diff --git a/core/bootstrap/syntax.factor b/core/bootstrap/syntax.factor
index e7e90d8dd0..e5a439c32b 100755
--- a/core/bootstrap/syntax.factor
+++ b/core/bootstrap/syntax.factor
@@ -43,6 +43,7 @@ IN: bootstrap.syntax
     "PRIMITIVE:"
     "PRIVATE>"
     "SBUF\""
+    "SINLETON:"
     "SYMBOL:"
     "TUPLE:"
     "T{"
diff --git a/extra/classes/singleton/authors.txt b/core/classes/singleton/authors.txt
similarity index 100%
rename from extra/classes/singleton/authors.txt
rename to core/classes/singleton/authors.txt
diff --git a/extra/classes/singleton/singleton-docs.factor b/core/classes/singleton/singleton-docs.factor
similarity index 100%
rename from extra/classes/singleton/singleton-docs.factor
rename to core/classes/singleton/singleton-docs.factor
diff --git a/extra/classes/singleton/singleton-tests.factor b/core/classes/singleton/singleton-tests.factor
similarity index 75%
rename from extra/classes/singleton/singleton-tests.factor
rename to core/classes/singleton/singleton-tests.factor
index 586724ee3b..11a2a2d166 100644
--- a/extra/classes/singleton/singleton-tests.factor
+++ b/core/classes/singleton/singleton-tests.factor
@@ -9,4 +9,4 @@ GENERIC: zammo ( obj -- )
 [ "yes!" ] [ bzzt zammo ] unit-test
 [ ] [ SINGLETON: omg ] unit-test
 [ t ] [ omg singleton? ] unit-test
-[ "USING: classes.singleton ;\nIN: classes.singleton.tests\nSINGLETON: omg\n" ] [ [ omg see ] with-string-writer ] unit-test
+[ "IN: classes.singleton.tests\nSINGLETON: omg\n" ] [ [ omg see ] with-string-writer ] unit-test
diff --git a/extra/classes/singleton/singleton.factor b/core/classes/singleton/singleton.factor
similarity index 92%
rename from extra/classes/singleton/singleton.factor
rename to core/classes/singleton/singleton.factor
index 61a519679c..13fd242dad 100755
--- a/extra/classes/singleton/singleton.factor
+++ b/core/classes/singleton/singleton.factor
@@ -15,8 +15,5 @@ PREDICATE: singleton < predicate-class
     \ singleton
     over [ eq? ] curry define-predicate-class ;
 
-: SINGLETON:
-    scan define-singleton ; parsing
-
 M: singleton see-class* ( class -- )
     <colon \ SINGLETON: pprint-word pprint-word ;
diff --git a/core/syntax/syntax.factor b/core/syntax/syntax.factor
index 19fdf0e45f..1191752ed7 100755
--- a/core/syntax/syntax.factor
+++ b/core/syntax/syntax.factor
@@ -6,7 +6,7 @@ namespaces parser sequences strings sbufs vectors words
 quotations io assocs splitting classes.tuple generic.standard
 generic.math classes io.files vocabs float-arrays float-vectors
 classes.union classes.mixin classes.predicate compiler.units
-combinators debugger ;
+combinators debugger classes.singleton ;
 IN: bootstrap.syntax
 
 ! These words are defined as a top-level form, instead of with
@@ -154,6 +154,10 @@ IN: bootstrap.syntax
         parse-definition define-predicate-class
     ] define-syntax
 
+    "SINGLETON:" [
+        scan define-singleton
+    ] define-syntax
+
     "TUPLE:" [
         parse-tuple-definition define-tuple-class
     ] define-syntax