diff --git a/extra/darcs-ui b/extra/darcs-ui
index e2554b2eba..8a2deafe64 160000
--- a/extra/darcs-ui
+++ b/extra/darcs-ui
@@ -1 +1 @@
-Subproject commit e2554b2ebae120bbd315ccbca8aa833bc8cb830e
+Subproject commit 8a2deafe64cba990453126befbbbf2eed0ffd8f8
diff --git a/extra/recipes/recipes.factor b/extra/recipes/recipes.factor
index 88595b551a..125f187e7f 100644
--- a/extra/recipes/recipes.factor
+++ b/extra/recipes/recipes.factor
@@ -27,7 +27,7 @@ STORED-TUPLE: recipe { title { VARCHAR 100 } } { votes INTEGER } { txt TEXT } {
      ] <vbox> ,
   ] <frp-book*> { 350 245 } >>pref-dim ;
   
-:: recipe-browser ( -- ) [
+:: recipe-browser ( -- ) [ [
     interface
       <frp-table*> :> tbl
       "okay" <frp-border-button> BUTTON -> :> ok
@@ -56,6 +56,6 @@ STORED-TUPLE: recipe { title { VARCHAR 100 } } { votes INTEGER } { txt TEXT } {
       [ [ 1 ] <$ ]
       [ quot ok <updates> #1 [ call( recipe -- ) 0 ] 2fmap-& ] bi
       2array <merge> 0 <basic> <switch> >>model
-   ] with-interface "recipes" open-window ;
+   ] with-interface "recipes" open-window ] with-ui ;
 
 MAIN: recipe-browser
\ No newline at end of file
diff --git a/extra/ui/frp/signals/signals.factor b/extra/ui/frp/signals/signals.factor
index b5389f7bb9..4db526dbb3 100644
--- a/extra/ui/frp/signals/signals.factor
+++ b/extra/ui/frp/signals/signals.factor
@@ -30,6 +30,7 @@ IN: ui.frp.signals
 TUPLE: basic-model < multi-model ;
 M: basic-model (model-changed) [ value>> ] dip set-model ;
 : <merge> ( models -- signal ) basic-model <multi-model> ;
+: <2merge> ( model1 model2 -- signal ) 2array <merge> ;
 : <basic> ( value -- signal ) basic-model new-model ;
 
 TUPLE: filter-model < multi-model quot ;
@@ -37,11 +38,18 @@ M: filter-model (model-changed) [ value>> ] dip 2dup quot>> call( a -- ? )
    [ set-model ] [ 2drop ] if ;
 : <filter> ( model quot -- filter-signal ) [ 1array filter-model <multi-model> ] dip >>quot ;
 
-TUPLE: fold-model < multi-model quot ;
-M: fold-model (model-changed) [ [ value>> ] [ [ value>> ] [ quot>> ] bi ] bi*
-   call( val oldval -- newval ) ] keep set-model ;
-: <fold> ( model oldval quot -- signal ) rot 1array fold-model <multi-model> swap >>quot
+TUPLE: fold-model < multi-model quot base values ;
+M: fold-model (model-changed) 2dup base>> =
+    [ [ [ value>> ] [ [ values>> ] [ quot>> ] bi ] bi* swapd reduce* ] keep set-model ]
+    [ [ [ value>> ] [ values>> ] bi* push ]
+      [ [ [ value>> ] [ [ value>> ] [ quot>> ] bi ] bi* call( val oldval -- newval ) ] keep set-model ] 2bi
+    ] if ;
+M: fold-model model-activated drop ;
+: new-fold-model ( deps -- model ) fold-model <multi-model> V{ } clone >>values ;
+: <fold> ( model oldval quot -- signal ) rot 1array new-fold-model swap >>quot
    swap >>value ;
+: <fold*> ( model oldmodel quot -- signal ) over [ [ 2array new-fold-model ] dip >>quot ]
+    dip [ >>base ] [ value>> >>value ] bi ;
 
 TUPLE: updater-model < multi-model values updates ;
 M: updater-model (model-changed) tuck updates>> =
@@ -105,4 +113,7 @@ PRIVATE>
 M: model >>= [ swap <action> ] curry ;
 M: model fmap <mapped> ;
 USE: ui.frp.functors
-FMAPS: $> <$ fmap FOR & | product ;
\ No newline at end of file
+FMAPS: $> <$ fmap FOR & | product ;
+
+! only used in construction
+: with-self ( quot: ( model -- model ) -- model ) [ f <basic> dup ] dip call swap [ add-dependency ] keep ; inline
\ No newline at end of file