diff --git a/Makefile b/Makefile
index 1f891c5..592ddc1 100644
--- a/Makefile
+++ b/Makefile
@@ -3,9 +3,12 @@ LDLIBS += -lm
 
 all: img2cpi cpi2png wsvpn
 
-img2cpi: img2cpi.c cc-common.o
+img2cpi: img2cpi.c cc-common.o dependencies/stb/stb_image.o dependencies/stb/stb_image_resize2.o
 	$(CC) $(LDFLAGS) $^ $(LDLIBS) -o "$@"
 
+dependencies/stb/%.o: dependencies/stb/%.h
+	$(CC) -DSTB_IMAGE_IMPLEMENTATION -DSTB_IMAGE_RESIZE_IMPLEMENTATION -DSTB_IMAGE_WRITE_IMPLEMENTATION -x c $^ -c -o "$@"
+
 wsvpn: wsvpn.o dependencies/mongoose/mongoose.o
 	$(CC) $(LDFLAGS) $^ $(LOADLIBES) $(LDLIBS) -o "$@"
 
diff --git a/img2cpi.c b/img2cpi.c
index cfe1d7c..743bc0a 100644
--- a/img2cpi.c
+++ b/img2cpi.c
@@ -1,8 +1,8 @@
 // x-run: make img2cpi CC=clang
 // x-run: ~/scripts/runc.sh % -Wall -Wextra -lm --- ~/images/boykisser.png cpi-images/boykisser.cpi
-#define STB_IMAGE_IMPLEMENTATION
+#include <math.h>
+#include <assert.h>
 #include <stb/stb_image.h>
-#define STB_IMAGE_RESIZE_IMPLEMENTATION
 #include <stb/stb_image_resize2.h>
 #include <argp.h>
 #include <stdio.h>