diff --git a/basis/cpu/arm/assembler/tags.txt b/basis/cpu/arm/assembler/tags.txt
deleted file mode 100644
index 6bf68304bb..0000000000
--- a/basis/cpu/arm/assembler/tags.txt
+++ /dev/null
@@ -1 +0,0 @@
-unportable
diff --git a/core/sequences/sequences-docs.factor b/core/sequences/sequences-docs.factor
index 97679821ea..8851628b21 100755
--- a/core/sequences/sequences-docs.factor
+++ b/core/sequences/sequences-docs.factor
@@ -1630,6 +1630,7 @@ ARTICLE: "sequences-destructive" "Destructive operations"
 "Other destructive words:"
 { $subsections
     reverse!
+    append!
     push-all
     move
     exchange
diff --git a/core/sequences/sequences-tests.factor b/core/sequences/sequences-tests.factor
index 58e61cc94c..dc99542da8 100644
--- a/core/sequences/sequences-tests.factor
+++ b/core/sequences/sequences-tests.factor
@@ -24,6 +24,12 @@ IN: sequences.tests
 [ 5040 { 1 1 2 6 24 120 720 } ]
 [ { 1 2 3 4 5 6 7 } 1 [ * ] accumulate ] unit-test
 
+[ 5040 { 1 1 2 6 24 120 720 } ]
+[ { 1 2 3 4 5 6 7 } 1 [ * ] accumulate! ] unit-test
+
+[ t ]
+[ { 1 2 3 4 5 6 7 } dup 1 [ * ] accumulate! nip eq? ] unit-test
+
 [ f f ] [ [ ] [ ] find ] unit-test
 [ 0 1 ] [ [ 1 ] [ ] find ] unit-test
 [ 1 "world" ] [ [ "hello" "world" ] [ "world" = ] find ] unit-test