diff --git a/src/backend/backend.h b/src/backend/backend.h
index bfeed3d..3383be5 100644
--- a/src/backend/backend.h
+++ b/src/backend/backend.h
@@ -3,6 +3,8 @@
 
 #pragma once
 
+#include <stdbool.h>
+
 #include "region.h"
 #include "compiler.h"
 
diff --git a/src/backend/gl/gl_common.h b/src/backend/gl/gl_common.h
index 9aa423f..c07376f 100644
--- a/src/backend/gl/gl_common.h
+++ b/src/backend/gl/gl_common.h
@@ -1,9 +1,11 @@
 #pragma once
+#include <stdbool.h>
 #include <string.h>
 #include <GL/gl.h>
 #include <GL/glext.h>
 
 #include "common.h"
+#include "region.h"
 #include "log.h"
 
 // Program and uniforms for window shader
@@ -122,7 +124,7 @@ static inline bool gl_has_extension(const char *ext) {
 	GLint nexts = 0;
 	glGetIntegerv(GL_NUM_EXTENSIONS, &nexts);
 	if (!nexts) {
-		log_error("Failed get GL extension list.");
+		log_error("Failed to get GL extension list.");
 		return false;
 	}
 
diff --git a/src/backend/gl/glx.c b/src/backend/gl/glx.c
index 6bba38b..a298f52 100644
--- a/src/backend/gl/glx.c
+++ b/src/backend/gl/glx.c
@@ -9,24 +9,24 @@
  *
  */
 
-#include <assert.h>
 #include <GL/glx.h>
-#include <stdbool.h>
-#include <xcb/xcb.h>
-#include <xcb/composite.h>
-#include <string.h>
-#include <stdlib.h>
+#include <assert.h>
 #include <pixman.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <xcb/composite.h>
+#include <xcb/xcb.h>
 
 #include "backend/backend.h"
 #include "backend/gl/gl_common.h"
 #include "common.h"
 #include "compiler.h"
+#include "config.h"
 #include "log.h"
 #include "region.h"
 #include "utils.h"
 #include "win.h"
-#include "config.h"
 
 /// @brief Wrapper of a GLX FBConfig.
 typedef struct glx_fbconfig {
diff --git a/src/compton.c b/src/compton.c
index 0174908..7ffb7f3 100644
--- a/src/compton.c
+++ b/src/compton.c
@@ -28,6 +28,7 @@
 
 #include <ev.h>
 
+#include "kernel.h"
 #include "common.h"
 #include "compiler.h"
 #include "compton.h"