diff --git a/extra/crypto/common/common.factor b/extra/crypto/common/common.factor
index f0129772b0..b9f1d43784 100644
--- a/extra/crypto/common/common.factor
+++ b/extra/crypto/common/common.factor
@@ -2,7 +2,7 @@ USING: arrays kernel io io.binary sbufs splitting strings sequences
 namespaces math math.parser parser hints math.bitfields.lib ;
 IN: crypto.common
 
-: w+ ( int int -- int ) + 32-bit ; inline
+: w+ ( int int -- int ) + 32 bits ; inline
 
 : (nth-int) ( string n -- int )
     2 shift dup 4 + rot <slice> ; inline
diff --git a/extra/crypto/sha1/sha1.factor b/extra/crypto/sha1/sha1.factor
index 7e8677a117..d054eda31b 100755
--- a/extra/crypto/sha1/sha1.factor
+++ b/extra/crypto/sha1/sha1.factor
@@ -66,7 +66,7 @@ SYMBOLS: h0 h1 h2 h3 h4 A B C D E w K ;
         K get nth ,
         A get 5 bitroll-32 ,
         E get ,
-    ] { } make sum 32-bit ; inline
+    ] { } make sum 32 bits ; inline
 
 : set-vars ( temp -- )
     ! E = D;  D = C;  C = S^30(B);  B = A; A = TEMP;
diff --git a/extra/crypto/sha2/sha2.factor b/extra/crypto/sha2/sha2.factor
index f555de8b08..0acc5c1388 100755
--- a/extra/crypto/sha2/sha2.factor
+++ b/extra/crypto/sha2/sha2.factor
@@ -4,7 +4,7 @@ IN: crypto.sha2
 
 <PRIVATE
 
-SYMBOLS: vars M K H S0 S1 process-M word-size block-size >word ;
+SYMBOLS: vars M K H S0 S1 process-M word-size block-size ;
 
 : a 0 ; inline
 : b 1 ; inline
@@ -124,7 +124,6 @@ PRIVATE>
         initial-H-256 H set
         4 word-size set
         64 block-size set
-        \ 32-bit >word set
         byte-array>sha2
     ] with-scope ;
 
diff --git a/extra/math/bitfields/lib/lib-docs.factor b/extra/math/bitfields/lib/lib-docs.factor
new file mode 100644
index 0000000000..bfbe9eaded
--- /dev/null
+++ b/extra/math/bitfields/lib/lib-docs.factor
@@ -0,0 +1,16 @@
+USING: help.markup help.syntax kernel math sequences ;
+IN: math.bitfields.lib
+
+HELP: bits 
+{ $values { "m" integer } { "n" integer } { "m'" integer } }
+{ $description "Keep only n bits from the integer m." }
+{ $example "USING: math.bitfields.lib prettyprint ;" "HEX: 123abcdef 16 bits .h" "cdef" } ;
+
+HELP: bitroll
+{ $values { "x" "an integer (input)" } { "s" "an integer (shift)" } { "w" "an integer (wrap)" } { "y" integer } }
+{ $description "Roll n by s bits to the left, wrapping around after w bits." }
+{ $examples
+    { $example "USING: math.bitfields.lib prettyprint ;" "1 -1 32 bitroll .b" "10000000000000000000000000000000" }
+    { $example "USING: math.bitfields.lib prettyprint ;" "HEX: ffff0000 8 32 bitroll .h" "ff0000ff" }
+} ;
+
diff --git a/extra/math/bitfields/lib/lib-tests.factor b/extra/math/bitfields/lib/lib-tests.factor
new file mode 100644
index 0000000000..c002240e69
--- /dev/null
+++ b/extra/math/bitfields/lib/lib-tests.factor
@@ -0,0 +1,14 @@
+USING: math.bitfields.lib tools.test ;
+IN: math.bitfields.lib.test
+
+[ 0 ] [ 1 0 0 bitroll ] unit-test
+[ 1 ] [ 1 0 1 bitroll ] unit-test
+[ 1 ] [ 1 1 1 bitroll ] unit-test
+[ 1 ] [ 1 0 2 bitroll ] unit-test
+[ 1 ] [ 1 0 1 bitroll ] unit-test
+[ 1 ] [ 1 20 2 bitroll ] unit-test
+[ 1 ] [ 1 8 8 bitroll ] unit-test
+[ 1 ] [ 1 -8 8 bitroll ] unit-test
+[ 1 ] [ 1 -32 8 bitroll ] unit-test
+[ 128 ] [ 1 -1 8 bitroll ] unit-test
+[ 8 ] [ 1 3 32 bitroll ] unit-test
diff --git a/extra/math/bitfields/lib/lib.factor b/extra/math/bitfields/lib/lib.factor
new file mode 100644
index 0000000000..4a8f3835ca
--- /dev/null
+++ b/extra/math/bitfields/lib/lib.factor
@@ -0,0 +1,31 @@
+USING: hints kernel math ;
+IN: math.bitfields.lib
+
+: clear-bit ( x n -- y ) 2^ bitnot bitand ; foldable
+: set-bit ( x n -- y ) 2^ bitor ; foldable
+: bit-clear? ( x n -- ? ) 2^ bitand zero? ; foldable
+: bit-set? ( x n -- ? ) bit-clear? not ; foldable
+: unmask ( x n -- ? ) bitnot bitand ; foldable
+: unmask? ( x n -- ? ) unmask 0 > ; foldable
+: mask ( x n -- ? ) bitand ; foldable
+: mask? ( x n -- ? ) mask 0 > ; foldable
+: wrap ( m n -- m' ) 1- bitand ; foldable
+: bits ( m n -- m' ) 2^ wrap ; inline
+: mask-bit ( m n -- m' ) 1- 2^ mask ; inline
+
+: shift-mod ( n s w -- n )
+    >r shift r> 2^ wrap ; inline
+
+: bitroll ( x s w -- y )
+     [ wrap ] keep
+     [ shift-mod ] 3keep
+     [ - ] keep shift-mod bitor ; inline
+
+: bitroll-32 ( n s -- n' ) 32 bitroll ;
+
+HINTS: bitroll-32 bignum fixnum ;
+
+: bitroll-64 ( n s -- n' ) 64 bitroll ;
+
+HINTS: bitroll-64 bignum fixnum ;
+