diff --git a/library/sequences-epilogue.factor b/library/sequences-epilogue.factor
index 23ced82058..4c9a83c4ee 100644
--- a/library/sequences-epilogue.factor
+++ b/library/sequences-epilogue.factor
@@ -20,6 +20,9 @@ UNION: sequence array string sbuf vector ;
 M: object >list ( seq -- list ) dup length 0 rot (>list) ;
 M: general-list >list ( list -- list ) ;
 
+: 2nth ( s s n -- x x ) tuck swap nth >r swap nth r> ;
+
+! Combinators
 GENERIC: (seq-each) ( quot seq -- ) inline
 
 M: object (seq-each) ( quot seq -- )
@@ -36,16 +39,20 @@ M: general-list (seq-each) ( quot seq -- )
     swap [ with ] seq-each 2drop ; inline
 
 GENERIC: (tree-each) ( quot obj -- ) inline
+
 M: object (tree-each) swap call ;
+
 M: cons (tree-each) [ car (tree-each) ] 2keep cdr (tree-each) ;
+
 M: f (tree-each) swap call ;
+
 M: sequence (tree-each) [ swap call ] seq-each-with ;
+
 : tree-each swap (tree-each) ; inline
+
 : tree-each-with ( obj vector quot -- )
     swap [ with ] tree-each 2drop ; inline
 
-: 2nth ( s s n -- x x ) tuck swap nth >r swap nth r> ;
-
 : (seq-2nmap) ( seq1 seq2 i quot -- elt3 )
     pick pick >r >r >r 2nth r> call r> r> swap set-nth ; inline
 
@@ -58,6 +65,7 @@ M: sequence (tree-each) [ swap call ] seq-each-with ;
 : seq-2map ( seq1 seq2 quot -- seq | quot: elt1 elt2 -- elt3 )
     >r clone r> over >r seq-2nmap r> ; inline
 
+! Operations
 : index* ( obj i seq -- n )
     #! The index of the object in the sequence, starting from i.
     2dup length >= [
@@ -74,7 +82,7 @@ M: sequence (tree-each) [ swap call ] seq-each-with ;
     #! Push a value on the end of a sequence.
     dup length swap set-nth ;
 
-: seq-append ( s1 s2 -- )
+: nappend ( s1 s2 -- )
     #! Destructively append s2 to s1.
     [ over push ] seq-each drop ;
 
@@ -88,6 +96,16 @@ M: sequence (tree-each) [ swap call ] seq-each-with ;
 
 : >pop> ( stack -- stack ) dup pop drop ;
 
+: (nreverse) ( seq i -- )
+    #! Swap seq[i] with seq[length-i-1].
+    
+    ;
+
+: nreverse ( seq -- )
+    #! Destructively reverse seq.
+    dup length 2 /i [ 2dup (nreverse) ] repeat drop ;
+
+! Equality testing
 : length= ( seq seq -- ? ) length swap length number= ;
 
 : (sequence=) ( seq seq i -- ? )
diff --git a/library/ui/tiles.factor b/library/ui/tiles.factor
index 67ce1497ce..5f2c549903 100644
--- a/library/ui/tiles.factor
+++ b/library/ui/tiles.factor
@@ -6,7 +6,7 @@ USING: generic kernel math namespaces ;
 ! A tile is a gadget with a caption. Dragging the caption
 ! moves the gadget. The title bar also has buttons for
 ! performing various actions.
-TUPLE: tile original ( size ) ;
+TUPLE: tile original ;
 
 : click-rel ( gadget -- point )
     screen-pos
diff --git a/library/unix/io.factor b/library/unix/io.factor
index 4520c532ef..2a12a46fec 100644
--- a/library/unix/io.factor
+++ b/library/unix/io.factor
@@ -2,7 +2,7 @@
 ! See http://factor.sf.net/license.txt for BSD license.
 IN: io-internals
 USING: errors generic hashtables kernel lists math namespaces
-sequences streams strings threads vectors ;
+sequences stdio streams strings threads vectors ;
 
 ! These let us load the code into a CFactor instance using the
 ! old C-based I/O. They will be removed soon.
@@ -55,7 +55,13 @@ GENERIC: io-task-events ( task -- events )
 ! this with the hash-size call.
 SYMBOL: io-tasks
 
-: init-io ( -- ) global [ <namespace> io-tasks set ] bind ;
+: init-io ( -- )
+    #! Should only be called on startup. Calling this at any
+    #! other time can have unintended consequences.
+    global [
+        <namespace> io-tasks set
+        0 <reader> 1 <writer> <talk-stream> stdio set
+    ] bind ;
 
 : io-task-fd io-task-port port-handle ;
 
diff --git a/library/vectors-epilogue.factor b/library/vectors-epilogue.factor
index b477b2fca4..6030a4fba4 100644
--- a/library/vectors-epilogue.factor
+++ b/library/vectors-epilogue.factor
@@ -16,8 +16,8 @@ IN: vectors
 
 : vector-append ( v1 v2 -- vec )
     over length over length + <vector>
-    [ rot seq-append ] keep
-    [ swap seq-append ] keep ;
+    [ rot nappend ] keep
+    [ swap nappend ] keep ;
 
 : vector-project ( n quot -- vector )
     #! Execute the quotation n times, passing the loop counter