diff --git a/sources/c.h b/sources/c.h
index 02e2738a..7a3ee854 100644
--- a/sources/c.h
+++ b/sources/c.h
@@ -11,9 +11,16 @@
 #include <stdarg.h>
 #include <stdint.h>
 #include <stdio.h>
+
 #include <string.h>
 #include <ctype.h>
 #include <inttypes.h>
 #include <assert.h>
 
+#include <signal.h>
+#include <errno.h>
+
+#include <sys/time.h>
+#include <sys/resource.h>
+
 #endif // ODYSSEY_C_H
diff --git a/sources/counter.h b/sources/counter.h
index 36a39234..ee184a02 100644
--- a/sources/counter.h
+++ b/sources/counter.h
@@ -1,4 +1,3 @@
-
 #ifndef ODYSSEY_COUNTER_H
 #define ODYSSEY_COUNTER_H
 
diff --git a/sources/cron.c b/sources/cron.c
index 3e91de60..ea909c06 100644
--- a/sources/cron.c
+++ b/sources/cron.c
@@ -5,18 +5,7 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
-#include <machinarium.h>
-#include <kiwi.h>
-#include <odyssey.h>
+#include "cron.h"
 
 static int
 od_cron_stat_cb(od_route_t *route,
diff --git a/sources/cron.h b/sources/cron.h
index 14b319e8..85f78934 100644
--- a/sources/cron.h
+++ b/sources/cron.h
@@ -9,6 +9,11 @@
 
 typedef struct od_cron od_cron_t;
 
+#include "c.h"
+
+#include <machinarium.h>
+#include <odyssey.h>
+
 struct od_cron
 {
 	uint64_t stat_time_us;
diff --git a/sources/daemon.c b/sources/daemon.c
index 18feacf8..3d7681f4 100644
--- a/sources/daemon.c
+++ b/sources/daemon.c
@@ -5,23 +5,7 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-
-#include <machinarium.h>
-#include <kiwi.h>
-#include <odyssey.h>
+#include "daemon.h"
 
 int
 od_daemonize(void)
diff --git a/sources/daemon.h b/sources/daemon.h
index 99fd659d..b40dc216 100644
--- a/sources/daemon.h
+++ b/sources/daemon.h
@@ -7,6 +7,10 @@
  * Scalable PostgreSQL connection pooler.
  */
 
+#include <unistd.h>
+#include <fcntl.h>
+#include <odyssey.h>
+
 int
 od_daemonize(void);
 
diff --git a/sources/deploy.c b/sources/deploy.c
index a17d28de..eafc97cf 100644
--- a/sources/deploy.c
+++ b/sources/deploy.c
@@ -5,15 +5,6 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <machinarium.h>
 #include <kiwi.h>
 #include <odyssey.h>
diff --git a/sources/dns.c b/sources/dns.c
index 5a70c075..849e44b7 100644
--- a/sources/dns.c
+++ b/sources/dns.c
@@ -5,20 +5,10 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
 #include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 
 static int
diff --git a/sources/frontend.c b/sources/frontend.c
index e136bfd0..84ba176e 100644
--- a/sources/frontend.c
+++ b/sources/frontend.c
@@ -5,12 +5,7 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <string.h>
-#include <inttypes.h>
-#include <assert.h>
+#include "c.h"
 
 #include <machinarium.h>
 #include <kiwi.h>
diff --git a/sources/grac_shutdown_worker.c b/sources/grac_shutdown_worker.c
index 888b54ea..ecad051d 100644
--- a/sources/grac_shutdown_worker.c
+++ b/sources/grac_shutdown_worker.c
@@ -1,21 +1,5 @@
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
 
-#include <unistd.h>
-#include <signal.h>
-#include <sys/stat.h>
-#include <errno.h>
-
-#include <machinarium.h>
-#include <kiwi.h>
-#include <odyssey.h>
-#include <sys/prctl.h>
+#include "grac_shutdown_worker.h"
 
 static inline int
 od_system_server_complete_stop(od_system_server_t *server)
diff --git a/sources/grac_shutdown_worker.h b/sources/grac_shutdown_worker.h
index 9145527e..3a5d37fd 100644
--- a/sources/grac_shutdown_worker.h
+++ b/sources/grac_shutdown_worker.h
@@ -7,6 +7,13 @@
  * Scalable PostgreSQL connection pooler.
  */
 
+#include <string.h>
+#include <signal.h>
+
+#include <machinarium.h>
+#include <kiwi.h>
+#include <odyssey.h>
+
 void
 od_grac_shutdown_worker(void *arg);
 
diff --git a/sources/instance.c b/sources/instance.c
index 10af00dc..f5841620 100644
--- a/sources/instance.c
+++ b/sources/instance.c
@@ -5,22 +5,9 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
-#include <signal.h>
-#include <errno.h>
-#include <sys/time.h>
-#include <sys/resource.h>
+#include "c.h"
 
 #include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 #include "module.h"
 
diff --git a/sources/logger.c b/sources/logger.c
index 6d6fcf85..77ffa786 100644
--- a/sources/logger.c
+++ b/sources/logger.c
@@ -5,25 +5,14 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <unistd.h>
 #include <fcntl.h>
-#include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <time.h>
 #include <syslog.h>
 
 #include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 
 typedef struct
diff --git a/sources/main.c b/sources/main.c
index c5e6047c..ef359a6e 100644
--- a/sources/main.c
+++ b/sources/main.c
@@ -6,16 +6,6 @@
  */
 
 #include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
-#include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 
 int
diff --git a/sources/pid.c b/sources/pid.c
index 79b409ae..39a0f113 100644
--- a/sources/pid.c
+++ b/sources/pid.c
@@ -5,23 +5,8 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <unistd.h>
 #include <fcntl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/time.h>
-
-#include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 
 void
diff --git a/sources/reset.c b/sources/reset.c
index bd1b235e..3d880402 100644
--- a/sources/reset.c
+++ b/sources/reset.c
@@ -5,17 +5,9 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
 #include <assert.h>
 
 #include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 
 int
diff --git a/sources/router.c b/sources/router.c
index a3060ac1..679375ae 100644
--- a/sources/router.c
+++ b/sources/router.c
@@ -5,13 +5,6 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
 #include <assert.h>
 
 #include <machinarium.h>
diff --git a/sources/rules.c b/sources/rules.c
index 4f3da1e8..241999f1 100644
--- a/sources/rules.c
+++ b/sources/rules.c
@@ -5,15 +5,6 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <machinarium.h>
 #include <kiwi.h>
 #include <odyssey.h>
diff --git a/sources/system.c b/sources/system.c
index 914cb4a1..3db94f9a 100644
--- a/sources/system.c
+++ b/sources/system.c
@@ -5,14 +5,6 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdint.h>
-#include <string.h>
-
-#include <unistd.h>
-#include <sys/stat.h>
-#include <errno.h>
-
 #include <machinarium.h>
 #include <kiwi.h>
 #include <odyssey.h>
diff --git a/sources/tls.c b/sources/tls.c
index 4284850f..bbf056a3 100644
--- a/sources/tls.c
+++ b/sources/tls.c
@@ -5,15 +5,6 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <machinarium.h>
 #include <kiwi.h>
 #include <odyssey.h>
diff --git a/sources/worker.c b/sources/worker.c
index 445b06b7..02554c12 100644
--- a/sources/worker.c
+++ b/sources/worker.c
@@ -5,17 +5,7 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <inttypes.h>
-#include <assert.h>
-
 #include <machinarium.h>
-#include <kiwi.h>
 #include <odyssey.h>
 
 static inline void