diff --git a/Makefile b/Makefile
index 3902c62..01c0662 100644
--- a/Makefile
+++ b/Makefile
@@ -6,8 +6,8 @@ include config.mk
 CFLAGS += -I.
 LDFLAGS += -L.
 
-SRC = $(shell ls src/*.c)
-OBJ = ${SRC:.c=.o}
+SRC := $(shell find src/ -name '*.c')
+OBJ := ${SRC:.c=.o}
 
 all: doc dunst service
 
@@ -76,8 +76,8 @@ uninstall:
 test: test/test
 	cd test && ./test
 
-TEST_SRC = $(shell ls test/*.c)
-TEST_OBJ = $(TEST_SRC:.c=.o)
+TEST_SRC := $(shell find test/ -name '*.c')
+TEST_OBJ := $(TEST_SRC:.c=.o)
 
 test/test: ${OBJ} ${TEST_OBJ}
 	${CC} ${CFLAGS} -o $@ ${TEST_OBJ} ${OBJ} ${LDFLAGS}
diff --git a/src/dunst.c b/src/dunst.c
index 3a6008c..9f2c0b9 100644
--- a/src/dunst.c
+++ b/src/dunst.c
@@ -19,7 +19,7 @@
 #include "notification.h"
 #include "option_parser.h"
 #include "settings.h"
-#include "x.h"
+#include "x11/x.h"
 
 #define LENGTH(X)               (sizeof X / sizeof X[0])
 
diff --git a/src/notification.c b/src/notification.c
index 930a0f8..1ccb7c1 100644
--- a/src/notification.c
+++ b/src/notification.c
@@ -21,7 +21,7 @@
 #include "rules.h"
 #include "settings.h"
 #include "utils.h"
-#include "x.h"
+#include "x11/x.h"
 
 int next_notification_id = 1;
 
diff --git a/src/settings.h b/src/settings.h
index 160da14..a5097f6 100644
--- a/src/settings.h
+++ b/src/settings.h
@@ -4,7 +4,7 @@
 
 #include <stdbool.h>
 
-#include "x.h"
+#include "x11/x.h"
 
 enum alignment { left, center, right };
 enum icon_position_t { icons_left, icons_right, icons_off };
diff --git a/src/x.c b/src/x11/x.c
similarity index 99%
rename from src/x.c
rename to src/x11/x.c
index b8745d0..9a2a5c8 100644
--- a/src/x.c
+++ b/src/x11/x.c
@@ -25,11 +25,11 @@
 #include <string.h>
 #include <unistd.h>
 
-#include "dunst.h"
-#include "markup.h"
-#include "notification.h"
-#include "settings.h"
-#include "utils.h"
+#include "src/dunst.h"
+#include "src/markup.h"
+#include "src/notification.h"
+#include "src/settings.h"
+#include "src/utils.h"
 
 #define WIDTH 400
 #define HEIGHT 400
diff --git a/src/x.h b/src/x11/x.h
similarity index 100%
rename from src/x.h
rename to src/x11/x.h