diff --git a/.github/workflows/gen_docs.yml b/.github/workflows/gen_docs.yml
index f3368b4..bab0fc8 100644
--- a/.github/workflows/gen_docs.yml
+++ b/.github/workflows/gen_docs.yml
@@ -18,7 +18,7 @@ jobs:
       - name: checkout
         uses: actions/checkout@v4
       - name: run-doxygen
-        uses: mattnotmitt/doxygen-action@v1.9.8
+        uses: mattnotmitt/doxygen-action@v1.12.0
         with:
           working-directory: doc
       - name: deploy-pages
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e217730..149eacf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-# Copyright (c) 2024 by Cliff Green
+# Copyright (c) 2024-2025 by Cliff Green
 #
 # https://github.com/connectivecpp/binary-serialize
 #
diff --git a/cmake/download_cpm.cmake b/cmake/download_cpm.cmake
index b4e123b..dd69ebe 100644
--- a/cmake/download_cpm.cmake
+++ b/cmake/download_cpm.cmake
@@ -4,7 +4,7 @@
 
 file(
   DOWNLOAD
-  https://github.com/cpm-cmake/CPM.cmake/releases/download/v0.39.0/CPM.cmake
+  https://github.com/cpm-cmake/CPM.cmake/releases/download/v0.40.0/CPM.cmake
   ${CMAKE_CURRENT_BINARY_DIR}/cmake/CPM.cmake
 )
 include(${CMAKE_CURRENT_BINARY_DIR}/cmake/CPM.cmake)
diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt
index f0aed5c..57da68f 100644
--- a/example/CMakeLists.txt
+++ b/example/CMakeLists.txt
@@ -1,4 +1,4 @@
-# Copyright (c) 2024 by Cliff Green
+# Copyright (c) 2024-2025 by Cliff Green
 #
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
diff --git a/example/binary_serialize_example.cpp b/example/binary_serialize_example.cpp
index 5dc62f3..28e133e 100644
--- a/example/binary_serialize_example.cpp
+++ b/example/binary_serialize_example.cpp
@@ -4,7 +4,7 @@
  * 
  * @author Cliff Green
  * 
- * @copyright (c) 2024 by Cliff Green
+ * @copyright (c) 2024-2025 by Cliff Green
  *
  * Distributed under the Boost Software License, Version 1.0. 
  * (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index b459aae..555b0d7 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -1,4 +1,4 @@
-# Copyright (c) 2024 by Cliff Green
+# Copyright (c) 2024-2025 by Cliff Green
 #
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
@@ -12,7 +12,7 @@ project ( binary_serialize_test LANGUAGES CXX )
 include ( ../cmake/download_cpm.cmake )
 
 CPMAddPackage ( "gh:catchorg/Catch2@3.8.0" )
-CPMAddPackage ( "gh:connectivecpp/utility-rack@1.0.4" )
+CPMAddPackage ( "gh:connectivecpp/utility-rack@1.0.5" )
 
 set ( test_app_names byteswap_test
                      extract_append_test
diff --git a/test/binary_serialize_test.cpp b/test/binary_serialize_test.cpp
index f6f38be..6e18a18 100644
--- a/test/binary_serialize_test.cpp
+++ b/test/binary_serialize_test.cpp
@@ -5,7 +5,7 @@
  *
  * @author Cliff Green
  *
- * @copyright (c) 2019-2024 by Cliff Green
+ * @copyright (c) 2019-2025 by Cliff Green
  *
  * Distributed under the Boost Software License, Version 1.0. 
  * (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/test/extract_append_test.cpp b/test/extract_append_test.cpp
index ffb1293..bbd0dc6 100644
--- a/test/extract_append_test.cpp
+++ b/test/extract_append_test.cpp
@@ -4,7 +4,7 @@
  *
  * @author Cliff Green, Roxanne Agerone
  *
- * @copyright (c) 2019-2024 by Cliff Green, Roxanne Agerone
+ * @copyright (c) 2019-2025 by Cliff Green, Roxanne Agerone
  *
  * Distributed under the Boost Software License, Version 1.0. 
  * (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
@@ -16,10 +16,10 @@
 
 #include <cstddef> // std::byte
 #include <cstdint> // std::uint32_t, etc
+#include <ranges> // std::views::iota
 
 #include "serialize/extract_append.hpp"
 
-#include "utility/repeat.hpp"
 #include "utility/byte_array.hpp"
 
 constexpr std::uint32_t val1 = 0xDDCCBBAA;
@@ -65,8 +65,9 @@ TEST_CASE ( "Append values into a buffer", "[append_val]" ) {
     REQUIRE(chops::append_val<std::endian::big>(ptr, val4) == 8u); ptr += sizeof(val4);
     REQUIRE(chops::append_val<std::endian::big>(ptr, val5) == 4u); ptr += sizeof(val5);
     REQUIRE(chops::append_val<std::endian::big>(ptr, val6) == 1u);
-    chops::repeat(arr_sz, [&buf] (int i) { 
-        REQUIRE (std::to_integer<int>(buf[i]) == std::to_integer<int>(net_buf_big[i])); } );
+    for (int i : std::views::iota(0, arr_sz)) {
+      REQUIRE (std::to_integer<int>(buf[i]) == std::to_integer<int>(net_buf_big[i]));
+    }
   }
   SECTION ("Append_val with multiple values, little endian") {
     std::byte* ptr = buf;
@@ -76,8 +77,9 @@ TEST_CASE ( "Append values into a buffer", "[append_val]" ) {
     REQUIRE(chops::append_val<std::endian::little>(ptr, val4) == 8u); ptr += sizeof(val4);
     REQUIRE(chops::append_val<std::endian::little>(ptr, val5) == 4u); ptr += sizeof(val5);
     REQUIRE(chops::append_val<std::endian::little>(ptr, val6) == 1u);
-    chops::repeat(arr_sz, [&buf] (int i) { 
-        REQUIRE (std::to_integer<int>(buf[i]) == std::to_integer<int>(net_buf_little[i])); } );
+    for (int i : std::views::iota(0, arr_sz)) {
+      REQUIRE (std::to_integer<int>(buf[i]) == std::to_integer<int>(net_buf_little[i]));
+    }
   }
 }