diff --git a/.clang-format b/.clang-format
index 6e68f2a..f317044 100644
--- a/.clang-format
+++ b/.clang-format
@@ -28,5 +28,14 @@ SpacesInParentheses: 'false'
 Standard: Cpp11
 TabWidth: '2'
 UseTab: ForIndentation
+IncludeCategories:
+  - Regex:           '^"(llvm-c|clang-c)/'
+    Priority:        2
+  - Regex:           '^"(llvm|clang)/'
+    Priority:        3
+  - Regex:           '^(<|"(gtest|isl|json)/)'
+    Priority:        4
+  - Regex:           '.*'
+    Priority:        1
 
 ...
diff --git a/include/genimg/common.hh b/include/genimg/common.hh
index 7da98ee..cfb9b69 100644
--- a/include/genimg/common.hh
+++ b/include/genimg/common.hh
@@ -1,9 +1,9 @@
 #ifndef GENETIC_IMAGE_INCLUDE_GENIMG_COMMON_HH_
 #define GENETIC_IMAGE_INCLUDE_GENIMG_COMMON_HH_
 
-#include <spdlog/spdlog.h>
 #include <opencv2/core/core.hpp>
 #include <opencv2/highgui/highgui.hpp>
+#include <spdlog/spdlog.h>
 #include <string>
 #include <utility>
 
diff --git a/include/genimg/methods.hh b/include/genimg/methods.hh
index 392ac36..f727876 100644
--- a/include/genimg/methods.hh
+++ b/include/genimg/methods.hh
@@ -1,9 +1,9 @@
 #ifndef GENETIC_IMAGE_INCLUDE_GENIMG_METHODS_HH_
 #define GENETIC_IMAGE_INCLUDE_GENIMG_METHODS_HH_
 
-#include <spdlog/spdlog.h>
 #include <opencv2/core/core.hpp>
 #include <opencv2/highgui/highgui.hpp>
+#include <spdlog/spdlog.h>
 
 void method1(cv::Mat const&, cv::Mat&, int);
 
diff --git a/src/drawing.cc b/src/drawing.cc
index f9ca480..e80c316 100644
--- a/src/drawing.cc
+++ b/src/drawing.cc
@@ -1,8 +1,8 @@
 #include "drawing.hh"
-#include <spdlog/spdlog.h>
 #include <cstdlib>
 #include <memory>
 #include <opencv2/imgproc.hpp>
+#include <spdlog/spdlog.h>
 
 void drawSquare(cv::Mat& t_img,
                 cv::Point const& t_top_left,
diff --git a/src/main.cc b/src/main.cc
index 81e45a5..838b0b0 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -1,9 +1,9 @@
-#include <cstdlib>
-#include <ctime>
-#include <iostream>
 #include "common.hh"
 #include "methods.hh"
 #include "parseargs.hh"
+#include <cstdlib>
+#include <ctime>
+#include <iostream>
 
 int main(int ac, char** av)
 {
diff --git a/src/methods.cc b/src/methods.cc
index 727dd7c..882cc88 100644
--- a/src/methods.cc
+++ b/src/methods.cc
@@ -1,11 +1,11 @@
 #include "methods.hh"
+#include "common.hh"
+#include "drawing.hh"
 #include <algorithm>
 #include <array>
 #include <cstdlib>
 #include <thread>
 #include <vector>
-#include "common.hh"
-#include "drawing.hh"
 
 auto const thread_nbr = std::thread::hardware_concurrency();
 std::mutex numbers_mutex;