diff --git a/extra/alarms/alarms-docs.factor b/extra/alarms/alarms-docs.factor
index b609878c77..fcb2de8b6b 100755
--- a/extra/alarms/alarms-docs.factor
+++ b/extra/alarms/alarms-docs.factor
@@ -5,11 +5,11 @@ HELP: alarm
 { $class-description "An alarm. Cancel passed to " { $link cancel-alarm } "." } ;
 
 HELP: add-alarm
-{ $values { "quot" quotation } { "time" timestamp } { "frequency" "a " { $link dt } " or " { $link f } } { "alarm" alarm } }
+{ $values { "quot" quotation } { "time" timestamp } { "frequency" "a " { $link duration } " or " { $link f } } { "alarm" alarm } }
 { $description "Creates and registers an alarm. If " { $snippet "frequency" } " is " { $link f } ", this will be a one-time alarm, otherwise it will fire with the given frequency. The quotation will be called from the alarm thread." } ;
 
 HELP: later
-{ $values { "quot" quotation } { "time" dt } { "alarm" alarm } }
+{ $values { "quot" quotation } { "time" duration } { "alarm" alarm } }
 { $description "Creates and registers an alarm which calls the quotation once at " { $snippet "time" } { $link from-now } "." } ;
 
 HELP: cancel-alarm
diff --git a/extra/alarms/alarms.factor b/extra/alarms/alarms.factor
index 651744d07f..a50e1817e1 100755
--- a/extra/alarms/alarms.factor
+++ b/extra/alarms/alarms.factor
@@ -16,7 +16,7 @@ SYMBOL: alarm-thread
     alarm-thread get-global interrupt ;
 
 : check-alarm
-    dup dt? over not or [ "Not a dt" throw ] unless
+    dup duration? over not or [ "Not a duration" throw ] unless
     over timestamp? [ "Not a timestamp" throw ] unless
     pick callable? [ "Not a quotation" throw ] unless ; inline
 
diff --git a/extra/calendar/calendar.factor b/extra/calendar/calendar.factor
index 7bd655b002..044553067b 100755
--- a/extra/calendar/calendar.factor
+++ b/extra/calendar/calendar.factor
@@ -255,12 +255,12 @@ M: timestamp <=> ( ts1 ts2 -- n )
 : now ( -- timestamp ) gmt >local-time ;
 
 : before ( dt -- -dt )
-    [ year>> neg ] keep
-    [ month>> neg ] keep
-    [ day>> neg ] keep
-    [ hour>> neg ] keep
+    [ year>>   neg ] keep
+    [ month>>  neg ] keep
+    [ day>>    neg ] keep
+    [ hour>>   neg ] keep
     [ minute>> neg ] keep
-    [ second>> neg ] keep
+      second>> neg
     <duration> ;
 
 : from-now ( dt -- timestamp ) now swap time+ ;
diff --git a/extra/concurrency/semaphores/semaphores-docs.factor b/extra/concurrency/semaphores/semaphores-docs.factor
index 7f8b9b017a..76a87f2077 100755
--- a/extra/concurrency/semaphores/semaphores-docs.factor
+++ b/extra/concurrency/semaphores/semaphores-docs.factor
@@ -9,7 +9,7 @@ HELP: <semaphore>
 { $description "Creates a counting semaphore with the specified initial count." } ;
 
 HELP: acquire-timeout
-{ $values { "semaphore" semaphore } { "timeout" "a " { $link dt } " or " { $link f } } { "value" object } }
+{ $values { "semaphore" semaphore } { "timeout" "a " { $link duration } " or " { $link f } } { "value" object } }
 { $description "If the semaphore has a non-zero count, decrements it and returns immediately. Otherwise, if the timeout is " { $link f } ", waits indefinitely for the semaphore to be released. If the timeout is not " { $link f } ", waits a certain period of time, and if the semaphore still has not been released, throws an error." }
 { $errors "Throws an error if the timeout expires before the semaphore is released." } ;
 
@@ -22,7 +22,7 @@ HELP: release
 { $description "Increments a semaphore's count. If the count was previously zero, any threads waiting on the semaphore are woken up." } ;
 
 HELP: with-semaphore-timeout
-{ $values { "semaphore" semaphore } { "timeout" "a " { $link dt } " or " { $link f } } { "quot" quotation } }
+{ $values { "semaphore" semaphore } { "timeout" "a " { $link duration } " or " { $link f } } { "quot" quotation } }
 { $description "Calls the quotation with the semaphore held." } ;
 
 HELP: with-semaphore
diff --git a/extra/io/launcher/launcher-docs.factor b/extra/io/launcher/launcher-docs.factor
index 48b2a01b7d..96639dee87 100755
--- a/extra/io/launcher/launcher-docs.factor
+++ b/extra/io/launcher/launcher-docs.factor
@@ -78,7 +78,7 @@ $nl
 "This is used in situations where you want a spawn child process with some overridden environment variables." } ;
 
 HELP: +timeout+
-{ $description "Launch descriptor key. If set to a " { $link dt } ", specifies a maximum running time for the process. If the process runs longer than this time, it will be killed." } ;
+{ $description "Launch descriptor key. If set to a " { $link duration } ", specifies a maximum running time for the process. If the process runs longer than this time, it will be killed." } ;
 
 HELP: default-descriptor
 { $description "Association storing default values for launch descriptor keys." } ;
diff --git a/extra/io/paths/paths.factor b/extra/io/paths/paths.factor
index 8980eacc3d..fae07643d5 100755
--- a/extra/io/paths/paths.factor
+++ b/extra/io/paths/paths.factor
@@ -34,19 +34,17 @@ TUPLE: directory-iterator path bfs queue ;
         drop r> r> r> 3drop f
     ] if ; inline
 
-: prepare-find-file ( path bfs? quot -- iter quot' )
-    >r <directory-iterator> r> [ keep and ] curry ; inline
-
 : find-file ( path bfs? quot -- path/f )
-    prepare-find-file iterate-directory ;
+    >r <directory-iterator> r>
+    [ keep and ] curry iterate-directory ; inline
+
+: each-file ( path bfs? quot -- )
+    >r <directory-iterator> r>
+    [ f ] compose iterate-directory drop ; inline
 
 : find-all-files ( path bfs? quot -- paths )
-    prepare-find-file V{ } clone [
-        [ over [ push ] [ 2drop ] if f ] curry compose
-        iterate-directory
-        drop
-    ] keep ; inline
+    >r <directory-iterator> r>
+    pusher >r iterate-directory drop r> ; inline
 
 : recursive-directory ( path bfs? -- paths )
-    <directory-iterator>
-    [ dup next-file dup ] [ ] [ drop ] unfold nip ;
+    [ ] accumulator >r each-file r> ;
diff --git a/extra/io/timeouts/timeouts-docs.factor b/extra/io/timeouts/timeouts-docs.factor
index 347c57a0d6..df7e1389cc 100755
--- a/extra/io/timeouts/timeouts-docs.factor
+++ b/extra/io/timeouts/timeouts-docs.factor
@@ -2,11 +2,11 @@ IN: io.timeouts
 USING: help.markup help.syntax math kernel calendar ;
 
 HELP: timeout
-{ $values { "obj" object } { "dt/f" "a " { $link dt } " or " { $link f } } }
+{ $values { "obj" object } { "dt/f" "a " { $link duration } " or " { $link f } } }
 { $contract "Outputs an object's timeout." } ;
 
 HELP: set-timeout
-{ $values { "dt/f" "a " { $link dt } " or " { $link f } } { "obj" object } }
+{ $values { "dt/f" "a " { $link duration } " or " { $link f } } { "obj" object } }
 { $contract "Sets an object's timeout." } ;
 
 HELP: timed-out
diff --git a/extra/models/models-docs.factor b/extra/models/models-docs.factor
index ce86905b9f..d514a539aa 100755
--- a/extra/models/models-docs.factor
+++ b/extra/models/models-docs.factor
@@ -153,7 +153,7 @@ HELP: delay
 } ;
 
 HELP: <delay>
-{ $values { "model" model } { "timeout" dt } { "delay" delay } }
+{ $values { "model" model } { "timeout" duration } { "delay" delay } }
 { $description "Creates a new instance of " { $link delay } ". The timeout must elapse from the time the underlying model last changed to when the delay model value is changed and its connections are notified." }
 { $examples "See the example in the documentation for " { $link delay } "." } ;