diff --git a/extra/semantic-db/context/context.factor b/extra/semantic-db/context/context.factor
index 83da36712e..e103fbc92e 100644
--- a/extra/semantic-db/context/context.factor
+++ b/extra/semantic-db/context/context.factor
@@ -1,14 +1,14 @@
 ! Copyright (C) 2008 Alex Chapman
 ! See http://factorcode.org/license.txt for BSD license.
-USING: semantic-db ;
+USING: kernel semantic-db semantic-db.type ;
 IN: semantic-db.context
 
-: all-contexts ( -- contexts )
-    has-type-relation context-type relation-object-subjects ;
+! : all-contexts ( -- contexts )
+!     has-type-relation context-type relation-object-subjects ;
+! 
+! : context-relations ( context -- relations )
+!     has-context-relation swap relation-object-subjects ;
 
-: context-relations ( context -- relations )
-    has-context-relation swap relation-object-subjects ;
-    
-: get-context ( name -- context )
+: ensure-context ( name -- context-id )
     context-type swap ensure-node-of-type ;
 
diff --git a/extra/semantic-db/hierarchy/hierarchy.factor b/extra/semantic-db/hierarchy/hierarchy.factor
index fd4f74e33c..4feb3d8d6d 100644
--- a/extra/semantic-db/hierarchy/hierarchy.factor
+++ b/extra/semantic-db/hierarchy/hierarchy.factor
@@ -1,6 +1,27 @@
 ! Copyright (C) 2008 Alex Chapman
 ! See http://factorcode.org/license.txt for BSD license.
-USING: kernel semantic-db ;
+USING: accessors kernel new-slots semantic-db semantic-db.context sequences ;
 IN: semantic-db.hierarchy
 
+TUPLE: tree id children ;
+C: <tree> tree
 
+: hierarchy-context ( -- context-id )
+    "hierarchy" ensure-context ;
+
+: has-parent-relation ( -- relation-id )
+    ! find an arc with:
+    !   type = relation (in semantic-db context)
+    !   context = hierarchy
+    !   name = "has parent"
+    ;
+
+: find-children ( node-id -- children )
+    ! find arcs with:
+    !   relation = has-parent-relation
+    !   object = node-id
+    ! then load the subjects either as nodes or subtrees
+    ;
+
+: get-node-hierarchy ( node-id -- tree )
+    dup find-children <tree> ;
diff --git a/extra/semantic-db/semantic-db-tests.factor b/extra/semantic-db/semantic-db-tests.factor
index 440335b2c3..0096b89d34 100644
--- a/extra/semantic-db/semantic-db-tests.factor
+++ b/extra/semantic-db/semantic-db-tests.factor
@@ -3,9 +3,9 @@ IN: temporary
 
 [
     create-node-table create-arc-table
-    [ 1 ] [ "first node" create-node* ] unit-test
-    [ 2 ] [ "second node" create-node* ] unit-test
-    [ 3 ] [ "third node" create-node* ] unit-test
-    [ 4 ] [ f create-node* ] unit-test
-    [ 5 ] [ 1 2 3 create-arc* ] unit-test
+    [ 1 ] [ "first node" create-node ] unit-test
+    [ 2 ] [ "second node" create-node ] unit-test
+    [ 3 ] [ "third node" create-node ] unit-test
+    [ 4 ] [ f create-node ] unit-test
+    [ 5 ] [ 1 2 3 create-arc ] unit-test
 ] with-tmp-sqlite
diff --git a/extra/semantic-db/semantic-db.factor b/extra/semantic-db/semantic-db.factor
index 1205648b03..bd29dba5f8 100644
--- a/extra/semantic-db/semantic-db.factor
+++ b/extra/semantic-db/semantic-db.factor
@@ -18,12 +18,9 @@ node "node"
 : create-node-table ( -- )
     node create-table ;
 
-: create-node* ( content -- id )
+: create-node ( content -- id )
     <node> dup persist id>> ;
 
-: create-node ( content -- )
-    create-node* drop ;
-
 TUPLE: arc relation subject object ;
 
 : <arc> ( relation subject object -- arc )
@@ -41,7 +38,6 @@ arc "arc"
 
 : create-arc-table ( -- )
     arc create-table ;
-    ! arc db-columns maybe-remove-id arc db-table create-sql sql-command ;
 
 : insert-arc ( arc -- )
     dup delegate insert-tuple
@@ -53,15 +49,12 @@ arc "arc"
 : delete-arc ( arc -- )
     dup delete-tuple delegate delete-tuple ;
 
-: create-arc* ( relation subject object -- id )
+: create-arc ( relation subject object -- id )
     <arc> dup persist-arc id>> ;
 
-: create-arc ( relation subject object -- )
-    create-arc* drop ;
-
 : create-bootstrap-nodes ( -- )
     { "context" "relation" "is of type" "semantic-db" "is in context" }
-    [ create-node ] each ;
+    [ create-node drop ] each ;
 
 : context-type 1 ; inline
 : relation-type 2 ; inline
@@ -70,11 +63,11 @@ arc "arc"
 : has-context-relation 5 ; inline
 
 : create-bootstrap-arcs ( -- )
-    has-type-relation has-type-relation relation-type create-arc
-    has-type-relation semantic-db-context context-type create-arc
-    has-context-relation has-type-relation semantic-db-context create-arc
-    has-type-relation has-context-relation relation-type create-arc
-    has-context-relation has-context-relation semantic-db-context create-arc ;
+    has-type-relation has-type-relation relation-type create-arc drop
+    has-type-relation semantic-db-context context-type create-arc drop
+    has-context-relation has-type-relation semantic-db-context create-arc drop
+    has-type-relation has-context-relation relation-type create-arc drop
+    has-context-relation has-context-relation semantic-db-context create-arc drop ;
 
 : init-semantic-db ( -- )
     create-node-table create-arc-table create-bootstrap-nodes create-bootstrap-arcs ;
diff --git a/extra/semantic-db/type/type.factor b/extra/semantic-db/type/type.factor
new file mode 100644
index 0000000000..be4da4da83
--- /dev/null
+++ b/extra/semantic-db/type/type.factor
@@ -0,0 +1,19 @@
+! Copyright (C) 2008 Alex Chapman
+! See http://factorcode.org/license.txt for BSD license.
+USING: kernel semantic-db ;
+IN: semantic-db.type
+
+: assign-type ( type nid -- arc-id )
+    has-type-relation spin create-arc ;
+
+: create-node-of-type ( type name -- node-id )
+    create-node [ assign-type drop ] keep ;
+
+: select-node-of-type ( type name -- node-id? )
+    ! find a node with the given name, that is the subject of an arc with:
+    !     relation = has-type-relation
+    !     object = type
+    ;
+
+: ensure-node-of-type ( type name -- node-id )
+    2dup select-node-of-type [ 2nip ] [ create-node-of-type ] if* ;