diff --git a/Source/system/_sbrk.c b/Source/system/_sbrk.c
new file mode 100644
--- /dev/null
+++ b/Source/system/_sbrk.c
@@ -0,0 +1,22 @@
+//
+// sbrk: basic implementation of _sbrk for sprintf and other stdlib functions
+//
+
+#include <sys/stat.h>
+
+caddr_t _sbrk(int incr)
+{
+extern char end asm("end");
+static char *heap_end;
+char *prev_heap_end;
+
+if (heap_end == 0) {
+heap_end = &end;
+}
+
+prev_heap_end = heap_end;
+
+heap_end += incr;
+
+return (caddr_t)prev_heap_end;
+}