diff --git a/basis/bootstrap/tools/tools.factor b/basis/bootstrap/tools/tools.factor
index 51f44025c9..c76d4f7898 100644
--- a/basis/bootstrap/tools/tools.factor
+++ b/basis/bootstrap/tools/tools.factor
@@ -1,4 +1,4 @@
-USING: vocabs.loader sequences ;
+USING: vocabs.loader sequences system combinators ;
 IN: bootstrap.tools
 
 {
@@ -23,3 +23,8 @@ IN: bootstrap.tools
     "vocabs.refresh"
     "vocabs.refresh.monitor"
 } [ require ] each
+
+{
+    { [ os windows? ] [ "debugger.windows" require ] }
+    { [ os unix? ] [ "debugger.unix" require ] }
+} cond
diff --git a/basis/debugger/debugger.factor b/basis/debugger/debugger.factor
index 8856871f11..eca34c2526 100644
--- a/basis/debugger/debugger.factor
+++ b/basis/debugger/debugger.factor
@@ -355,8 +355,3 @@ M: not-found-in-roots summary drop "Cannot resolve vocab: path" ;
 M: wrong-values summary drop "Quotation's stack effect does not match call site" ;
 
 M: stack-effect-omits-dashes summary drop "Stack effect must contain “--”" ;
-
-{
-    { [ os windows? ] [ "debugger.windows" require ] }
-    { [ os unix? ] [ "debugger.unix" require ] }
-} cond