diff --git a/output.c b/output.c
index 0577c0d..e937bc7 100644
--- a/output.c
+++ b/output.c
@@ -1,7 +1,7 @@
 /*
  * Cage: A Wayland kiosk.
  *
- * Copyright (C) 2018-2020 Jente Hidskes
+ * Copyright (C) 2018-2021 Jente Hidskes
  * Copyright (C) 2019 The Sway authors
  *
  * See the LICENSE file accompanying this file.
@@ -230,6 +230,10 @@ handle_new_output(struct wl_listener *listener, void *data)
 		}
 	}
 
+	for (size_t i = 0; i < sizeof(output->layers) / sizeof(output->layers[0]); i++) {
+		wl_list_init(&output->layers[i]);
+	}
+
 	if (!wlr_xcursor_manager_load(server->seat->xcursor_manager, wlr_output->scale)) {
 		wlr_log(WLR_ERROR, "Cannot load XCursor theme for output '%s' with scale %f", wlr_output->name,
 			wlr_output->scale);
diff --git a/output.h b/output.h
index ced06f6..ffd349c 100644
--- a/output.h
+++ b/output.h
@@ -8,6 +8,14 @@
 #include "server.h"
 #include "view.h"
 
+/* There exist currently four layers:
+ * - ZWLR_LAYER_SHELL_V1_LAYER_BACKGROUND
+ * - ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM
+ * - ZWLR_LAYER_SHELL_V1_LAYER_TOP
+ * - ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY
+ */
+#define NUM_LAYERS 4
+
 struct cg_output {
 	struct cg_server *server;
 	struct wlr_output *wlr_output;
@@ -19,6 +27,7 @@ struct cg_output {
 	struct wl_listener frame;
 
 	struct wl_list link; // cg_server::outputs
+	struct wl_list layers[NUM_LAYERS]; // cg_layer_surface::link
 };
 
 void handle_new_output(struct wl_listener *listener, void *data);