diff --git a/include/picom/backend.h b/include/picom/backend.h
index f8a60c98..ab0757a7 100644
--- a/include/picom/backend.h
+++ b/include/picom/backend.h
@@ -172,49 +172,6 @@ enum backend_image_capability {
 	BACKEND_IMAGE_CAP_DST = 1 << 1,
 };
 
-enum backend_command_op {
-	BACKEND_COMMAND_INVALID = -1,
-	BACKEND_COMMAND_BLIT,
-	BACKEND_COMMAND_BLUR,
-	BACKEND_COMMAND_COPY_AREA,
-};
-
-/// Symbolic references used as render command source images. The actual `image_handle`
-/// will later be filled in by the renderer using this symbolic reference.
-enum backend_command_source {
-	BACKEND_COMMAND_SOURCE_WINDOW,
-	BACKEND_COMMAND_SOURCE_WINDOW_SAVED,
-	BACKEND_COMMAND_SOURCE_SHADOW,
-	BACKEND_COMMAND_SOURCE_BACKGROUND,
-};
-
-// TODO(yshui) might need better names
-
-struct backend_command {
-	enum backend_command_op op;
-	ivec2 origin;
-	enum backend_command_source source;
-	union {
-		struct {
-			struct backend_blit_args blit;
-			/// Region of the screen that will be covered by this blit
-			/// operations, in screen coordinates.
-			region_t opaque_region;
-		};
-		struct {
-			image_handle source_image;
-			const region_t *region;
-		} copy_area;
-		struct backend_blur_args blur;
-	};
-	/// Source mask for the operation.
-	/// If the `source_mask` of the operation's argument points to this, a mask image
-	/// will be created for the operation for the renderer.
-	struct backend_mask_image source_mask;
-	/// Target mask for the operation.
-	region_t target_mask;
-};
-
 enum backend_quirk {
 	/// Backend cannot do blur quickly. The compositor will avoid using blur to create
 	/// shadows on this backend
diff --git a/src/backend/backend.h b/src/backend/backend.h
index 32c037c9..d0f4cfdc 100644
--- a/src/backend/backend.h
+++ b/src/backend/backend.h
@@ -9,6 +9,49 @@
 
 #include "log.h"
 
+enum backend_command_op {
+	BACKEND_COMMAND_INVALID = -1,
+	BACKEND_COMMAND_BLIT,
+	BACKEND_COMMAND_BLUR,
+	BACKEND_COMMAND_COPY_AREA,
+};
+
+/// Symbolic references used as render command source images. The actual `image_handle`
+/// will later be filled in by the renderer using this symbolic reference.
+enum backend_command_source {
+	BACKEND_COMMAND_SOURCE_WINDOW,
+	BACKEND_COMMAND_SOURCE_WINDOW_SAVED,
+	BACKEND_COMMAND_SOURCE_SHADOW,
+	BACKEND_COMMAND_SOURCE_BACKGROUND,
+};
+
+// TODO(yshui) might need better names
+
+struct backend_command {
+	enum backend_command_op op;
+	ivec2 origin;
+	enum backend_command_source source;
+	union {
+		struct {
+			struct backend_blit_args blit;
+			/// Region of the screen that will be covered by this blit
+			/// operations, in screen coordinates.
+			region_t opaque_region;
+		};
+		struct {
+			image_handle source_image;
+			const region_t *region;
+		} copy_area;
+		struct backend_blur_args blur;
+	};
+	/// Source mask for the operation.
+	/// If the `source_mask` of the operation's argument points to this, a mask image
+	/// will be created for the operation for the renderer.
+	struct backend_mask_image source_mask;
+	/// Target mask for the operation.
+	region_t target_mask;
+};
+
 bool backend_execute(struct backend_base *backend, image_handle target, unsigned ncmds,
                      const struct backend_command cmds[ncmds]);
 
diff --git a/src/renderer/command_builder.c b/src/renderer/command_builder.c
index 3f26a1fd..50f3312e 100644
--- a/src/renderer/command_builder.c
+++ b/src/renderer/command_builder.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: MPL-2.0
 // Copyright (c) Yuxuan Shui <yshuiv7@gmail.com>
 
+#include "backend/backend.h"
 #include "common.h"
 #include "layout.h"
 #include "utils/dynarr.h"
diff --git a/src/renderer/damage.c b/src/renderer/damage.c
index 5778e717..6eb155f8 100644
--- a/src/renderer/damage.c
+++ b/src/renderer/damage.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: MPL-2.0
 // Copyright (c) Yuxuan Shui <yshuiv7@gmail.com>
 
+#include "backend/backend.h"
 #include "layout.h"
 #include "region.h"
 #include "utils/dynarr.h"