diff --git a/.clang-format b/.clang-format
index 56335676..73bb0409 100644
--- a/.clang-format
+++ b/.clang-format
@@ -7,3 +7,23 @@ AllowShortFunctionsOnASingleLine: false
 AlignConsecutiveMacros: true
 IndentCaseLabels: true
 ColumnLimit: 100
+IncludeBlocks: Regroup
+
+# Include block order goes like this
+# - config.h style files, including ../config.h
+# - system headers (<>)
+# - All m1n1 headers, starting with the "this file" header, rest sorted
+# - 3rd party code headers
+# - build artifact headers (stuff outside of src/)
+IncludeCategories:
+  - Regex:           '^"(\.\./)*config\.h"$'
+    Priority:        -2
+  - Regex:           '^<'
+    Priority:        -1
+  - Regex:           '^"\.\./'
+    Priority:        3
+  - Regex:           '/'
+    Priority:        2
+  - Regex:           '.*'
+    Priority:        0
+    SortPriority:    1
diff --git a/src/adt.h b/src/adt.h
index 6497a2f0..78934e1e 100644
--- a/src/adt.h
+++ b/src/adt.h
@@ -3,10 +3,11 @@
 #ifndef XDT_H
 #define XDT_H
 
-#include "types.h"
 #include <stddef.h>
 #include <stdint.h>
 
+#include "types.h"
+
 #define ADT_ERR_NOTFOUND  1
 #define ADT_ERR_BADOFFSET 4
 #define ADT_ERR_BADPATH   5
diff --git a/src/kboot.c b/src/kboot.c
index 030ba7f4..ff381eb0 100644
--- a/src/kboot.c
+++ b/src/kboot.c
@@ -5,7 +5,6 @@
 #include "adt.h"
 #include "exception.h"
 #include "kboot.h"
-#include "libfdt/libfdt.h"
 #include "malloc.h"
 #include "memory.h"
 #include "smp.h"
@@ -13,6 +12,8 @@
 #include "utils.h"
 #include "xnuboot.h"
 
+#include "libfdt/libfdt.h"
+
 static void *dt = NULL;
 static int dt_bufsize = 0;
 static char *bootargs = NULL;
diff --git a/src/proxy.c b/src/proxy.c
index 7cb699a7..c2bc7dca 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -4,14 +4,15 @@
 #include "kboot.h"
 #include "malloc.h"
 #include "memory.h"
-#include "minilzlib/minlzma.h"
 #include "smp.h"
-#include "tinf/tinf.h"
 #include "types.h"
 #include "uart.h"
 #include "utils.h"
 #include "xnuboot.h"
 
+#include "minilzlib/minlzma.h"
+#include "tinf/tinf.h"
+
 int proxy_process(ProxyRequest *request, ProxyReply *reply)
 {
     enum exc_guard_t guard_save = exc_guard;
diff --git a/src/utils.c b/src/utils.c
index 5cf85179..00270d77 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -1,12 +1,12 @@
 /* SPDX-License-Identifier: MIT */
 
+#include <stdarg.h>
+
 #include "utils.h"
 #include "types.h"
 #include "uart.h"
 #include "vsprintf.h"
 
-#include <stdarg.h>
-
 static char ascii(char s)
 {
     if (s < 0x20)
diff --git a/src/vsprintf.c b/src/vsprintf.c
index 47c36ea1..1f2b1827 100644
--- a/src/vsprintf.c
+++ b/src/vsprintf.c
@@ -93,9 +93,10 @@
  * 	2.5 printf(3S) man page.
  */
 
-#include "types.h"
 #include <stdarg.h>
 
+#include "types.h"
+
 #define VA_START(ap, last)        va_start(ap, last)
 #define VA_SHIFT(ap, value, type) /* No-op for ANSI C. */