diff --git a/basis/tools/deploy/shaker/strip-debugger.factor b/basis/tools/deploy/shaker/strip-debugger.factor
index 121891b563..ec4039a9e7 100644
--- a/basis/tools/deploy/shaker/strip-debugger.factor
+++ b/basis/tools/deploy/shaker/strip-debugger.factor
@@ -1,14 +1,6 @@
-USING: compiler.units continuations kernel namespaces
-threads.private words vocabs tools.deploy.shaker ;
+USING: namespaces tools.deploy.shaker ;
 IN: debugger
 
 : error. ( error -- ) original-error get die-with2 ;
 
 : print-error ( error -- ) error. ;
-
-"threads" vocab [
-    [
-        "error-in-thread" "threads" lookup
-        [ [ drop error. ] define ] [ f "combination" set-word-prop ] bi
-    ] with-compilation-unit
-] when
diff --git a/basis/tools/deploy/shaker/strip-ui-error-hook.factor b/basis/tools/deploy/shaker/strip-ui-error-hook.factor
index 0664dc5e8e..378bc7e27a 100644
--- a/basis/tools/deploy/shaker/strip-ui-error-hook.factor
+++ b/basis/tools/deploy/shaker/strip-ui-error-hook.factor
@@ -1,7 +1,11 @@
-USING: namespaces tools.deploy.config fry sequences system kernel ui ui.gadgets.worlds ;
+USING: continuations namespaces sequences kernel ui
+ui.gadgets.worlds ;
 
-deploy-name get "Factor" or '[
-    _ " encountered an error." append
+[
+    "Error"
     "The application encountered an error it cannot recover from and will now exit."
     system-alert die
-] ui-error-hook set-global
+]
+[ ui-error-hook set-global ]
+[ callback-error-hook set-global ]
+[ [ drop ] prepose thread-error-hook set-global ] tri
diff --git a/basis/ui/debugger/debugger.factor b/basis/ui/debugger/debugger.factor
index e2c8b06bdd..e0abfe05be 100644
--- a/basis/ui/debugger/debugger.factor
+++ b/basis/ui/debugger/debugger.factor
@@ -1,16 +1,20 @@
-! Copyright (C) 2006, 2009 Slava Pestov.
+! Copyright (C) 2006, 2011 Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: accessors debugger io kernel namespaces prettyprint
-ui.gadgets.panes ui.gadgets.worlds ui ;
+USING: accessors continuations debugger io io.streams.string
+kernel namespaces prettyprint ui ui.gadgets.worlds ;
 IN: ui.debugger
 
-: <error-pane> ( error -- pane )
-    <pane> [ [ print-error ] with-pane ] keep ; inline
+: error-alert ( error -- )
+    [ "Error" ] dip [ print-error ] with-string-writer
+    system-alert ;
 
-: error-window ( error -- )
-    <error-pane> "Error" open-window ;
+! ( error -- )
+[ error-alert ] ui-error-hook set-global
 
-[ error-window ] ui-error-hook set-global
+! ( error -- )
+[
+    ui-running? [ dup error-alert ] [ dup print-error ] if die
+] callback-error-hook set-global
 
 M: world-error error.
     "An error occurred while drawing the world " write
diff --git a/basis/ui/tools/debugger/debugger.factor b/basis/ui/tools/debugger/debugger.factor
index a4fda6600e..af987d7dd0 100644
--- a/basis/ui/tools/debugger/debugger.factor
+++ b/basis/ui/tools/debugger/debugger.factor
@@ -1,13 +1,14 @@
-! Copyright (C) 2006, 2009 Slava Pestov.
+! Copyright (C) 2006, 2011 Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: accessors arrays hashtables io kernel math models
-colors.constants namespaces sequences words continuations debugger
-prettyprint help editors fonts ui ui.commands ui.gestures ui.gadgets
-ui.pens.solid ui.gadgets.worlds ui.gadgets.packs ui.gadgets.buttons
-ui.gadgets.labels ui.gadgets.presentations ui.gadgets.viewports
-ui.gadgets.tables ui.gadgets.tracks ui.gadgets.scrollers
-ui.gadgets.borders ui.gadgets.status-bar ui.tools.traceback
-ui.tools.inspector ui.tools.browser ui.debugger ;
+colors.constants namespaces sequences words continuations
+debugger prettyprint help editors fonts ui ui.commands
+ui.debugger ui.gestures ui.gadgets ui.pens.solid
+ui.gadgets.worlds ui.gadgets.packs ui.gadgets.buttons
+ui.gadgets.labels ui.gadgets.presentations ui.gadgets.panes
+ui.gadgets.viewports ui.gadgets.tables ui.gadgets.tracks
+ui.gadgets.scrollers ui.gadgets.borders ui.gadgets.status-bar
+ui.tools.traceback ui.tools.inspector ui.tools.browser ;
 IN: ui.tools.debugger
 
 TUPLE: debugger < track error restarts restart-hook restart-list continuation ;
@@ -26,6 +27,9 @@ M: restart-renderer row-columns
         t >>selection-required?
         t >>single-click? ; inline
 
+: <error-pane> ( error -- pane )
+    <pane> [ [ print-error ] with-pane ] keep ; inline
+
 : <error-display> ( debugger -- gadget )
     [ <filled-pile> ] dip
     [ error>> <error-pane> add-gadget ]
@@ -66,7 +70,7 @@ M: object error-in-debugger? drop f ;
 
 [
     dup error-in-debugger?
-    [ rethrow ] [ error-continuation get debugger-window ] if 
+    [ error-alert ] [ error-continuation get debugger-window ] if
 ] ui-error-hook set-global
 
 debugger "gestures" f {