diff --git a/core.rkt b/core.rkt
index 6bb4b40..ac53848 100644
--- a/core.rkt
+++ b/core.rkt
@@ -1,6 +1,6 @@
 #lang racket/base
 (require racket/string racket/list)
-(require sugar/string sugar/coerce)
+(require sugar/unstable/string sugar/coerce)
 
 (provide (all-defined-out))