diff --git a/libs/util.sld b/libs/util.sld
index a4040f1..252663e 100644
--- a/libs/util.sld
+++ b/libs/util.sld
@@ -50,7 +50,7 @@
 
         (define-c-procedure c-system c-stdlib 'system 'int '(pointer))
         (define (system cmd)
-          (c-system (string->c-utf8 cmd)))))
+          (c-system (string->c-bytevector cmd)))))
     (define r6rs-schemes '(capyscheme
                             chezscheme
                             guile