diff --git a/Makefile b/Makefile
index b38ab8f..f05bc3c 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 prefix = /usr/bin
 
-YAIT_SRCS := $(wildcard yait/*.c)
+YAIT_SRCS := $(wildcard yait/*.c) $(wildcard lib/*.c)
 
 YAIT_OBJS := $(patsubst yait/%.c,obj/yait/%.o,$(YAIT_SRCS))
 
diff --git a/bin/yait b/bin/yait
new file mode 100755
index 0000000..7ac3f47
Binary files /dev/null and b/bin/yait differ
diff --git a/config.mak b/config.mak
new file mode 100644
index 0000000..d6ba4f4
--- /dev/null
+++ b/config.mak
@@ -0,0 +1,4 @@
+PREFIX=/usr/bin/
+CFLAGS=-Wall -Wextra -O2
+LDFLAGS=
+CC=gcc
diff --git a/lib/print.c b/lib/print.c
index 59178ff..6b6f694 100644
--- a/lib/print.c
+++ b/lib/print.c
@@ -6,7 +6,7 @@ int printfn(char *format, ...) {
   int len;
   va_list args;
   va_start(args, format);
-  printf("yait: ");
+  fprintf(stderr, "yait: ");
   len = vfprintf(stderr, format, args);
   putchar('\n');
   va_end(args);
diff --git a/obj/yait/main.o b/obj/yait/main.o
new file mode 100644
index 0000000..bcb307d
Binary files /dev/null and b/obj/yait/main.o differ
diff --git a/yait/main.c b/yait/main.c
index 84528da..58db290 100644
--- a/yait/main.c
+++ b/yait/main.c
@@ -1,6 +1,6 @@
-#include <stdio.h>
+#include "../lib/print.h"
 
 int main(void) {
-  printf("Hello, Yait!\n");
+  printfn("error: incomplete binary.");
   return 0;
 }