diff --git a/retropikzel/r7rs-pffi/version/guile.scm b/retropikzel/r7rs-pffi/version/guile.scm
index 04053f4..9cdb1a4 100644
--- a/retropikzel/r7rs-pffi/version/guile.scm
+++ b/retropikzel/r7rs-pffi/version/guile.scm
@@ -33,8 +33,8 @@
               ((equal? type 'uint32) uint32)
               ((equal? type 'int64) int64)
               ((equal? type 'uint64) uint64)
-              ((equal? type 'char) int)
-              ((equal? type 'unsigned-char) int)
+              ((equal? type 'char) int8)
+              ((equal? type 'unsigned-char) int8)
               ((equal? type 'short) short)
               ((equal? type 'unsigned-short) unsigned-short)
               ((equal? type 'int) int)