
@@ -18,7 +18,7 @@
 #  include "BLI_string.h" /* BLI_strcasecmp */
 #endif
 
-#include "bpy_traceback.h"
+#include "bpy_traceback.hh"
 
 #define MAKE_PY_IDENTIFIER_EX(varname, value) static _Py_Identifier varname{value, -1};
 #define MAKE_PY_IDENTIFIER(varname) MAKE_PY_IDENTIFIER_EX(PyId_##varname, #varname)
diff --git a/source/blender/python/intern/bpy_traceback.h b/source/blender/python/intern/bpy_traceback.hh
similarity index 80%
rename from source/blender/python/intern/bpy_traceback.h
rename to source/blender/python/intern/bpy_traceback.hh
index dcfcaa04a21..0342ffa1717 100644
--- a/source/blender/python/intern/bpy_traceback.h
+++ b/source/blender/python/intern/bpy_traceback.hh
@@ -8,13 +8,5 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 bool python_script_error_jump(
     const char *filepath, int *r_lineno, int *r_offset, int *r_lineno_end, int *r_offset_end);
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/python/intern/bpy_utils_previews.cc b/source/blender/python/intern/bpy_utils_previews.cc
index 811a8bdfea4..95f0d298e6c 100644
--- a/source/blender/python/intern/bpy_utils_previews.cc
+++ b/source/blender/python/intern/bpy_utils_previews.cc
@@ -20,7 +20,7 @@
 #include "RNA_prototypes.hh"
 
 #include "bpy_rna.hh"
-#include "bpy_utils_previews.h"
+#include "bpy_utils_previews.hh"
 
 #include "../generic/py_capi_utils.h"
 
diff --git a/source/blender/python/intern/bpy_path.h b/source/blender/python/intern/bpy_utils_previews.hh
similarity index 59%
rename from source/blender/python/intern/bpy_path.h
rename to source/blender/python/intern/bpy_utils_previews.hh
index 29111d5981f..a23a159be13 100644
--- a/source/blender/python/intern/bpy_path.h
+++ b/source/blender/python/intern/bpy_utils_previews.hh
@@ -8,12 +8,4 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-PyObject *BPyInit__bpy_path(void);
-
-#ifdef __cplusplus
-}
-#endif
+PyObject *BPY_utils_previews_module();
diff --git a/source/blender/python/intern/bpy_utils_units.cc b/source/blender/python/intern/bpy_utils_units.cc
index 66c89a69160..dbbf45a584f 100644
--- a/source/blender/python/intern/bpy_utils_units.cc
+++ b/source/blender/python/intern/bpy_utils_units.cc
@@ -18,7 +18,7 @@
 #include "BLI_string.h"
 #include "BLI_utildefines.h"
 
-#include "bpy_utils_units.h"
+#include "bpy_utils_units.hh"
 
 #include "../generic/py_capi_utils.h"
 #include "../generic/python_compat.h"
diff --git a/source/blender/python/intern/bpy_utils_previews.h b/source/blender/python/intern/bpy_utils_units.hh
similarity index 57%
rename from source/blender/python/intern/bpy_utils_previews.h
rename to source/blender/python/intern/bpy_utils_units.hh
index 5c486eba499..75cfa39254b 100644
--- a/source/blender/python/intern/bpy_utils_previews.h
+++ b/source/blender/python/intern/bpy_utils_units.hh
@@ -8,12 +8,4 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-PyObject *BPY_utils_previews_module(void);
-
-#ifdef __cplusplus
-}
-#endif
+PyObject *BPY_utils_units();