diff --git a/src/background.c b/src/background.c
index 9ca7406dc..2c6c0988d 100644
--- a/src/background.c
+++ b/src/background.c
@@ -775,7 +775,7 @@ handle_request_background_in_thread_func (GTask *task,
                                           gpointer task_data,
                                           GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   GVariant *options;
   const char *id;
   Permission permission;
diff --git a/src/camera.c b/src/camera.c
index 376307ef2..afac07780 100644
--- a/src/camera.c
+++ b/src/camera.c
@@ -164,7 +164,7 @@ handle_access_camera_in_thread_func (GTask *task,
                                      gpointer task_data,
                                      GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   gboolean allowed;
 
   allowed = query_permission_sync (request);
diff --git a/src/clipboard.c b/src/clipboard.c
index 51879a317..136d01d34 100644
--- a/src/clipboard.c
+++ b/src/clipboard.c
@@ -80,7 +80,7 @@ handle_request_clipboard (XdpDbusClipboard *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_remote_desktop_session (session))
+  if (!IS_REMOTE_DESKTOP_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -88,7 +88,7 @@ handle_request_clipboard (XdpDbusClipboard *object,
                                              "Invalid session type");
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
-  remote_desktop_session = (RemoteDesktopSession *)session;
+  remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   if (!remote_desktop_session_can_request_clipboard (remote_desktop_session))
     {
@@ -130,7 +130,7 @@ handle_set_selection (XdpDbusClipboard *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_remote_desktop_session (session))
+  if (!IS_REMOTE_DESKTOP_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -139,7 +139,7 @@ handle_set_selection (XdpDbusClipboard *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
   else if (!remote_desktop_session_is_clipboard_enabled (
-             (RemoteDesktopSession *)session))
+             REMOTE_DESKTOP_SESSION (session)))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -240,7 +240,7 @@ handle_selection_write (XdpDbusClipboard *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_remote_desktop_session (session))
+  if (!IS_REMOTE_DESKTOP_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -249,7 +249,7 @@ handle_selection_write (XdpDbusClipboard *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
   else if (!remote_desktop_session_is_clipboard_enabled (
-             (RemoteDesktopSession *)session))
+             REMOTE_DESKTOP_SESSION (session)))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -291,7 +291,7 @@ handle_selection_write_done (XdpDbusClipboard *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_remote_desktop_session (session))
+  if (!IS_REMOTE_DESKTOP_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -300,7 +300,7 @@ handle_selection_write_done (XdpDbusClipboard *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
   else if (!remote_desktop_session_is_clipboard_enabled (
-             (RemoteDesktopSession *)session))
+             REMOTE_DESKTOP_SESSION (session)))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -381,7 +381,7 @@ handle_selection_read (XdpDbusClipboard *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_remote_desktop_session (session))
+  if (!IS_REMOTE_DESKTOP_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -390,7 +390,7 @@ handle_selection_read (XdpDbusClipboard *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
   else if (!remote_desktop_session_is_clipboard_enabled (
-             (RemoteDesktopSession *)session))
+              REMOTE_DESKTOP_SESSION (session)))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -452,8 +452,7 @@ selection_transfer_cb (XdpDbusImplClipboard *impl,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  RemoteDesktopSession *remote_desktop_session =
-    (RemoteDesktopSession *)session;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   if (remote_desktop_session &&
       remote_desktop_session_is_clipboard_enabled (remote_desktop_session) &&
@@ -489,8 +488,7 @@ selection_owner_changed_cb (XdpDbusImplClipboard *impl,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  RemoteDesktopSession *remote_desktop_session =
-    (RemoteDesktopSession *)session;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   if (remote_desktop_session &&
       remote_desktop_session_is_clipboard_enabled (remote_desktop_session) &&
diff --git a/src/global-shortcuts.c b/src/global-shortcuts.c
index ce5eb928f..c95d4da46 100644
--- a/src/global-shortcuts.c
+++ b/src/global-shortcuts.c
@@ -73,10 +73,23 @@ GType global_shortcuts_session_get_type (void);
 
 G_DEFINE_TYPE (GlobalShortcutsSession, global_shortcuts_session, session_get_type ())
 
+G_GNUC_UNUSED static inline GlobalShortcutsSession *
+GLOBAL_SHORTCUTS_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, global_shortcuts_session_get_type (), GlobalShortcutsSession);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_GLOBAL_SHORTCUTS_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, global_shortcuts_session_get_type ());
+}
+
 static void
 global_shortcuts_session_close (Session *session)
 {
-  GlobalShortcutsSession *global_shortcuts_session = (GlobalShortcutsSession *)session;
+  GlobalShortcutsSession *global_shortcuts_session =
+    GLOBAL_SHORTCUTS_SESSION (session);
 
   global_shortcuts_session->closed = TRUE;
 }
@@ -133,7 +146,7 @@ global_shortcuts_session_new (GVariant *options,
   if (session)
     g_debug ("global shortcuts session owned by '%s' created", session->sender);
 
-  return (GlobalShortcutsSession *) session;
+  return GLOBAL_SHORTCUTS_SESSION (session);
 }
 
 static void
@@ -253,7 +266,7 @@ handle_create_session (XdpDbusGlobalShortcuts *object,
   request_set_impl_request (request, impl_request);
   request_export (request, g_dbus_method_invocation_get_connection (invocation));
 
-  session = (Session *)global_shortcuts_session_new (options, request, &error);
+  session = SESSION (global_shortcuts_session_new (options, request, &error));
   if (!session)
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
@@ -593,7 +606,8 @@ activated_cb (XdpDbusImplGlobalShortcuts *impl,
 {
   GDBusConnection *connection = g_dbus_proxy_get_connection (G_DBUS_PROXY (impl));
   g_autoptr(Session) session = lookup_session (session_id);
-  GlobalShortcutsSession *global_shortcuts_session = (GlobalShortcutsSession *)session;
+  GlobalShortcutsSession *global_shortcuts_session =
+    GLOBAL_SHORTCUTS_SESSION (session);
 
   g_debug ("Received activated %s for %s", session_id, shortcut_id);
 
@@ -619,7 +633,8 @@ deactivated_cb (XdpDbusImplGlobalShortcuts *impl,
 {
   GDBusConnection *connection = g_dbus_proxy_get_connection (G_DBUS_PROXY (impl));
   g_autoptr(Session) session = lookup_session (session_id);
-  GlobalShortcutsSession *global_shortcuts_session = (GlobalShortcutsSession *)session;
+  GlobalShortcutsSession *global_shortcuts_session =
+    GLOBAL_SHORTCUTS_SESSION (session);
 
   g_debug ("Received deactivated %s for %s", session_id, shortcut_id);
 
@@ -643,7 +658,8 @@ shortcuts_changed_cb (XdpDbusImplGlobalShortcuts *impl,
 {
   GDBusConnection *connection = g_dbus_proxy_get_connection (G_DBUS_PROXY (impl));
   g_autoptr(Session) session = lookup_session (session_id);
-  GlobalShortcutsSession *global_shortcuts_session = (GlobalShortcutsSession *)session;
+  GlobalShortcutsSession *global_shortcuts_session =
+    GLOBAL_SHORTCUTS_SESSION (session);
 
   g_debug ("Received ShortcutsChanged %s", session_id);
 
diff --git a/src/inhibit.c b/src/inhibit.c
index a22e9483d..333431dfb 100644
--- a/src/inhibit.c
+++ b/src/inhibit.c
@@ -138,7 +138,7 @@ handle_inhibit_in_thread_func (GTask *task,
                                gpointer task_data,
                                GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   const char *window;
   guint32 flags;
   GVariant *options;
@@ -265,10 +265,22 @@ GType inhibit_session_get_type (void);
 
 G_DEFINE_TYPE (InhibitSession, inhibit_session, session_get_type ())
 
+G_GNUC_UNUSED static inline InhibitSession *
+INHIBIT_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, inhibit_session_get_type (), InhibitSession);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_INHIBIT_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, inhibit_session_get_type ());
+}
+
 static void
 inhibit_session_close (Session *session)
 {
-  InhibitSession *inhibit_session = (InhibitSession *)session;
+  InhibitSession *inhibit_session = INHIBIT_SESSION (session);
 
   inhibit_session->closed = TRUE;
 
@@ -421,7 +433,7 @@ handle_create_monitor (XdpDbusInhibit *object,
   request_set_impl_request (request, impl_request);
   request_export (request, g_dbus_method_invocation_get_connection (invocation));
 
-  session = (Session *)inhibit_session_new (arg_options, request, &error);
+  session = SESSION (inhibit_session_new (arg_options, request, &error));
   if (!session)
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
@@ -495,7 +507,7 @@ state_changed_cb (XdpDbusImplInhibit *impl,
 {
   GDBusConnection *connection = g_dbus_proxy_get_connection (G_DBUS_PROXY (impl));
   g_autoptr(Session) session = lookup_session (session_id);
-  InhibitSession *inhibit_session = (InhibitSession *)session;
+  InhibitSession *inhibit_session = INHIBIT_SESSION (session);
   gboolean active = FALSE;
   guint32 session_state = 0;
 
diff --git a/src/input-capture.c b/src/input-capture.c
index 65101a68f..89bf393dd 100644
--- a/src/input-capture.c
+++ b/src/input-capture.c
@@ -84,10 +84,16 @@ GType input_capture_session_get_type (void);
 
 G_DEFINE_TYPE (InputCaptureSession, input_capture_session, session_get_type ())
 
-static gboolean
-is_input_capture_session (Session *session)
+G_GNUC_UNUSED static inline InputCaptureSession *
+INPUT_CAPTURE_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, input_capture_session_get_type (), InputCaptureSession);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_INPUT_CAPTURE_SESSION (gpointer ptr)
 {
-  return G_TYPE_CHECK_INSTANCE_TYPE (session, input_capture_session_get_type ());
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, input_capture_session_get_type ());
 }
 
 static InputCaptureSession *
@@ -255,7 +261,7 @@ handle_create_session (XdpDbusInputCapture   *object,
   request_set_impl_request (request, impl_request);
   request_export (request, g_dbus_method_invocation_get_connection (invocation));
 
-  session = (Session *)input_capture_session_new (arg_options, request, &error);
+  session = SESSION (input_capture_session_new (arg_options, request, &error));
   if (!session)
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
@@ -305,7 +311,7 @@ get_zones_done (GObject      *source_object,
   gboolean should_close_session;
   uint32_t response = 2;
 
-  request = (Request *)data;
+  request = REQUEST (data);
 
   REQUEST_AUTOLOCK (request);
 
@@ -376,7 +382,7 @@ handle_get_zones (XdpDbusInputCapture   *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -385,7 +391,7 @@ handle_get_zones (XdpDbusInputCapture   *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-  input_capture_session = (InputCaptureSession *)session;
+  input_capture_session = INPUT_CAPTURE_SESSION (session);
 
   switch (input_capture_session->state)
     {
@@ -460,7 +466,7 @@ set_pointer_barriers_done (GObject      *source_object,
   Session *session;
   uint32_t response = 2;
 
-  request = (Request *)data;
+  request = REQUEST (data);
 
   REQUEST_AUTOLOCK (request);
 
@@ -531,7 +537,7 @@ handle_set_pointer_barriers (XdpDbusInputCapture   *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -540,7 +546,7 @@ handle_set_pointer_barriers (XdpDbusInputCapture   *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-  input_capture_session = (InputCaptureSession *)session;
+  input_capture_session = INPUT_CAPTURE_SESSION (session);
 
   switch (input_capture_session->state)
     {
@@ -632,7 +638,7 @@ handle_enable (XdpDbusInputCapture   *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -641,7 +647,7 @@ handle_enable (XdpDbusInputCapture   *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-   input_capture_session = (InputCaptureSession *)session;
+   input_capture_session = INPUT_CAPTURE_SESSION (session);
 
    switch (input_capture_session->state)
      {
@@ -733,7 +739,7 @@ handle_disable (XdpDbusInputCapture   *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -742,7 +748,7 @@ handle_disable (XdpDbusInputCapture   *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-   input_capture_session = (InputCaptureSession *)session;
+   input_capture_session = INPUT_CAPTURE_SESSION (session);
 
    switch (input_capture_session->state)
      {
@@ -834,7 +840,7 @@ handle_release (XdpDbusInputCapture   *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -843,7 +849,7 @@ handle_release (XdpDbusInputCapture   *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-  input_capture_session = (InputCaptureSession *)session;
+  input_capture_session = INPUT_CAPTURE_SESSION (session);
 
   switch (input_capture_session->state)
     {
@@ -934,7 +940,7 @@ handle_connect_to_eis (XdpDbusInputCapture   *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -943,7 +949,7 @@ handle_connect_to_eis (XdpDbusInputCapture   *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-  input_capture_session = (InputCaptureSession *)session;
+  input_capture_session = INPUT_CAPTURE_SESSION (session);
 
   switch (input_capture_session->state)
     {
@@ -1027,7 +1033,7 @@ on_disabled_cb (XdpDbusImplInputCapture *impl,
   g_autoptr(Session) session = lookup_session (session_id);
   InputCaptureSession *input_capture_session;
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_critical ("Invalid session type for signal");
       return;
@@ -1060,7 +1066,7 @@ on_activated_cb (XdpDbusImplInputCapture *impl,
   g_autoptr(Session) session = lookup_session (session_id);
   InputCaptureSession *input_capture_session;
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_critical ("Invalid session type for signal");
       return;
@@ -1092,7 +1098,7 @@ on_deactivated_cb (XdpDbusImplInputCapture *impl,
   g_autoptr(Session) session = lookup_session (session_id);
   InputCaptureSession *input_capture_session;
 
-  if (!is_input_capture_session (session))
+  if (!IS_INPUT_CAPTURE_SESSION (session))
     {
       g_critical ("Invalid session type for signal");
       return;
@@ -1142,7 +1148,7 @@ input_capture_class_init (InputCaptureClass *klass)
 static void
 input_capture_session_close (Session *session)
 {
-  InputCaptureSession *input_capture_session = (InputCaptureSession *)session;
+  InputCaptureSession *input_capture_session = INPUT_CAPTURE_SESSION (session);
 
   input_capture_session->state = INPUT_CAPTURE_SESSION_STATE_CLOSED;
 
diff --git a/src/location.c b/src/location.c
index 56cdfddcd..a6c3781dc 100644
--- a/src/location.c
+++ b/src/location.c
@@ -73,6 +73,18 @@ GType location_session_get_type (void);
 
 G_DEFINE_TYPE (LocationSession, location_session, session_get_type ())
 
+G_GNUC_UNUSED static inline LocationSession *
+LOCATION_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, location_session_get_type (), LocationSession);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_LOCATION_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, location_session_get_type ());
+}
+
 static void
 location_session_init (LocationSession *session)
 {
@@ -84,7 +96,7 @@ location_session_init (LocationSession *session)
 static void
 location_session_close (Session *session)
 {
-  LocationSession *loc_session = (LocationSession *)session;
+  LocationSession *loc_session = LOCATION_SESSION (session);
 
   loc_session->state = LOCATION_SESSION_STATE_CLOSED;
 
@@ -97,7 +109,7 @@ location_session_close (Session *session)
 static void
 location_session_finalize (GObject *object)
 {
-  LocationSession *loc_session = (LocationSession *)object;
+  LocationSession *loc_session = LOCATION_SESSION (object);
 
   g_clear_object (&loc_session->client);
 
@@ -233,7 +245,7 @@ location_session_start (LocationSession *loc_session)
 
   g_debug ("location session '%s', GeoClue client '%s'", ((Session*)loc_session)->id, client_id);
   g_debug ("location session '%s', distance-threshold %d, time-threshold %d, accuracy %s",
-           ((Session *)loc_session)->id,
+           SESSION (loc_session)->id,
            loc_session->distance_threshold,
            loc_session->time_threshold,
            gclue_accuracy_level_to_string (loc_session->accuracy));
@@ -411,7 +423,8 @@ handle_create_session (XdpDbusLocation *object,
                        GVariant *arg_options)
 {
   g_autoptr(GError) error = NULL;
-  LocationSession *session;
+  LocationSession *loc_session;
+  Session *session;
   guint threshold;
   guint accuracy;
 
@@ -425,31 +438,33 @@ handle_create_session (XdpDbusLocation *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-  session = location_session_new (arg_options, invocation, &error);
-  if (!session)
+  loc_session = location_session_new (arg_options, invocation, &error);
+  if (!loc_session)
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
+  session = SESSION (loc_session);
+
   if (g_variant_lookup (arg_options, "distance-threshold", "u", &threshold))
-    session->distance_threshold = threshold;
+    loc_session->distance_threshold = threshold;
   if (g_variant_lookup (arg_options, "time-threshold", "u", &threshold))
-    session->time_threshold = threshold;
+    loc_session->time_threshold = threshold;
   if (g_variant_lookup (arg_options, "accuracy", "u", &accuracy))
     {
       if (accuracy == 0)
-        session->accuracy = GCLUE_ACCURACY_LEVEL_NONE;
+        loc_session->accuracy = GCLUE_ACCURACY_LEVEL_NONE;
       else if (accuracy == 1)
-        session->accuracy = GCLUE_ACCURACY_LEVEL_COUNTRY;
+        loc_session->accuracy = GCLUE_ACCURACY_LEVEL_COUNTRY;
       else if (accuracy == 2)
-        session->accuracy = GCLUE_ACCURACY_LEVEL_CITY;
+        loc_session->accuracy = GCLUE_ACCURACY_LEVEL_CITY;
       else if (accuracy == 3)
-        session->accuracy = GCLUE_ACCURACY_LEVEL_NEIGHBORHOOD;
+        loc_session->accuracy = GCLUE_ACCURACY_LEVEL_NEIGHBORHOOD;
       else if (accuracy == 4)
-        session->accuracy = GCLUE_ACCURACY_LEVEL_STREET;
+        loc_session->accuracy = GCLUE_ACCURACY_LEVEL_STREET;
       else if (accuracy == 5)
-        session->accuracy = GCLUE_ACCURACY_LEVEL_EXACT;
+        loc_session->accuracy = GCLUE_ACCURACY_LEVEL_EXACT;
       else
         {
           g_dbus_method_invocation_return_error (invocation,
@@ -460,18 +475,18 @@ handle_create_session (XdpDbusLocation *object,
         }
     }
 
-  if (!session_export ((Session *)session, &error))
+  if (!session_export (session, &error))
     {
        g_warning ("Failed to export session: %s", error->message);
-       session_close ((Session *)session, FALSE);
+       session_close (session, FALSE);
     }
   else
     {
-      g_debug ("CreateSession new session '%s'",  ((Session *)session)->id);
-      session_register ((Session *)session);
+      g_debug ("CreateSession new session '%s'",  (session)->id);
+      session_register (session);
     }
 
-  xdp_dbus_location_complete_create_session (object, invocation, ((Session *)session)->id);
+  xdp_dbus_location_complete_create_session (object, invocation, (session)->id);
 
   return G_DBUS_METHOD_INVOCATION_HANDLED;
 }
@@ -484,7 +499,7 @@ handle_start_in_thread_func (GTask *task,
                              gpointer task_data,
                              GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   const char *parent_window;
   const char *id;
   gint64 last_used = 0;
@@ -499,7 +514,7 @@ handle_start_in_thread_func (GTask *task,
   session = g_object_get_qdata (G_OBJECT (request), quark_request_session);
   SESSION_AUTOLOCK_UNREF (g_object_ref (session));
   g_object_set_qdata (G_OBJECT (request), quark_request_session, NULL);
-  loc_session = (LocationSession *)session;
+  loc_session = LOCATION_SESSION (session);
 
   parent_window = (const char *)g_object_get_data (G_OBJECT (request), "parent-window");
 
@@ -609,7 +624,7 @@ handle_start_in_thread_func (GTask *task,
       loc_session->accuracy = accuracy;
     }
 
-  if (location_session_start ((LocationSession*)session))
+  if (location_session_start (loc_session))
     response = 0;
   else
     response = 2;
@@ -630,7 +645,7 @@ handle_start_in_thread_func (GTask *task,
   if (response != 0)
     {
        g_debug ("closing session");
-       session_close ((Session *)session, FALSE);
+       session_close (session, FALSE);
     }
 }
 
@@ -670,7 +685,7 @@ handle_start (XdpDbusLocation *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  loc_session = (LocationSession *)session;
+  loc_session = LOCATION_SESSION (session);
   switch (loc_session->state)
     {
     case LOCATION_SESSION_STATE_INIT:
diff --git a/src/open-uri.c b/src/open-uri.c
index b3c1bc876..2b106657e 100644
--- a/src/open-uri.c
+++ b/src/open-uri.c
@@ -350,7 +350,7 @@ send_response_in_thread_func (GTask *task,
                               gpointer task_data,
                               GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   guint response;
   GVariant *options;
   const char *choice;
@@ -591,7 +591,7 @@ handle_open_in_thread_func (GTask *task,
                             gpointer task_data,
                             GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   const char *parent_window;
   const char *app_id = xdp_app_info_get_id (request->app_info);
   const char *activation_token;
diff --git a/src/remote-desktop.c b/src/remote-desktop.c
index f615b28a7..55abfa118 100644
--- a/src/remote-desktop.c
+++ b/src/remote-desktop.c
@@ -107,17 +107,8 @@ typedef struct _RemoteDesktopSessionClass
   SessionClass parent_class;
 } RemoteDesktopSessionClass;
 
-GType remote_desktop_session_get_type (void);
-
 G_DEFINE_TYPE (RemoteDesktopSession, remote_desktop_session, session_get_type ())
 
-gboolean
-is_remote_desktop_session (Session *session)
-{
-  return G_TYPE_CHECK_INSTANCE_TYPE (session,
-                                     remote_desktop_session_get_type ());
-}
-
 gboolean
 remote_desktop_session_can_select_sources (RemoteDesktopSession *session)
 {
@@ -227,7 +218,7 @@ remote_desktop_session_new (GVariant *options,
   if (session)
     g_debug ("remote desktop session owned by '%s' created", session->sender);
 
-  return (RemoteDesktopSession *)session;
+  return REMOTE_DESKTOP_SESSION (session);
 }
 
 static void
@@ -328,7 +319,7 @@ handle_create_session (XdpDbusRemoteDesktop *object,
   request_set_impl_request (request, impl_request);
   request_export (request, g_dbus_method_invocation_get_connection (invocation));
 
-  session = (Session *)remote_desktop_session_new (arg_options, request, &error);
+  session = SESSION (remote_desktop_session_new (arg_options, request, &error));
   if (!session)
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
@@ -408,7 +399,8 @@ select_devices_done (GObject *source_object,
     }
   else if (!session->closed)
     {
-      RemoteDesktopSession *remote_desktop_session = (RemoteDesktopSession *)session;
+      RemoteDesktopSession *remote_desktop_session =
+        REMOTE_DESKTOP_SESSION (session);
 
       remote_desktop_session->devices_selected = TRUE;
     }
@@ -483,7 +475,7 @@ replace_remote_desktop_restore_token_with_data (Session *session,
                                                 GVariant **in_out_options,
                                                 GError **error)
 {
-  RemoteDesktopSession *remote_desktop_session = (RemoteDesktopSession *) session;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
   g_autoptr(GVariant) options = NULL;
   PersistMode persist_mode;
 
@@ -529,7 +521,7 @@ handle_select_devices (XdpDbusRemoteDesktop *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  remote_desktop_session = (RemoteDesktopSession *)session;
+  remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   if (!remote_desktop_session_can_select_devices (remote_desktop_session))
     {
@@ -600,7 +592,7 @@ static void
 replace_restore_remote_desktop_data_with_token (RemoteDesktopSession *remote_desktop_session,
                                                 GVariant **in_out_results)
 {
-  xdp_session_persistence_replace_restore_data_with_token ((Session *) remote_desktop_session,
+  xdp_session_persistence_replace_restore_data_with_token (SESSION (remote_desktop_session),
                                                            REMOTE_DESKTOP_TABLE,
                                                            in_out_results,
                                                            &remote_desktop_session->persist_mode,
@@ -652,7 +644,7 @@ start_done (GObject *source_object,
   REQUEST_AUTOLOCK (request);
 
   session = g_object_get_qdata (G_OBJECT (request), quark_request_session);
-  remote_desktop_session = (RemoteDesktopSession *)session;
+  remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
   SESSION_AUTOLOCK_UNREF (g_object_ref (session));
   g_object_set_qdata (G_OBJECT (request), quark_request_session, NULL);
 
@@ -735,7 +727,7 @@ handle_start (XdpDbusRemoteDesktop *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  remote_desktop_session = (RemoteDesktopSession *)session;
+  remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
   switch (remote_desktop_session->state)
     {
     case REMOTE_DESKTOP_SESSION_STATE_INIT:
@@ -799,7 +791,7 @@ static gboolean
 check_notify (Session *session,
               DeviceType device_type)
 {
-  RemoteDesktopSession *remote_desktop_session = (RemoteDesktopSession *)session;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   if (!remote_desktop_session->devices_selected || remote_desktop_session->uses_eis)
     return FALSE;
@@ -825,7 +817,7 @@ check_position (Session *session,
                 double x,
                 double y)
 {
-  RemoteDesktopSession *remote_desktop_session = (RemoteDesktopSession *)session;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
   GList *l;
 
   for (l = remote_desktop_session->streams; l; l = l->next)
@@ -1493,7 +1485,7 @@ handle_connect_to_eis (XdpDbusRemoteDesktop *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (!is_remote_desktop_session (session))
+  if (!IS_REMOTE_DESKTOP_SESSION (session))
     {
       g_dbus_method_invocation_return_error (invocation,
                                              G_DBUS_ERROR,
@@ -1502,7 +1494,7 @@ handle_connect_to_eis (XdpDbusRemoteDesktop *object,
       return G_DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-  remote_desktop_session = (RemoteDesktopSession *)session;
+  remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   if (remote_desktop_session->uses_eis)
     {
@@ -1646,7 +1638,7 @@ remote_desktop_create (GDBusConnection *connection,
 static void
 remote_desktop_session_close (Session *session)
 {
-  RemoteDesktopSession *remote_desktop_session = (RemoteDesktopSession *)session;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (session);
 
   remote_desktop_session->state = REMOTE_DESKTOP_SESSION_STATE_CLOSED;
 
@@ -1656,7 +1648,7 @@ remote_desktop_session_close (Session *session)
 static void
 remote_desktop_session_finalize (GObject *object)
 {
-  RemoteDesktopSession *remote_desktop_session = (RemoteDesktopSession *)object;
+  RemoteDesktopSession *remote_desktop_session = REMOTE_DESKTOP_SESSION (object);
 
   g_list_free_full (remote_desktop_session->streams,
                     (GDestroyNotify)screen_cast_stream_free);
diff --git a/src/remote-desktop.h b/src/remote-desktop.h
index 5e47c943f..46813a0f8 100644
--- a/src/remote-desktop.h
+++ b/src/remote-desktop.h
@@ -27,7 +27,19 @@
 
 typedef struct _RemoteDesktopSession RemoteDesktopSession;
 
-gboolean is_remote_desktop_session (Session *session);
+GType remote_desktop_session_get_type (void);
+
+G_GNUC_UNUSED static inline RemoteDesktopSession *
+REMOTE_DESKTOP_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, remote_desktop_session_get_type (), RemoteDesktopSession);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_REMOTE_DESKTOP_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, remote_desktop_session_get_type ());
+}
 
 GList * remote_desktop_session_get_streams (RemoteDesktopSession *session);
 
diff --git a/src/request.c b/src/request.c
index 447edc383..70353c636 100644
--- a/src/request.c
+++ b/src/request.c
@@ -38,7 +38,7 @@ request_on_signal_response (XdpDbusRequest *object,
                             guint arg_response,
                             GVariant *arg_results)
 {
-  Request *request = (Request *)object;
+  Request *request = REQUEST (object);
   XdpDbusRequestSkeleton *skeleton = XDP_DBUS_REQUEST_SKELETON (object);
   GList      *connections, *l;
   GVariant   *signal_variant;
@@ -67,7 +67,7 @@ static gboolean
 handle_close (XdpDbusRequest *object,
               GDBusMethodInvocation *invocation)
 {
-  Request *request = (Request *)object;
+  Request *request = REQUEST (object);
   g_autoptr(GError) error = NULL;
 
   g_debug ("Handling Close");
@@ -112,7 +112,7 @@ request_init (Request *request)
 static void
 request_finalize (GObject *object)
 {
-  Request *request = (Request *)object;
+  Request *request = REQUEST (object);
 
   G_LOCK (requests);
   g_hash_table_remove (requests, request->id);
diff --git a/src/request.h b/src/request.h
index 27a8ee3bb..20dfd9c57 100644
--- a/src/request.h
+++ b/src/request.h
@@ -57,6 +57,18 @@ struct _RequestClass
 
 GType request_get_type (void) G_GNUC_CONST;
 
+G_GNUC_UNUSED static inline Request *
+REQUEST (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, request_get_type (), Request);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_REQUEST (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, request_get_type ());
+}
+
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (Request, g_object_unref)
 
 void request_init_invocation (GDBusMethodInvocation  *invocation, XdpAppInfo *app_info);
diff --git a/src/screen-cast.c b/src/screen-cast.c
index bb115aa3c..b9f223e2e 100644
--- a/src/screen-cast.c
+++ b/src/screen-cast.c
@@ -109,11 +109,16 @@ GType screen_cast_session_get_type (void);
 
 G_DEFINE_TYPE (ScreenCastSession, screen_cast_session, session_get_type ())
 
+G_GNUC_UNUSED static inline ScreenCastSession *
+SCREEN_CAST_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, screen_cast_session_get_type (), ScreenCastSession);
+}
 
-static gboolean
-is_screen_cast_session (Session *session)
+G_GNUC_UNUSED static inline gboolean
+IS_SCREEN_CAST_SESSION (gpointer ptr)
 {
-  return G_TYPE_CHECK_INSTANCE_TYPE (session, screen_cast_session_get_type ());
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, screen_cast_session_get_type ());
 }
 
 static ScreenCastSession *
@@ -246,7 +251,7 @@ handle_create_session (XdpDbusScreenCast *object,
   request_set_impl_request (request, impl_request);
   request_export (request, g_dbus_method_invocation_get_connection (invocation));
 
-  session = (Session *)screen_cast_session_new (arg_options, request, &error);
+  session = SESSION (screen_cast_session_new (arg_options, request, &error));
   if (!session)
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
@@ -325,19 +330,19 @@ select_sources_done (GObject *source_object,
     }
   else if (!session->closed)
     {
-      if (is_screen_cast_session (session))
+      if (IS_SCREEN_CAST_SESSION (session))
         {
-          ScreenCastSession *screen_cast_session = (ScreenCastSession *)session;
+          ScreenCastSession *screen_cast_session = SCREEN_CAST_SESSION (session);
 
           g_assert_cmpint (screen_cast_session->state,
                            ==,
                            SCREEN_CAST_SESSION_STATE_SELECTING_SOURCES);
           screen_cast_session->state = SCREEN_CAST_SESSION_STATE_SOURCES_SELECTED;
         }
-      else if (is_remote_desktop_session (session))
+      else if (IS_REMOTE_DESKTOP_SESSION (session))
         {
           RemoteDesktopSession *remote_desktop_session =
-            (RemoteDesktopSession *)session;
+            REMOTE_DESKTOP_SESSION (session);
 
           remote_desktop_session_sources_selected (remote_desktop_session);
         }
@@ -444,7 +449,7 @@ replace_screen_cast_restore_token_with_data (Session *session,
   if (!g_variant_lookup (options, "persist_mode", "u", &persist_mode))
     persist_mode = PERSIST_MODE_NONE;
 
-  if (is_remote_desktop_session (session))
+  if (IS_REMOTE_DESKTOP_SESSION (session))
     {
       if (persist_mode != PERSIST_MODE_NONE ||
           xdp_variant_contains_key (options, "restore_token"))
@@ -457,9 +462,9 @@ replace_screen_cast_restore_token_with_data (Session *session,
         }
     }
 
-  if (is_screen_cast_session (session))
+  if (IS_SCREEN_CAST_SESSION (session))
     {
-      ScreenCastSession *screen_cast_session = (ScreenCastSession *)session;
+      ScreenCastSession *screen_cast_session = SCREEN_CAST_SESSION (session);
 
       screen_cast_session->persist_mode = persist_mode;
       xdp_session_persistence_replace_restore_token_with_data (session,
@@ -502,9 +507,9 @@ handle_select_sources (XdpDbusScreenCast *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (is_screen_cast_session (session))
+  if (IS_SCREEN_CAST_SESSION (session))
     {
-      ScreenCastSession *screen_cast_session = (ScreenCastSession *)session;
+      ScreenCastSession *screen_cast_session = SCREEN_CAST_SESSION (session);
 
       switch (screen_cast_session->state)
         {
@@ -532,10 +537,10 @@ handle_select_sources (XdpDbusScreenCast *object,
           return G_DBUS_METHOD_INVOCATION_HANDLED;
         }
     }
-  else if (is_remote_desktop_session (session))
+  else if (IS_REMOTE_DESKTOP_SESSION (session))
     {
       RemoteDesktopSession *remote_desktop_session =
-        (RemoteDesktopSession *)session;
+        REMOTE_DESKTOP_SESSION (session);
 
       if (!remote_desktop_session_can_select_sources (remote_desktop_session))
         {
@@ -596,9 +601,9 @@ handle_select_sources (XdpDbusScreenCast *object,
                            quark_request_session,
                            g_object_ref (session),
                            g_object_unref);
-  if (is_screen_cast_session (session))
+  if (IS_SCREEN_CAST_SESSION (session))
     {
-      ((ScreenCastSession *)session)->state =
+      SCREEN_CAST_SESSION (session)->state =
         SCREEN_CAST_SESSION_STATE_SELECTING_SOURCES;
     }
 
@@ -733,7 +738,7 @@ static void
 replace_restore_screen_cast_data_with_token (ScreenCastSession *screen_cast_session,
                                              GVariant **in_out_results)
 {
-  xdp_session_persistence_replace_restore_data_with_token ((Session *) screen_cast_session,
+  xdp_session_persistence_replace_restore_data_with_token (SESSION (screen_cast_session),
                                                            SCREEN_CAST_TABLE,
                                                            in_out_results,
                                                            &screen_cast_session->persist_mode,
@@ -792,7 +797,7 @@ start_done (GObject *source_object,
 
   should_close_session = !request->exported || response != 0;
 
-  screen_cast_session = (ScreenCastSession *)session;
+  screen_cast_session = SCREEN_CAST_SESSION (session);
 
   if (request->exported)
     {
@@ -862,7 +867,7 @@ handle_start (XdpDbusScreenCast *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  screen_cast_session = (ScreenCastSession *)session;
+  screen_cast_session = SCREEN_CAST_SESSION (session);
   switch (screen_cast_session->state)
     {
     case SCREEN_CAST_SESSION_STATE_SOURCES_SELECTED:
@@ -959,16 +964,16 @@ handle_open_pipewire_remote (XdpDbusScreenCast *object,
 
   SESSION_AUTOLOCK_UNREF (session);
 
-  if (is_screen_cast_session (session))
+  if (IS_SCREEN_CAST_SESSION (session))
     {
-      ScreenCastSession *screen_cast_session = (ScreenCastSession *)session;
+      ScreenCastSession *screen_cast_session = SCREEN_CAST_SESSION (session);
 
       streams = screen_cast_session->streams;
     }
-  else if (is_remote_desktop_session (session))
+  else if (IS_REMOTE_DESKTOP_SESSION (session))
     {
       RemoteDesktopSession *remote_desktop_session =
-        (RemoteDesktopSession *)session;
+        REMOTE_DESKTOP_SESSION (session);
 
       streams = remote_desktop_session_get_streams (remote_desktop_session);
     }
@@ -1121,7 +1126,7 @@ screen_cast_create (GDBusConnection *connection,
 static void
 screen_cast_session_close (Session *session)
 {
-  ScreenCastSession *screen_cast_session = (ScreenCastSession *)session;
+  ScreenCastSession *screen_cast_session = SCREEN_CAST_SESSION (session);
 
   screen_cast_session->state = SCREEN_CAST_SESSION_STATE_CLOSED;
 
@@ -1137,7 +1142,7 @@ screen_cast_session_close (Session *session)
 static void
 screen_cast_session_finalize (GObject *object)
 {
-  ScreenCastSession *screen_cast_session = (ScreenCastSession *)object;
+  ScreenCastSession *screen_cast_session = SCREEN_CAST_SESSION (object);
 
   g_clear_pointer (&screen_cast_session->restore_token, g_free);
   g_clear_pointer (&screen_cast_session->restore_data, g_variant_unref);
diff --git a/src/screenshot.c b/src/screenshot.c
index 1626b0c64..974a33d68 100644
--- a/src/screenshot.c
+++ b/src/screenshot.c
@@ -191,7 +191,7 @@ handle_screenshot_in_thread_func (GTask *task,
                                   gpointer task_data,
                                   GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   g_autoptr(GError) error = NULL;
   g_autoptr(XdpDbusImplRequest) impl_request = NULL;
   GVariantBuilder opt_builder;
diff --git a/src/session.c b/src/session.c
index ad8d922c0..607256591 100644
--- a/src/session.c
+++ b/src/session.c
@@ -217,7 +217,7 @@ static gboolean
 handle_close (XdpDbusSession *object,
               GDBusMethodInvocation *invocation)
 {
-  Session *session = (Session *)object;
+  Session *session = SESSION (object);
 
   SESSION_AUTOLOCK_UNREF (g_object_ref (session));
 
@@ -283,7 +283,7 @@ close_sessions_for_sender (const char *sender)
 static void
 on_closed (XdpDbusImplSession *object, GObject *data)
 {
-  Session *session = (Session *)data;
+  Session *session = SESSION (data);
 
   SESSION_AUTOLOCK_UNREF (g_object_ref (session));
 
@@ -316,7 +316,7 @@ session_initable_init (GInitable *initable,
                        GCancellable *cancellable,
                        GError **error)
 {
-  Session *session = (Session *)initable;
+  Session *session = SESSION (initable);
   g_autofree char *sender_escaped = NULL;
   g_autofree char *id = NULL;
   g_autoptr(XdpDbusImplSession) impl_session = NULL;
@@ -377,7 +377,7 @@ session_set_property (GObject *object,
                       const GValue *value,
                       GParamSpec *pspec)
 {
-  Session *session = (Session *)object;
+  Session *session = SESSION (object);
 
   switch (prop_id)
     {
@@ -416,7 +416,7 @@ session_get_property (GObject *object,
                       GValue *value,
                       GParamSpec *pspec)
 {
-  Session *session = (Session *)object;
+  Session *session = SESSION (object);
 
   switch (prop_id)
     {
@@ -452,7 +452,7 @@ session_get_property (GObject *object,
 static void
 session_finalize (GObject *object)
 {
-  Session *session = (Session *)object;
+  Session *session = SESSION (object);
 
   g_assert (!session->id || !g_hash_table_lookup (sessions, session->id));
 
diff --git a/src/session.h b/src/session.h
index f12ca5a4a..283543ae6 100644
--- a/src/session.h
+++ b/src/session.h
@@ -58,6 +58,18 @@ struct _SessionClass
 
 GType session_get_type (void);
 
+G_GNUC_UNUSED static inline Session *
+SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_CAST (ptr, session_get_type (), Session);
+}
+
+G_GNUC_UNUSED static inline gboolean
+IS_SESSION (gpointer ptr)
+{
+  return G_TYPE_CHECK_INSTANCE_TYPE (ptr, session_get_type ());
+}
+
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (Session, g_object_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (XdpDbusImplSession, g_object_unref)
 
diff --git a/src/wallpaper.c b/src/wallpaper.c
index 5832699f2..66c1f949e 100644
--- a/src/wallpaper.c
+++ b/src/wallpaper.c
@@ -125,7 +125,7 @@ handle_set_wallpaper_in_thread_func (GTask *task,
                                      gpointer task_data,
                                      GCancellable *cancellable)
 {
-  Request *request = (Request *)task_data;
+  Request *request = REQUEST (task_data);
   const char *parent_window;
   const char *id = xdp_app_info_get_id (request->app_info);
   g_autoptr(GError) error = NULL;