diff --git a/hash/md5.cpp b/hash/md5.cpp
index cc62ebb..c121353 100644
--- a/hash/md5.cpp
+++ b/hash/md5.cpp
@@ -9,7 +9,7 @@
 #include "md5.hpp"
 
 #include <cruft/util/std.hpp>
-#include <cruft/util/iterator.hpp>
+#include <cruft/util/iterator/transform.hpp>
 #include <cruft/util/bitwise.hpp>
 #include <cruft/util/debug.hpp>
 
@@ -109,7 +109,7 @@ MD5::operator() (
 
     // note we pass in a windowed view of the state block, not the whole
     // thing.
-    cruft::transform_by_block (
+    cruft::iterator::transform_by_block (
         cruft::view {X.b},
         [&,this] (auto) { ABCD = transform (ABCD, X.w); },
         data_a, data_b, data_c
diff --git a/hash/sha1.cpp b/hash/sha1.cpp
index 33053e0..8ad2f8c 100644
--- a/hash/sha1.cpp
+++ b/hash/sha1.cpp
@@ -8,11 +8,11 @@
 
 #include "sha1.hpp"
 
-#include <cruft/util/iterator.hpp>
 #include <cruft/util/bitwise.hpp>
+#include <cruft/util/cast.hpp>
 #include <cruft/util/debug.hpp>
 #include <cruft/util/endian.hpp>
-#include <cruft/util/cast.hpp>
+#include <cruft/util/iterator/transform.hpp>
 
 #include <algorithm>
 #include <cstdint>
@@ -130,7 +130,7 @@ SHA1::operator() (
     H.w = INITIAL_H;
 
     /* UPDATE */
-    transform_by_block (
+    cruft::iterator::transform_by_block (
         cruft::view {state.c.data (), BLOCK_BYTES },
         [&] (auto) { process (H.w, state.W); },
         data_a, data_b