diff --git a/lib/scheme/base.sld b/lib/scheme/base.sld
index 66ba42d0..60fec9ea 100644
--- a/lib/scheme/base.sld
+++ b/lib/scheme/base.sld
@@ -40,7 +40,8 @@
    read-bytevector!  read-char read-error? read-line read-u8 real?  remainder
    reverse round set!  set-car!  set-cdr!  square string string->list
    string->number string->symbol string->utf8 string->vector string-append
-   string-copy string-fill!  string-for-each string-length string-map
+   string-copy string-copy! string-fill!  string-for-each string-length
+   string-map
    string-ref string-set!  string<=?  string<?  string=?  string>=?
    string>?  string?  substring symbol->string symbol?  symbol=?  syntax-error
    syntax-rules textual-port?  truncate u8-ready?  unless unquote