diff --git a/extra/singleton/authors.txt b/extra/classes/singleton/authors.txt
similarity index 100%
rename from extra/singleton/authors.txt
rename to extra/classes/singleton/authors.txt
diff --git a/extra/singleton/singleton-docs.factor b/extra/classes/singleton/singleton-docs.factor
similarity index 96%
rename from extra/singleton/singleton-docs.factor
rename to extra/classes/singleton/singleton-docs.factor
index 7acf97a436..95b5b6af18 100644
--- a/extra/singleton/singleton-docs.factor
+++ b/extra/classes/singleton/singleton-docs.factor
@@ -1,5 +1,5 @@
 USING: help.markup help.syntax kernel words ;
-IN: singleton
+IN: classes.singleton
 
 HELP: SINGLETON:
 { $syntax "SINGLETON: class"
diff --git a/extra/singleton/singleton-tests.factor b/extra/classes/singleton/singleton-tests.factor
similarity index 70%
rename from extra/singleton/singleton-tests.factor
rename to extra/classes/singleton/singleton-tests.factor
index da2a74f8d1..453a2a0ea5 100644
--- a/extra/singleton/singleton-tests.factor
+++ b/extra/classes/singleton/singleton-tests.factor
@@ -1,5 +1,5 @@
 USING: kernel singleton tools.test prettyprint io.streams.string ;
-IN: singleton.tests
+IN: classes.singleton.tests
 
 [ ] [ SINGLETON: bzzt ] unit-test
 [ t ] [ bzzt bzzt? ] unit-test
@@ -9,4 +9,4 @@ GENERIC: zammo ( obj -- )
 [ "yes!" ] [ bzzt zammo ] unit-test
 [ ] [ SINGLETON: omg ] unit-test
 [ t ] [ omg singleton? ] unit-test
-[ "USING: singleton ;\nIN: singleton.tests\nSINGLETON: omg\n" ] [ [ omg see ] with-string-writer ] unit-test
+[ "USING: singleton ;\nIN: classes.singleton.tests\nSINGLETON: omg\n" ] [ [ omg see ] with-string-writer ] unit-test
diff --git a/extra/singleton/singleton.factor b/extra/classes/singleton/singleton.factor
similarity index 95%
rename from extra/singleton/singleton.factor
rename to extra/classes/singleton/singleton.factor
index 99319fdfdb..61a519679c 100755
--- a/extra/singleton/singleton.factor
+++ b/extra/classes/singleton/singleton.factor
@@ -3,8 +3,7 @@
 USING: classes.predicate kernel namespaces parser quotations
 sequences words prettyprint prettyprint.backend prettyprint.sections
 compiler.units classes ;
-USE: tools.walker
-IN: singleton
+IN: classes.singleton
 
 PREDICATE: singleton < predicate-class
     [ "predicate-definition" word-prop ]