diff --git a/i3-config-wizard/main.c b/i3-config-wizard/main.c
index f999de308..61db75ecd 100644
--- a/i3-config-wizard/main.c
+++ b/i3-config-wizard/main.c
@@ -23,37 +23,36 @@
 #define _WITH_GETLINE
 #endif
 
-#include <stdio.h>
-#include <sys/types.h>
-#include <stdlib.h>
-#include <stdbool.h>
-#include <unistd.h>
-#include <string.h>
+#include <assert.h>
 #include <ctype.h>
-#include <errno.h>
 #include <err.h>
-#include <stdint.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
+#include <glob.h>
 #include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
-#include <fcntl.h>
-#include <glob.h>
-#include <assert.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
 #include <xcb/xcb_event.h>
 #include <xcb/xcb_keysyms.h>
-
-#include <xkbcommon/xkbcommon.h>
 #include <xkbcommon/xkbcommon-x11.h>
+#include <xkbcommon/xkbcommon.h>
 
 #define SN_API_NOT_YET_FROZEN 1
 #include <libsn/sn-launchee.h>
 
+#include <X11/XKBlib.h>
 #include <X11/Xlib.h>
 #include <X11/keysym.h>
-#include <X11/XKBlib.h>
 
 /* We need SYSCONFDIR for the path to the keycode config template, so raise an
  * error if it’s not defined for whatever reason */
diff --git a/i3-dump-log/main.c b/i3-dump-log/main.c
index ba60d396e..e55f1d3c9 100644
--- a/i3-dump-log/main.c
+++ b/i3-dump-log/main.c
@@ -9,27 +9,27 @@
  */
 #include <config.h>
 
-#include <stdio.h>
-#include <stdbool.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <string.h>
-#include <errno.h>
+#include "libi3.h"
+#include "shmlog.h"
+
 #include <err.h>
-#include <stdint.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
+#include <i3/ipc.h>
 #include <limits.h>
-#include <fcntl.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/mman.h>
+#include <sys/socket.h>
 #include <sys/stat.h>
-#include <signal.h>
-
-#include "libi3.h"
-#include "shmlog.h"
-#include <i3/ipc.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
 
 #if !defined(__OpenBSD__)
 static uint32_t offset_next_write;
diff --git a/i3-input/keysym2ucs.c b/i3-input/keysym2ucs.c
index 52bdc0444..80375099c 100644
--- a/i3-input/keysym2ucs.c
+++ b/i3-input/keysym2ucs.c
@@ -31,9 +31,10 @@
  * This software is in the public domain. Share and enjoy!
  */
 
-#include <xcb/xcb.h>
 #include "keysym2ucs.h"
 
+#include <xcb/xcb.h>
+
 struct codepair {
     unsigned short keysym;
     unsigned short ucs;
diff --git a/i3-input/main.c b/i3-input/main.c
index e495fe10a..1a4cbc7d1 100644
--- a/i3-input/main.c
+++ b/i3-input/main.c
@@ -8,17 +8,17 @@
  *                  to i3.
  *
  */
-#include <stdio.h>
-#include <sys/types.h>
-#include <stdlib.h>
-#include <stdbool.h>
-#include <unistd.h>
-#include <string.h>
-#include <errno.h>
 #include <err.h>
-#include <stdint.h>
+#include <errno.h>
 #include <getopt.h>
 #include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
@@ -26,14 +26,12 @@
 #include <xcb/xcb_keysyms.h>
 
 xcb_visualtype_t *visual_type = NULL;
+#include "i3-input.h"
+#include "keysym2ucs.h"
 #include "libi3.h"
 
 #include <X11/keysym.h>
 
-#include "keysym2ucs.h"
-
-#include "i3-input.h"
-
 #define MAX_WIDTH logical_px(500)
 #define BORDER logical_px(2)
 #define PADDING logical_px(2)
diff --git a/i3-msg/main.c b/i3-msg/main.c
index 3a8974161..dd72bd561 100644
--- a/i3-msg/main.c
+++ b/i3-msg/main.c
@@ -16,27 +16,25 @@
  */
 #include "libi3.h"
 
-#include <stdio.h>
+#include <err.h>
+#include <errno.h>
+#include <getopt.h>
+#include <i3/ipc.h>
+#include <limits.h>
 #include <stdbool.h>
-#include <sys/types.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/socket.h>
+#include <sys/types.h>
 #include <sys/un.h>
-#include <stdlib.h>
 #include <unistd.h>
-#include <string.h>
-#include <errno.h>
-#include <err.h>
-#include <stdint.h>
-#include <getopt.h>
-#include <limits.h>
-
-#include <yajl/yajl_parse.h>
-#include <yajl/yajl_version.h>
 
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
-
-#include <i3/ipc.h>
+#include <yajl/yajl_parse.h>
+#include <yajl/yajl_version.h>
 
 /*
  * Having verboselog() and errorlog() is necessary when using libi3.
diff --git a/i3-nagbar/main.c b/i3-nagbar/main.c
index e59f5a6a3..5558865b3 100644
--- a/i3-nagbar/main.c
+++ b/i3-nagbar/main.c
@@ -8,36 +8,36 @@
  * when the user has an error in their configuration file.
  *
  */
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/wait.h>
-#include <stdlib.h>
-#include <stdbool.h>
-#include <unistd.h>
-#include <string.h>
-#include <errno.h>
 #include <err.h>
-#include <stdint.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
 #include <limits.h>
-#include <fcntl.h>
 #include <paths.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
 
+#include <xcb/randr.h>
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
-#include <xcb/xcb_event.h>
-#include <xcb/randr.h>
 #include <xcb/xcb_cursor.h>
+#include <xcb/xcb_event.h>
 
 xcb_visualtype_t *visual_type = NULL;
 #include "libi3.h"
 
 #define SN_API_NOT_YET_FROZEN 1
-#include <libsn/sn-launchee.h>
-
 #include "i3-nagbar.h"
 
+#include <libsn/sn-launchee.h>
+
 #define MSG_PADDING logical_px(8)
 #define BTN_PADDING logical_px(3)
 #define BTN_BORDER logical_px(3)
diff --git a/i3bar/src/child.c b/i3bar/src/child.c
index e56145fac..4723dbc57 100644
--- a/i3bar/src/child.c
+++ b/i3bar/src/child.c
@@ -10,25 +10,25 @@
 #include "common.h"
 #include "yajl_utils.h"
 
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/wait.h>
+#include <err.h>
+#include <errno.h>
+#include <ev.h>
+#include <fcntl.h>
+#include <paths.h>
 #include <signal.h>
-#include <stdio.h>
 #include <stdarg.h>
-#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <errno.h>
-#include <err.h>
-#include <ev.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <xcb/xcb_keysyms.h>
 #include <yajl/yajl_common.h>
+#include <yajl/yajl_gen.h>
 #include <yajl/yajl_parse.h>
 #include <yajl/yajl_version.h>
-#include <yajl/yajl_gen.h>
-#include <paths.h>
-
-#include <xcb/xcb_keysyms.h>
 
 /* Global variables for child_*() */
 i3bar_child child;
diff --git a/i3bar/src/config.c b/i3bar/src/config.c
index 29b0908b0..48f49b898 100644
--- a/i3bar/src/config.c
+++ b/i3bar/src/config.c
@@ -9,15 +9,15 @@
  */
 #include "common.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <stdio.h>
 #include <errno.h>
 #include <i3/ipc.h>
-#include <yajl/yajl_parse.h>
-#include <yajl/yajl_version.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include <X11/Xlib.h>
+#include <yajl/yajl_parse.h>
+#include <yajl/yajl_version.h>
 
 config_t config;
 static char *cur_key;
diff --git a/i3bar/src/ipc.c b/i3bar/src/ipc.c
index 37bdbac2b..d2edfe787 100644
--- a/i3bar/src/ipc.c
+++ b/i3bar/src/ipc.c
@@ -9,16 +9,16 @@
  */
 #include "common.h"
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
+#include <errno.h>
+#include <ev.h>
+#include <i3/ipc.h>
 #include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <errno.h>
 #include <sys/socket.h>
 #include <sys/un.h>
-#include <i3/ipc.h>
-#include <ev.h>
+#include <unistd.h>
 #ifdef I3_ASAN_ENABLED
 #include <sanitizer/lsan_interface.h>
 #endif
diff --git a/i3bar/src/main.c b/i3bar/src/main.c
index 65cb00ff5..b3e23cda7 100644
--- a/i3bar/src/main.c
+++ b/i3bar/src/main.c
@@ -7,15 +7,15 @@
  */
 #include "common.h"
 
-#include <stdio.h>
-#include <i3/ipc.h>
-#include <string.h>
-#include <unistd.h>
-#include <stdlib.h>
 #include <errno.h>
 #include <ev.h>
 #include <getopt.h>
 #include <glob.h>
+#include <i3/ipc.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 struct ev_loop *main_loop;
 
diff --git a/i3bar/src/mode.c b/i3bar/src/mode.c
index 97087ce09..1f0e22fa8 100644
--- a/i3bar/src/mode.c
+++ b/i3bar/src/mode.c
@@ -9,10 +9,11 @@
  */
 #include "common.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <stdio.h>
 #include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
 #include <yajl/yajl_parse.h>
 #include <yajl/yajl_version.h>
 
diff --git a/i3bar/src/outputs.c b/i3bar/src/outputs.c
index 6ebb7cc6b..f1dab9f16 100644
--- a/i3bar/src/outputs.c
+++ b/i3bar/src/outputs.c
@@ -9,11 +9,12 @@
  */
 #include "common.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <stdio.h>
 #include <errno.h>
 #include <i3/ipc.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
 #include <yajl/yajl_parse.h>
 #include <yajl/yajl_version.h>
 
diff --git a/i3bar/src/parse_json_header.c b/i3bar/src/parse_json_header.c
index 3d4c2a67f..cd857d917 100644
--- a/i3bar/src/parse_json_header.c
+++ b/i3bar/src/parse_json_header.c
@@ -10,19 +10,20 @@
  */
 #include "common.h"
 
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <signal.h>
-#include <stdio.h>
-#include <fcntl.h>
-#include <string.h>
-#include <errno.h>
 #include <err.h>
+#include <errno.h>
 #include <ev.h>
+#include <fcntl.h>
+#include <signal.h>
 #include <stdbool.h>
 #include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
 #include <yajl/yajl_common.h>
 #include <yajl/yajl_parse.h>
 #include <yajl/yajl_version.h>
diff --git a/i3bar/src/workspaces.c b/i3bar/src/workspaces.c
index 68686611a..51b863ca4 100644
--- a/i3bar/src/workspaces.c
+++ b/i3bar/src/workspaces.c
@@ -9,10 +9,11 @@
  */
 #include "common.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <stdio.h>
 #include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
 #include <yajl/yajl_parse.h>
 #include <yajl/yajl_version.h>
 
diff --git a/i3bar/src/xcb.c b/i3bar/src/xcb.c
index ecb41a603..0b0e23b09 100644
--- a/i3bar/src/xcb.c
+++ b/i3bar/src/xcb.c
@@ -9,26 +9,25 @@
  */
 #include "common.h"
 
-#include <xcb/xcb.h>
-#include <xcb/xkb.h>
-#include <xcb/xproto.h>
-#include <xcb/xcb_aux.h>
-#include <xcb/xcb_cursor.h>
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
+#include <err.h>
+#include <errno.h>
+#include <ev.h>
 #include <fcntl.h>
-#include <string.h>
 #include <i3/ipc.h>
-#include <ev.h>
-#include <errno.h>
 #include <limits.h>
-#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
-#include <X11/Xlib.h>
 #include <X11/XKBlib.h>
+#include <X11/Xlib.h>
 #include <X11/extensions/XKB.h>
+#include <xcb/xcb.h>
+#include <xcb/xcb_aux.h>
+#include <xcb/xcb_cursor.h>
+#include <xcb/xkb.h>
+#include <xcb/xproto.h>
 
 #ifdef I3_ASAN_ENABLED
 #include <sanitizer/lsan_interface.h>
diff --git a/libi3/dpi.c b/libi3/dpi.c
index d15e35be7..dec38bc86 100644
--- a/libi3/dpi.c
+++ b/libi3/dpi.c
@@ -9,6 +9,7 @@
 
 #include <math.h>
 #include <stdlib.h>
+
 #include <xcb/xcb_xrm.h>
 
 static long dpi;
diff --git a/libi3/draw_util.c b/libi3/draw_util.c
index 092ac967b..710c536a3 100644
--- a/libi3/draw_util.c
+++ b/libi3/draw_util.c
@@ -8,12 +8,13 @@
  */
 #include "libi3.h"
 
-#include <stdlib.h>
+#include <cairo/cairo-xcb.h>
 #include <err.h>
+#include <stdlib.h>
 #include <string.h>
+
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
-#include <cairo/cairo-xcb.h>
 
 /* The default visual_type to use if none is specified when creating the surface. Must be defined globally. */
 extern xcb_visualtype_t *visual_type;
diff --git a/libi3/fake_configure_notify.c b/libi3/fake_configure_notify.c
index 145f45122..e79a748b2 100644
--- a/libi3/fake_configure_notify.c
+++ b/libi3/fake_configure_notify.c
@@ -7,8 +7,8 @@
  */
 #include "libi3.h"
 
-#include <stdlib.h>
 #include <stdbool.h>
+#include <stdlib.h>
 
 #include <xcb/xcb.h>
 #include <xcb/xproto.h>
diff --git a/libi3/font.c b/libi3/font.c
index 7b10edf02..e89455240 100644
--- a/libi3/font.c
+++ b/libi3/font.c
@@ -8,14 +8,13 @@
 #include "libi3.h"
 
 #include <assert.h>
+#include <cairo/cairo-xcb.h>
+#include <err.h>
+#include <pango/pangocairo.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
-#include <stdbool.h>
-#include <err.h>
-
-#include <cairo/cairo-xcb.h>
-#include <pango/pangocairo.h>
 
 static const i3Font *savedFont = NULL;
 
diff --git a/libi3/format_placeholders.c b/libi3/format_placeholders.c
index 770e383d7..99fa3055a 100644
--- a/libi3/format_placeholders.c
+++ b/libi3/format_placeholders.c
@@ -7,8 +7,8 @@
  */
 #include "libi3.h"
 
-#include <stdlib.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
 
 #ifndef CS_STARTS_WITH
diff --git a/libi3/g_utf8_make_valid.c b/libi3/g_utf8_make_valid.c
index b15873b37..71beafd30 100644
--- a/libi3/g_utf8_make_valid.c
+++ b/libi3/g_utf8_make_valid.c
@@ -19,8 +19,8 @@
 
 #include "libi3.h"
 
-#include <string.h>
 #include <glib.h>
+#include <string.h>
 
 /* Copied from:
  * https://gitlab.gnome.org/GNOME/glib/blob/f928dfdf57bf92c883b53b16d7a9d49add504f52/glib/gutf8.c#L1752-1815 */
diff --git a/libi3/get_colorpixel.c b/libi3/get_colorpixel.c
index 459310516..b60ffbac3 100644
--- a/libi3/get_colorpixel.c
+++ b/libi3/get_colorpixel.c
@@ -6,12 +6,11 @@
  *
  */
 #include "libi3.h"
+#include "queue.h"
 
-#include <stdlib.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
-
-#include "queue.h"
 struct Colorpixel {
     char hex[8];
     uint32_t pixel;
diff --git a/libi3/get_exe_path.c b/libi3/get_exe_path.c
index 430fb2e07..762b4965e 100644
--- a/libi3/get_exe_path.c
+++ b/libi3/get_exe_path.c
@@ -7,12 +7,12 @@
  */
 #include "libi3.h"
 
-#include <unistd.h>
-#include <string.h>
-#include <stdio.h>
+#include <errno.h>
 #include <limits.h>
+#include <stdio.h>
 #include <stdlib.h>
-#include <errno.h>
+#include <string.h>
+#include <unistd.h>
 
 /*
  * This function returns the absolute path to the executable it is running in.
diff --git a/libi3/get_mod_mask.c b/libi3/get_mod_mask.c
index 98031d4ce..92af456df 100644
--- a/libi3/get_mod_mask.c
+++ b/libi3/get_mod_mask.c
@@ -9,6 +9,7 @@
 
 #include <stdint.h>
 #include <stdlib.h>
+
 #include <xcb/xcb.h>
 #include <xcb/xcb_keysyms.h>
 
diff --git a/libi3/get_process_filename.c b/libi3/get_process_filename.c
index 7e2ecbd24..6e155ea8a 100644
--- a/libi3/get_process_filename.c
+++ b/libi3/get_process_filename.c
@@ -8,16 +8,15 @@
 #include "libi3.h"
 
 #include <assert.h>
+#include <err.h>
+#include <pwd.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
-#include <stdbool.h>
-#include <err.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <pwd.h>
 #include <unistd.h>
-#include <err.h>
 
 /*
  * Returns the name of a temporary file with the specified prefix.
diff --git a/libi3/ipc_connect.c b/libi3/ipc_connect.c
index f659a1a47..614ccdf38 100644
--- a/libi3/ipc_connect.c
+++ b/libi3/ipc_connect.c
@@ -7,14 +7,14 @@
  */
 #include "libi3.h"
 
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <string.h>
 #include <err.h>
+#include <fcntl.h>
 #include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/un.h>
 #include <unistd.h>
-#include <fcntl.h>
 
 /*
  * Connects to the i3 IPC socket and returns the file descriptor for the
diff --git a/libi3/ipc_recv_message.c b/libi3/ipc_recv_message.c
index 84da5aa36..6364b16d0 100644
--- a/libi3/ipc_recv_message.c
+++ b/libi3/ipc_recv_message.c
@@ -7,15 +7,14 @@
  */
 #include "libi3.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <unistd.h>
 #include <errno.h>
-#include <inttypes.h>
-
 #include <i3/ipc.h>
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 /*
  * Reads a message from the given socket file descriptor and stores its length
diff --git a/libi3/ipc_send_message.c b/libi3/ipc_send_message.c
index c2cc0127d..106db348e 100644
--- a/libi3/ipc_send_message.c
+++ b/libi3/ipc_send_message.c
@@ -7,14 +7,13 @@
  */
 #include "libi3.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <stdint.h>
 #include <err.h>
 #include <errno.h>
-
 #include <i3/ipc.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 /*
  * Formats a message (payload) of the given size and type and sends it to i3 via
diff --git a/libi3/is_debug_build.c b/libi3/is_debug_build.c
index 52187bdae..afd06237c 100644
--- a/libi3/is_debug_build.c
+++ b/libi3/is_debug_build.c
@@ -7,8 +7,8 @@
  */
 #include "libi3.h"
 
-#include <string.h>
 #include <stdbool.h>
+#include <string.h>
 
 /*
  * Returns true if this version of i3 is a debug build (anything which is not a
diff --git a/libi3/root_atom_contents.c b/libi3/root_atom_contents.c
index d6394d4bf..134733a2d 100644
--- a/libi3/root_atom_contents.c
+++ b/libi3/root_atom_contents.c
@@ -7,12 +7,12 @@
  */
 #include "libi3.h"
 
-#include <stdio.h>
-#include <string.h>
-#include <stdbool.h>
 #include <limits.h>
-#include <stdlib.h>
 #include <math.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
diff --git a/libi3/safewrappers.c b/libi3/safewrappers.c
index fdea636ee..d4225ffe0 100644
--- a/libi3/safewrappers.c
+++ b/libi3/safewrappers.c
@@ -7,13 +7,13 @@
  */
 #include "libi3.h"
 
-#include <string.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <stdio.h>
 #include <err.h>
 #include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 /*
  * The s* functions (safe) are wrappers around malloc, strdup, …, which exits if one of
diff --git a/libi3/string.c b/libi3/string.c
index 9efa36903..da18c550b 100644
--- a/libi3/string.c
+++ b/libi3/string.c
@@ -11,11 +11,10 @@
  */
 #include "libi3.h"
 
+#include <glib.h>
 #include <stdlib.h>
 #include <string.h>
 
-#include <glib.h>
-
 struct _i3String {
     char *utf8;
     xcb_char2b_t *ucs2;
diff --git a/libi3/strndup.c b/libi3/strndup.c
index e215a76fd..533958d2e 100644
--- a/libi3/strndup.c
+++ b/libi3/strndup.c
@@ -7,8 +7,8 @@
  */
 #include "libi3.h"
 
-#include <sys/types.h>
 #include <string.h>
+#include <sys/types.h>
 
 #ifndef HAVE_strndup
 /*
diff --git a/src/bindings.c b/src/bindings.c
index 03dc23065..74d70c5c0 100644
--- a/src/bindings.c
+++ b/src/bindings.c
@@ -8,8 +8,8 @@
  */
 #include "all.h"
 
-#include <xkbcommon/xkbcommon.h>
 #include <xkbcommon/xkbcommon-x11.h>
+#include <xkbcommon/xkbcommon.h>
 
 static struct xkb_context *xkb_context;
 static struct xkb_keymap *xkb_keymap;
diff --git a/src/click.c b/src/click.c
index 12e391b53..7cd32e111 100644
--- a/src/click.c
+++ b/src/click.c
@@ -9,12 +9,11 @@
  */
 #include "all.h"
 
-#include <time.h>
 #include <math.h>
-
-#include <xcb/xcb_icccm.h>
+#include <time.h>
 
 #include <X11/XKBlib.h>
+#include <xcb/xcb_icccm.h>
 
 typedef enum { CLICK_BORDER = 0,
                CLICK_DECORATION = 1,
diff --git a/src/commands.c b/src/commands.c
index d20246522..c96651d09 100644
--- a/src/commands.c
+++ b/src/commands.c
@@ -8,14 +8,13 @@
  *
  */
 #include "all.h"
+#include "shmlog.h"
 
-#include <stdint.h>
+#include <fcntl.h>
 #include <float.h>
 #include <stdarg.h>
+#include <stdint.h>
 #include <unistd.h>
-#include <fcntl.h>
-
-#include "shmlog.h"
 
 // Macros to make the YAJL API a bit easier to use.
 #define y(x, ...) (cmd_output->json_gen != NULL ? yajl_gen_##x(cmd_output->json_gen, ##__VA_ARGS__) : 0)
diff --git a/src/commands_parser.c b/src/commands_parser.c
index 2fd763095..35005d0e1 100644
--- a/src/commands_parser.c
+++ b/src/commands_parser.c
@@ -25,12 +25,12 @@
  */
 #include "all.h"
 
+#include <stdbool.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include <stdbool.h>
-#include <stdint.h>
 
 // Macros to make the YAJL API a bit easier to use.
 #define y(x, ...) (command_output.json_gen != NULL ? yajl_gen_##x(command_output.json_gen, ##__VA_ARGS__) : 0)
diff --git a/src/con.c b/src/con.c
index 08bb7e4ed..d9a792214 100644
--- a/src/con.c
+++ b/src/con.c
@@ -10,7 +10,6 @@
  *
  */
 #include "all.h"
-
 #include "yajl_utils.h"
 
 static void con_on_remove_child(Con *con);
diff --git a/src/config_parser.c b/src/config_parser.c
index f120cfa36..f78e75f83 100644
--- a/src/config_parser.c
+++ b/src/config_parser.c
@@ -25,16 +25,17 @@
  */
 #include "all.h"
 
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
-#include <stdbool.h>
-#include <stdint.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
-#include <sys/stat.h>
-#include <fcntl.h>
+#include <unistd.h>
+
 #include <xcb/xcb_xrm.h>
 
 // Macros to make the YAJL API a bit easier to use.
diff --git a/src/display_version.c b/src/display_version.c
index e44540e08..1fff8b8e4 100644
--- a/src/display_version.c
+++ b/src/display_version.c
@@ -10,12 +10,12 @@
  */
 #include "all.h"
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/wait.h>
+#include <fcntl.h>
 #include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 #include <sys/un.h>
-#include <fcntl.h>
+#include <sys/wait.h>
 #include <time.h>
 
 static bool human_readable_key, loaded_config_file_name_key;
diff --git a/src/handlers.c b/src/handlers.c
index d6d6e20bc..c49ebf77c 100644
--- a/src/handlers.c
+++ b/src/handlers.c
@@ -10,9 +10,10 @@
  */
 #include "all.h"
 
-#include <time.h>
 #include <float.h>
 #include <sys/time.h>
+#include <time.h>
+
 #include <xcb/randr.h>
 #define SN_API_NOT_YET_FROZEN 1
 #include <libsn/sn-monitor.h>
diff --git a/src/ipc.c b/src/ipc.c
index 75fa8ee74..7e62b1024 100644
--- a/src/ipc.c
+++ b/src/ipc.c
@@ -7,16 +7,17 @@
  * ipc.c: UNIX domain socket IPC (initialization, client handling, protocol).
  *
  */
-#include "all.h"
 
+#include "all.h"
 #include "yajl_utils.h"
 
+#include <ev.h>
+#include <fcntl.h>
+#include <libgen.h>
 #include <stdint.h>
 #include <sys/socket.h>
 #include <sys/un.h>
-#include <fcntl.h>
-#include <libgen.h>
-#include <ev.h>
+
 #include <yajl/yajl_gen.h>
 #include <yajl/yajl_parse.h>
 
diff --git a/src/log.c b/src/log.c
index 31db8b33c..73093da1f 100644
--- a/src/log.c
+++ b/src/log.c
@@ -9,27 +9,27 @@
  */
 #include <config.h>
 
+#include "i3.h"
+#include "libi3.h"
+#include "log.h"
+#include "shmlog.h"
+#include "util.h"
+
+#include <errno.h>
+#include <fcntl.h>
 #include <stdarg.h>
-#include <stdio.h>
-#include <string.h>
 #include <stdbool.h>
+#include <stdio.h>
 #include <stdlib.h>
-#include <sys/time.h>
-#include <unistd.h>
-#include <fcntl.h>
+#include <string.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
-#include <errno.h>
+#include <sys/time.h>
+#include <unistd.h>
 #if !defined(__OpenBSD__)
 #include <pthread.h>
 #endif
 
-#include "util.h"
-#include "log.h"
-#include "i3.h"
-#include "libi3.h"
-#include "shmlog.h"
-
 #if defined(__APPLE__)
 #include <sys/sysctl.h>
 #endif
diff --git a/src/main.c b/src/main.c
index 369f2f66d..c64bf43d7 100644
--- a/src/main.c
+++ b/src/main.c
@@ -8,18 +8,18 @@
  *
  */
 #include "all.h"
+#include "shmlog.h"
 
 #include <ev.h>
 #include <fcntl.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <sys/time.h>
-#include <sys/resource.h>
+#include <libgen.h>
 #include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
 #include <sys/stat.h>
-#include <libgen.h>
-#include "shmlog.h"
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/un.h>
 
 #ifdef I3_ASAN_ENABLED
 #include <sanitizer/lsan_interface.h>
diff --git a/src/manage.c b/src/manage.c
index eecba95c5..da5751dc6 100644
--- a/src/manage.c
+++ b/src/manage.c
@@ -8,7 +8,6 @@
  *
  */
 #include "all.h"
-
 #include "yajl_utils.h"
 
 #include <yajl/yajl_gen.h>
diff --git a/src/randr.c b/src/randr.c
index b163eca7d..56b0707fc 100644
--- a/src/randr.c
+++ b/src/randr.c
@@ -12,6 +12,7 @@
 #include "all.h"
 
 #include <time.h>
+
 #include <xcb/randr.h>
 
 /* Pointer to the result of the query for primary output */
diff --git a/src/sd-daemon.c b/src/sd-daemon.c
index 28a88bfd7..84761025b 100644
--- a/src/sd-daemon.c
+++ b/src/sd-daemon.c
@@ -28,21 +28,21 @@
 #define _GNU_SOURCE
 #endif
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <sys/fcntl.h>
-#include <netinet/in.h>
-#include <stdlib.h>
+#include "sd-daemon.h"
+
 #include <errno.h>
-#include <unistd.h>
-#include <string.h>
+#include <netinet/in.h>
 #include <stdarg.h>
-#include <stdio.h>
 #include <stddef.h>
-
-#include "sd-daemon.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
 
 int sd_listen_fds(int unset_environment) {
     int r, fd;
diff --git a/src/sighandler.c b/src/sighandler.c
index 86921b400..90e6c798d 100644
--- a/src/sighandler.c
+++ b/src/sighandler.c
@@ -12,9 +12,8 @@
 #include <signal.h>
 #include <sys/wait.h>
 
-#include <xcb/xcb_event.h>
-
 #include <X11/keysym.h>
+#include <xcb/xcb_event.h>
 
 typedef struct dialog_t {
     xcb_window_t id;
diff --git a/src/startup.c b/src/startup.c
index e994e0a8d..759b373c7 100644
--- a/src/startup.c
+++ b/src/startup.c
@@ -11,12 +11,11 @@
  *
  */
 #include "all.h"
-
 #include "sd-daemon.h"
 
+#include <paths.h>
 #include <sys/types.h>
 #include <sys/wait.h>
-#include <paths.h>
 
 #define SN_API_NOT_YET_FROZEN 1
 #include <libsn/sn-launcher.h>
diff --git a/src/util.c b/src/util.c
index 3544297c9..a21c7e5fb 100644
--- a/src/util.c
+++ b/src/util.c
@@ -10,16 +10,17 @@
  */
 #include "all.h"
 
-#include <sys/wait.h>
 #include <stdarg.h>
+#include <sys/wait.h>
 #if defined(__OpenBSD__)
 #include <sys/cdefs.h>
 #endif
+#include <ctype.h>
 #include <fcntl.h>
+#include <libgen.h>
 #include <pwd.h>
+
 #include <yajl/yajl_version.h>
-#include <libgen.h>
-#include <ctype.h>
 
 #define SN_API_NOT_YET_FROZEN 1
 #include <libsn/sn-launcher.h>
diff --git a/src/xcursor.c b/src/xcursor.c
index cffb094b1..9b4996ea8 100644
--- a/src/xcursor.c
+++ b/src/xcursor.c
@@ -9,13 +9,13 @@
  */
 #include <config.h>
 
+#include "i3.h"
+#include "xcb.h"
+
 #include <assert.h>
 #include <err.h>
-#include <xcb/xcb_cursor.h>
 
-#include "i3.h"
-#include "xcb.h"
-#include "xcursor.h"
+#include <xcb/xcb_cursor.h>
 
 static xcb_cursor_context_t *ctx;
 static xcb_cursor_t cursors[XCURSOR_CURSOR_MAX];
diff --git a/testcases/inject_randr1.5.c b/testcases/inject_randr1.5.c
index 819c029ba..0b7512280 100644
--- a/testcases/inject_randr1.5.c
+++ b/testcases/inject_randr1.5.c
@@ -16,15 +16,15 @@
 
 #include <ev.h>
 #include <fcntl.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <sys/time.h>
-#include <sys/resource.h>
+#include <libgen.h>
 #include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
 #include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/un.h>
 #include <sys/wait.h>
-#include <libgen.h>
 
 static void uds_connection_cb(EV_P_ ev_io *w, int revents);
 static void read_client_setup_request_cb(EV_P_ ev_io *w, int revents);