diff --git a/src/core/layer.c b/src/core/layer.c
index 56f706e..f953bc4 100644
--- a/src/core/layer.c
+++ b/src/core/layer.c
@@ -5,6 +5,7 @@
 #include "base/array.h"
 #include "base/memory.h"
 #include "core/types.h"
+#include "core/window.h"
 
 void layer_stack_cleanup(layer_stack_t *layer) {
   p_delete(&layer->order);
@@ -86,3 +87,17 @@ bool layer_stack_lower(layer_stack_t *layer, window_id_t window) {
 
   return true;
 }
+
+layer_type_t layer_classify(const window_props_t *props) {
+  for (size_t i = 0; i < props->type_count; ++i) {
+    window_type_t type = props->types[i];
+    if (type == ZDWM_WINDOW_TYPE_NOTIFICATION) return ZDWM_WINDOW_LAYER_OVERLAY;
+  }
+
+  for (size_t i = 0; i < props->state_count; ++i) {
+    window_state_t state = props->states[i];
+    if (state == ZDWM_WINDOW_STATE_ABOVE) return ZDWM_WINDOW_LAYER_TOP;
+  }
+
+  return ZDWM_WINDOW_LAYER_NORMAL;
+}
diff --git a/src/core/policy.c b/src/core/policy.c
new file mode 100644
index 0000000..48fa546
--- /dev/null
+++ b/src/core/policy.c
@@ -0,0 +1,10 @@
+#include "core/policy.h"
+
+#include "base/macros.h"
+#include "core/state.h"
+
+layer_type_t policy_adjust_window_layer_from_transient(
+  const state_t *state, window_id_t transient_for, layer_type_t base_layer) {
+  const window_t *window = state_window_get(state, transient_for);
+  return MAX(window->layer, base_layer);
+}