diff --git a/utils.rkt b/utils.rkt
index 73ba3ce..d2ce7f7 100644
--- a/utils.rkt
+++ b/utils.rkt
@@ -1,6 +1,6 @@
 #lang typed/racket
 
-(require typed/graph typed/rackunit typed-compose typed/racket/stream
+(require typed/graph typed-compose typed/racket/stream
          (for-syntax syntax/parse racket/list))
 
 (provide
@@ -19,6 +19,9 @@
 
  variable-mapping?)
 
+(module+ test
+  (require typed/rackunit))
+
 (define-type Variable Symbol)
 (define-type (VariableMapping A) (Immutable-HashTable Variable A))