diff --git a/extra/classes/c-types/c-types-docs.factor b/extra/classes/c-types/c-types-docs.factor
index f3d1258583..58ebf7a063 100644
--- a/extra/classes/c-types/c-types-docs.factor
+++ b/extra/classes/c-types/c-types-docs.factor
@@ -1,5 +1,6 @@
 ! (c)Joe Groff bsd license
-USING: alien arrays classes help.markup help.syntax kernel math ;
+USING: alien arrays classes help.markup help.syntax kernel math
+specialized-arrays.direct ;
 IN: classes.c-types
 
 HELP: c-type-class