diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 358c5f14..29ad4424 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -552,6 +552,7 @@ jobs:
             git submodule update --init tools/boostdep
             DEPINST_ARGS+=("$LIBRARY")
             python tools/boostdep/depinst/depinst.py "${DEPINST_ARGS[@]}"
+            python libs/core/tools/setup_boost_with_modules.py # Temporary
             ./bootstrap.sh
             ./b2 headers
             if [ -n "${{matrix.compiler}}" -o -n "$GCC_TOOLCHAIN_ROOT" ]
@@ -661,6 +662,7 @@ jobs:
             rmdir /s /q "..\snapshot"
             git submodule update --init tools/boostdep
             python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" %LIBRARY%
+            python libs/core/tools/setup_boost_with_modules.py # Temporary
             cmd /c bootstrap
             b2 -d0 headers
 
@@ -728,6 +730,7 @@ jobs:
           rm -rf "../snapshot"
           git submodule update --init tools/boostdep
           python tools/boostdep/depinst/depinst.py --git_args "--jobs $GIT_FETCH_JOBS" $LIBRARY
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
 
       - name: Use library with add_subdirectory
         run: |
@@ -795,6 +798,7 @@ jobs:
           rm -rf "../snapshot"
           git submodule update --init tools/boostdep
           python tools/boostdep/depinst/depinst.py --git_args "--jobs $GIT_FETCH_JOBS" $LIBRARY
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
 
       - name: Configure
         run: |
@@ -877,6 +881,7 @@ jobs:
           rm -rf "../snapshot"
           git submodule update --init tools/boostdep
           python tools/boostdep/depinst/depinst.py --git_args "--jobs $GIT_FETCH_JOBS" $LIBRARY
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
 
       - name: Configure
         run: |
@@ -940,6 +945,7 @@ jobs:
           rmdir /s /q "..\snapshot"
           git submodule update --init tools/boostdep
           python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" %LIBRARY%
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
 
       - name: Use library with add_subdirectory (Debug)
         shell: cmd
@@ -1002,6 +1008,7 @@ jobs:
           rmdir /s /q "..\snapshot"
           git submodule update --init tools/boostdep
           python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" %LIBRARY%
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
 
       - name: Configure
         shell: cmd
@@ -1082,6 +1089,7 @@ jobs:
           rmdir /s /q "..\snapshot"
           git submodule update --init tools/boostdep
           python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" %LIBRARY%
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
 
       - name: Configure
         shell: cmd
@@ -1113,3 +1121,349 @@ jobs:
         run: |
           cd boost-root/__build__
           ctest --output-on-failure --no-tests=error -C Release
+
+  posix-cmake-subdir-modules:
+
+
+    runs-on: ubuntu-latest
+    container: ubuntu:26.04
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        run: |
+          export DEBIAN_FRONTEND=noninteractive
+          apt-get update
+          apt-get install -y --no-install-recommends wget ninja-build git ca-certificates python3 python-is-python3 g++-15
+          ./tools/install-cmake.sh
+
+      - name: Setup Boost
+        run: |
+          echo GITHUB_REPOSITORY: $GITHUB_REPOSITORY
+          LIBRARY=${GITHUB_REPOSITORY#*/}
+          echo LIBRARY: $LIBRARY
+          echo "LIBRARY=$LIBRARY" >> $GITHUB_ENV
+          echo GITHUB_BASE_REF: $GITHUB_BASE_REF
+          echo GITHUB_REF: $GITHUB_REF
+          REF=${GITHUB_BASE_REF:-$GITHUB_REF}
+          REF=${REF#refs/heads/}
+          echo REF: $REF
+          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          echo BOOST_BRANCH: $BOOST_BRANCH
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py $LIBRARY
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
+
+      - name: Use library with add_subdirectory
+        run: |
+          cd ../boost-root/libs/$LIBRARY/test/cmake_subdir_test
+          mkdir __build__ && cd __build__
+          cmake \
+            -G Ninja \
+            -DBOOST_USE_MODULES=ON \
+            -DCMAKE_CXX_MODULE_STD=ON \
+            -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=d0edc3af-4c50-42ea-a356-e2862fe7a444 \
+            -DCMAKE_CXX_COMPILER=g++-15 \
+            ..
+          cmake --build .
+          ctest --output-on-failure --no-tests=error
+
+  posix-cmake-install-modules:
+
+    runs-on: ubuntu-latest
+    container: ubuntu:26.04
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        run: |
+          export DEBIAN_FRONTEND=noninteractive
+          apt-get update
+          apt-get install -y --no-install-recommends wget ninja-build git ca-certificates python3 python-is-python3 g++-15
+          ./tools/install-cmake.sh
+
+      - name: Setup Boost
+        run: |
+          echo GITHUB_REPOSITORY: $GITHUB_REPOSITORY
+          LIBRARY=${GITHUB_REPOSITORY#*/}
+          echo LIBRARY: $LIBRARY
+          echo "LIBRARY=$LIBRARY" >> $GITHUB_ENV
+          echo GITHUB_BASE_REF: $GITHUB_BASE_REF
+          echo GITHUB_REF: $GITHUB_REF
+          REF=${GITHUB_BASE_REF:-$GITHUB_REF}
+          REF=${REF#refs/heads/}
+          echo REF: $REF
+          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          echo BOOST_BRANCH: $BOOST_BRANCH
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py $LIBRARY
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
+
+      - name: Configure
+        run: |
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake \
+            -G Ninja \
+            -DBOOST_INCLUDE_LIBRARIES=$LIBRARY \
+            -DCMAKE_INSTALL_PREFIX=~/.local \
+            -DBOOST_USE_MODULES=ON \
+            -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=d0edc3af-4c50-42ea-a356-e2862fe7a444 \
+            -DCMAKE_CXX_COMPILER=g++-15 \
+            ..
+
+      - name: Install
+        run: |
+          cd ../boost-root/__build__
+          cmake --build . --target install
+
+      - name: Use the installed library
+        run: |
+          cd ../boost-root/libs/$LIBRARY/test/cmake_install_test && mkdir __build__ && cd __build__
+          cmake \
+            -G Ninja \
+            -DCMAKE_INSTALL_PREFIX=~/.local \
+            -DCMAKE_CXX_MODULE_STD=ON \
+            -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=d0edc3af-4c50-42ea-a356-e2862fe7a444 \
+            -DCMAKE_CXX_COMPILER=g++-15 \
+            ..
+          cmake --build .
+          ctest --output-on-failure --no-tests=error
+
+  posix-cmake-test-modules:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: "clang-21 Debug"
+            packages: "clang-21 libc++-21-dev"
+            cmake-args: "-DCMAKE_C_COMPILER=clang-21 -DCMAKE_CXX_COMPILER=clang++-21 -DCMAKE_CXX_FLAGS=-stdlib=libc++ -DCMAKE_EXE_LINKER_FLAGS=-stdlib=libc++ -DCMAKE_CXX_STDLIB_MODULES_JSON=/usr/lib/llvm-21/lib/libc++.modules.json -DCMAKE_BUILD_TYPE=Debug"
+          - name: "clang-21 Release"
+            packages: "clang-21 libc++-21-dev"
+            cmake-args: "-DCMAKE_C_COMPILER=clang-21 -DCMAKE_CXX_COMPILER=clang++-21 -DCMAKE_CXX_FLAGS=-stdlib=libc++ -DCMAKE_EXE_LINKER_FLAGS=-stdlib=libc++ -DCMAKE_CXX_STDLIB_MODULES_JSON=/usr/lib/llvm-21/lib/libc++.modules.json -DCMAKE_BUILD_TYPE=Release"
+          - name: "gcc-15 Debug"
+            packages: "g++-15"
+            cmake-args: "-DCMAKE_C_COMPILER=gcc-15 -DCMAKE_CXX_COMPILER=g++-15 -DCMAKE_BUILD_TYPE=Debug"
+
+    name: CMake test modules ${{ matrix.name }}
+
+    runs-on: ubuntu-latest
+    container: ubuntu:26.04
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        run: |
+          export DEBIAN_FRONTEND=noninteractive
+          apt-get update
+          apt-get install -y --no-install-recommends wget ninja-build git ca-certificates python3 python-is-python3 ${{ matrix.packages }}
+          ./tools/install-cmake.sh
+
+      - name: Setup Boost
+        run: |
+          echo GITHUB_REPOSITORY: $GITHUB_REPOSITORY
+          LIBRARY=${GITHUB_REPOSITORY#*/}
+          echo LIBRARY: $LIBRARY
+          echo "LIBRARY=$LIBRARY" >> $GITHUB_ENV
+          echo GITHUB_BASE_REF: $GITHUB_BASE_REF
+          echo GITHUB_REF: $GITHUB_REF
+          REF=${GITHUB_BASE_REF:-$GITHUB_REF}
+          REF=${REF#refs/heads/}
+          echo REF: $REF
+          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          echo BOOST_BRANCH: $BOOST_BRANCH
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py $LIBRARY
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
+
+      - name: Configure
+        run: |
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake \
+            -G Ninja \
+            -DCMAKE_CXX_STANDARD=23 \
+            -DBOOST_INCLUDE_LIBRARIES=$LIBRARY \
+            -DBUILD_TESTING=ON \
+            -DBOOST_USE_MODULES=ON \
+            -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=d0edc3af-4c50-42ea-a356-e2862fe7a444 \
+            ${{ matrix.cmake-args }} \
+            ..
+
+      - name: Build tests
+        run: |
+          cd ../boost-root/__build__
+          cmake --build . --target tests
+
+      - name: Run tests
+        run: |
+          cd ../boost-root/__build__
+          ctest --output-on-failure --no-tests=error
+
+  windows-cmake-subdir-modules:
+    runs-on: windows-2022
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        run: choco install --no-progress ninja
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
+
+      - name: Use library with add_subdirectory
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root/libs/%LIBRARY%/test/cmake_subdir_test
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_USE_MODULES=1 -DCMAKE_CXX_STANDARD=23 -DCMAKE_CXX_MODULE_STD=ON -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=0e5b6991-d74f-4b3d-a41c-cf096e0b2508 -G Ninja ..
+          cmake --build .
+          ctest --output-on-failure --no-tests=error
+
+  windows-cmake-install-modules:
+    runs-on: windows-2022
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        run: choco install --no-progress ninja
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
+
+      - name: Configure
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_INCLUDE_LIBRARIES=%LIBRARY% -DCMAKE_INSTALL_PREFIX=C:/cmake-prefix -DBOOST_USE_MODULES=1 -DCMAKE_CXX_STANDARD=23 -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=0e5b6991-d74f-4b3d-a41c-cf096e0b2508 -G Ninja ..
+
+      - name: Install
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root/__build__
+          cmake --build . --target install
+
+      - name: Use the installed library
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root/libs/%LIBRARY%/test/cmake_install_test && mkdir __build__ && cd __build__
+          cmake -DCMAKE_INSTALL_PREFIX=C:/cmake-prefix -DCMAKE_CXX_STANDARD=23 -DCMAKE_CXX_MODULE_STD=ON -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=0e5b6991-d74f-4b3d-a41c-cf096e0b2508 -G Ninja ..
+          cmake --build .
+          ctest --output-on-failure --no-tests=error
+
+  windows-cmake-test-modules:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - cmake-build-type: Debug
+          - cmake-build-type: Release
+
+    runs-on: windows-2022
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        run: choco install --no-progress ninja
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+          python libs/core/tools/setup_boost_with_modules.py # Temporary
+
+      - name: Configure
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_INCLUDE_LIBRARIES=%LIBRARY% -DBUILD_TESTING=ON -DBOOST_USE_MODULES=1 -DCMAKE_CXX_STANDARD=23 -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=0e5b6991-d74f-4b3d-a41c-cf096e0b2508 -DCMAKE_BUILD_TYPE=${{matrix.cmake-build-type}} -G Ninja  ..
+
+      - name: Build tests
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root/__build__
+          cmake --build . --target tests
+
+      - name: Run tests
+        shell: cmd
+        run: |
+          call "C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvarsall.bat" x64
+          cd ../boost-root/__build__
+          ctest --output-on-failure --no-tests=error
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1b2c5abd..cfe1ff34 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,17 +3,29 @@
 # Distributed under the Boost Software License, Version 1.0.
 # https://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required(VERSION 3.5...3.20)
+cmake_minimum_required(VERSION 3.5...3.31)
 
 project(boost_core VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX)
 
-add_library(boost_core INTERFACE)
-add_library(Boost::core ALIAS boost_core)
+if (BOOST_USE_MODULES)
+  add_library(boost_core STATIC)
+  target_sources(boost_core PUBLIC FILE_SET CXX_MODULES BASE_DIRS modules FILES modules/boost_core.cppm)
+  set(__scope PUBLIC)
+
+  # Enable and propagate C++23, import std, and the modules macro
+  target_compile_features(boost_core PUBLIC cxx_std_23)
+  set_target_properties(boost_core PROPERTIES CXX_MODULE_STD 1)
+  target_compile_definitions(boost_core PUBLIC BOOST_USE_MODULES)
 
-target_include_directories(boost_core INTERFACE include)
+else()
+  add_library(boost_core INTERFACE)
+  set(__scope INTERFACE)
+endif()
 
+add_library(Boost::core ALIAS boost_core)
+target_include_directories(boost_core ${__scope} include)
 target_link_libraries(boost_core
-  INTERFACE
+  ${__scope}
     Boost::assert
     Boost::config
     Boost::throw_exception
diff --git a/appveyor.yml b/appveyor.yml
index 510bd413..7e599633 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -79,6 +79,7 @@ install:
   - git submodule update --init tools/boostdep
   - xcopy /s /e /q %APPVEYOR_BUILD_FOLDER% libs\core\
   - python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" core
+  - python libs/core/tools/setup_boost_with_modules.py # Temporary
   - cmd /c bootstrap
   - b2 -d0 headers
 
diff --git a/include/boost/core/addressof.hpp b/include/boost/core/addressof.hpp
index 5473c36a..b7758017 100644
--- a/include/boost/core/addressof.hpp
+++ b/include/boost/core/addressof.hpp
@@ -14,6 +14,17 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_ADDRESSOF_HPP
 #define BOOST_CORE_ADDRESSOF_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+// RP TODO: BOOST_CORE_HAS_BUILTIN_ADDRESSOF
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 #if defined(BOOST_MSVC_FULL_VER) && BOOST_MSVC_FULL_VER >= 190024215
@@ -33,7 +44,7 @@ Distributed under the Boost Software License, Version 1.0.
 
 namespace boost {
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR inline T*
 addressof(T& o) BOOST_NOEXCEPT
 {
@@ -43,7 +54,7 @@ addressof(T& o) BOOST_NOEXCEPT
 } /* boost */
 #else
 #include <boost/config/workaround.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost {
 namespace detail {
@@ -143,7 +154,7 @@ struct addrof_result {
 
 } /* detail */
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 BOOST_FORCEINLINE typename boost::detail::addrof_result<T[N]>::type
 addressof(T (&o)[N]) BOOST_NOEXCEPT
 {
@@ -152,14 +163,14 @@ addressof(T (&o)[N]) BOOST_NOEXCEPT
 #endif
 
 #if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x564))
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 BOOST_FORCEINLINE
 T (*addressof(T (&o)[N]) BOOST_NOEXCEPT)[N]
 {
    return reinterpret_cast<T(*)[N]>(&o);
 }
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 BOOST_FORCEINLINE
 const T (*addressof(const T (&o)[N]) BOOST_NOEXCEPT)[N]
 {
@@ -250,7 +261,7 @@ addressof(T& o) BOOST_NOEXCEPT
 
 } /* detail */
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 constexpr BOOST_FORCEINLINE T*
 addressof(T& o) BOOST_NOEXCEPT
 {
@@ -265,10 +276,12 @@ addressof(T& o) BOOST_NOEXCEPT
     !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
 namespace boost {
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 const T* addressof(const T&&) = delete;
 
 } /* boost */
 #endif
 
 #endif
+
+#endif
diff --git a/include/boost/core/alignof.hpp b/include/boost/core/alignof.hpp
index 07ff4447..712a65b6 100644
--- a/include/boost/core/alignof.hpp
+++ b/include/boost/core/alignof.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_ALIGNOF_HPP_INCLUDED)
+#  error "Please #include <boost/core/alignof.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_ALIGNOF_HPP_INCLUDED
 #define BOOST_CORE_ALIGNOF_HPP_INCLUDED
 
@@ -12,7 +17,7 @@
 //  https://www.boost.org/LICENSE_1_0.txt
 
 #include <boost/config.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 #if !defined(BOOST_NO_CXX11_ALIGNOF)
 
diff --git a/include/boost/core/alloc_construct.hpp b/include/boost/core/alloc_construct.hpp
index 075d3cb3..294bd518 100644
--- a/include/boost/core/alloc_construct.hpp
+++ b/include/boost/core/alloc_construct.hpp
@@ -8,28 +8,35 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_ALLOC_CONSTRUCT_HPP
 #define BOOST_CORE_ALLOC_CONSTRUCT_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
 /*
 This functionality is now in <boost/core/allocator_access.hpp>.
 */
 #include <boost/core/noinit_adaptor.hpp>
+#include <boost/core/detail/modules.hpp>
 
 namespace boost {
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 alloc_destroy(A& a, T* p)
 {
     boost::allocator_destroy(a, p);
 }
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 alloc_destroy_n(A& a, T* p, std::size_t n)
 {
     boost::allocator_destroy_n(a, p, n);
 }
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 alloc_construct(A& a, T* p)
 {
@@ -38,7 +45,7 @@ alloc_construct(A& a, T* p)
 
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
-template<class A, class T, class U, class... V>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class U, class... V>
 inline void
 alloc_construct(A& a, T* p, U&& u, V&&... v)
 {
@@ -46,7 +53,7 @@ alloc_construct(A& a, T* p, U&& u, V&&... v)
         std::forward<V>(v)...);
 }
 #else
-template<class A, class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class U>
 inline void
 alloc_construct(A& a, T* p, U&& u)
 {
@@ -54,14 +61,14 @@ alloc_construct(A& a, T* p, U&& u)
 }
 #endif
 #else
-template<class A, class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class U>
 inline void
 alloc_construct(A& a, T* p, const U& u)
 {
     boost::allocator_construct(a, p, u);
 }
 
-template<class A, class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class U>
 inline void
 alloc_construct(A& a, T* p, U& u)
 {
@@ -69,21 +76,21 @@ alloc_construct(A& a, T* p, U& u)
 }
 #endif
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 alloc_construct_n(A& a, T* p, std::size_t n)
 {
     boost::allocator_construct_n(a, p, n);
 }
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 alloc_construct_n(A& a, T* p, std::size_t n, const T* l, std::size_t m)
 {
     boost::allocator_construct_n(a, p, n, l, m);
 }
 
-template<class A, class T, class I>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class I>
 inline void
 alloc_construct_n(A& a, T* p, std::size_t n, I b)
 {
@@ -93,3 +100,5 @@ alloc_construct_n(A& a, T* p, std::size_t n, I b)
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/allocator_access.hpp b/include/boost/core/allocator_access.hpp
index 0f0ed325..2981323e 100644
--- a/include/boost/core/allocator_access.hpp
+++ b/include/boost/core/allocator_access.hpp
@@ -8,15 +8,22 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_ALLOCATOR_ACCESS_HPP
 #define BOOST_CORE_ALLOCATOR_ACCESS_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 #include <boost/core/pointer_traits.hpp>
-#include <limits>
-#include <new>
+#include <boost/config/std/limits.hpp>
+#include <boost/config/std/new.hpp>
 #if !defined(BOOST_NO_CXX11_ALLOCATOR)
-#include <type_traits>
+#include <boost/config/std/type_traits.hpp>
 #endif
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-#include <utility>
+#include <boost/config/std/utility.hpp>
 #endif
 
 #if defined(BOOST_GCC_VERSION) && (BOOST_GCC_VERSION >= 40300)
@@ -58,7 +65,7 @@ _STL_DISABLE_DEPRECATED_WARNING
 
 namespace boost {
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_value_type {
     typedef typename A::value_type type;
 };
@@ -83,7 +90,7 @@ struct alloc_ptr<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_pointer {
     typedef typename detail::alloc_ptr<A>::type type;
 };
@@ -105,7 +112,7 @@ struct alloc_const_ptr<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_const_pointer {
     typedef typename detail::alloc_const_ptr<A>::type type;
 };
@@ -151,7 +158,7 @@ struct alloc_rebind<A, T,
 
 } /* detail */
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 struct allocator_rebind {
     typedef typename detail::alloc_rebind<A, T>::type type;
 };
@@ -173,7 +180,7 @@ struct alloc_void_ptr<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_void_pointer {
     typedef typename detail::alloc_void_ptr<A>::type type;
 };
@@ -195,7 +202,7 @@ struct alloc_const_void_ptr<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_const_void_pointer {
     typedef typename detail::alloc_const_void_ptr<A>::type type;
 };
@@ -216,7 +223,7 @@ struct alloc_diff_type<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_difference_type {
     typedef typename detail::alloc_diff_type<A>::type type;
 };
@@ -244,7 +251,7 @@ struct alloc_size_type<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_size_type {
     typedef typename detail::alloc_size_type<A>::type type;
 };
@@ -290,7 +297,7 @@ struct alloc_pocca<A,
 
 } /* detail */
 
-template<class A, class = void>
+BOOST_CORE_MODULE_EXPORT template<class A, class = void>
 struct allocator_propagate_on_container_copy_assignment {
     typedef typename detail::alloc_pocca<A>::type type;
 };
@@ -311,7 +318,7 @@ struct alloc_pocma<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_propagate_on_container_move_assignment {
     typedef typename detail::alloc_pocma<A>::type type;
 };
@@ -331,7 +338,7 @@ struct alloc_pocs<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_propagate_on_container_swap {
     typedef typename detail::alloc_pocs<A>::type type;
 };
@@ -363,19 +370,19 @@ struct alloc_equal<A,
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_is_always_equal {
     typedef typename detail::alloc_equal<A>::type type;
 };
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename allocator_pointer<A>::type
 allocator_allocate(A& a, typename allocator_size_type<A>::type n)
 {
     return a.allocate(n);
 }
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline void
 allocator_deallocate(A& a, typename allocator_pointer<A>::type p,
     typename allocator_size_type<A>::type n)
@@ -416,7 +423,7 @@ class alloc_has_allocate {
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename std::enable_if<detail::alloc_has_allocate<A>::value,
     typename allocator_pointer<A>::type>::type
 allocator_allocate(A& a, typename allocator_size_type<A>::type n,
@@ -425,7 +432,7 @@ allocator_allocate(A& a, typename allocator_size_type<A>::type n,
     return a.allocate(n, h);
 }
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename std::enable_if<!detail::alloc_has_allocate<A>::value,
     typename allocator_pointer<A>::type>::type
 allocator_allocate(A& a, typename allocator_size_type<A>::type n,
@@ -521,7 +528,7 @@ allocator_construct(A&, T* p, V& v)
 }
 #endif
 #else
-template<class A, class T, class... Args>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class... Args>
 inline typename std::enable_if<detail::alloc_has_construct<A, T,
     Args...>::value>::type
 allocator_construct(A& a, T* p, Args&&... args)
@@ -529,7 +536,7 @@ allocator_construct(A& a, T* p, Args&&... args)
     a.construct(p, std::forward<Args>(args)...);
 }
 
-template<class A, class T, class... Args>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class... Args>
 inline typename std::enable_if<!detail::alloc_has_construct<A, T,
     Args...>::value>::type
 allocator_construct(A&, T* p, Args&&... args)
@@ -568,14 +575,14 @@ class alloc_has_destroy {
 
 } /* detail */
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline typename detail::alloc_if<detail::alloc_has_destroy<A, T>::value>::type
 allocator_destroy(A& a, T* p)
 {
     a.destroy(p);
 }
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline typename detail::alloc_if<!detail::alloc_has_destroy<A, T>::value>::type
 allocator_destroy(A&, T* p)
 {
@@ -628,7 +635,7 @@ class alloc_has_max_size {
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename detail::alloc_if<detail::alloc_has_max_size<A>::value,
     typename allocator_size_type<A>::type>::type
 allocator_max_size(const A& a) BOOST_NOEXCEPT
@@ -636,7 +643,7 @@ allocator_max_size(const A& a) BOOST_NOEXCEPT
     return a.max_size();
 }
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename detail::alloc_if<!detail::alloc_has_max_size<A>::value,
     typename allocator_size_type<A>::type>::type
 allocator_max_size(const A&) BOOST_NOEXCEPT
@@ -686,21 +693,21 @@ class alloc_has_soccc {
 
 } /* detail */
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename detail::alloc_if<detail::alloc_has_soccc<A>::value, A>::type
 allocator_select_on_container_copy_construction(const A& a)
 {
     return a.select_on_container_copy_construction();
 }
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline typename detail::alloc_if<!detail::alloc_has_soccc<A>::value, A>::type
 allocator_select_on_container_copy_construction(const A& a)
 {
     return a;
 }
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 allocator_destroy_n(A& a, T* p, std::size_t n)
 {
@@ -736,7 +743,7 @@ class alloc_destroyer {
 
 } /* detail */
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 allocator_construct_n(A& a, T* p, std::size_t n)
 {
@@ -747,7 +754,7 @@ allocator_construct_n(A& a, T* p, std::size_t n)
     d.size() = 0;
 }
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 inline void
 allocator_construct_n(A& a, T* p, std::size_t n, const T* l, std::size_t m)
 {
@@ -758,7 +765,7 @@ allocator_construct_n(A& a, T* p, std::size_t n, const T* l, std::size_t m)
     d.size() = 0;
 }
 
-template<class A, class T, class I>
+BOOST_CORE_MODULE_EXPORT template<class A, class T, class I>
 inline void
 allocator_construct_n(A& a, T* p, std::size_t n, I b)
 {
@@ -770,46 +777,46 @@ allocator_construct_n(A& a, T* p, std::size_t n, I b)
 }
 
 #if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_value_type_t = typename allocator_value_type<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_pointer_t = typename allocator_pointer<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_const_pointer_t = typename allocator_const_pointer<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_void_pointer_t = typename allocator_void_pointer<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_const_void_pointer_t =
     typename allocator_const_void_pointer<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_difference_type_t =
     typename allocator_difference_type<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_size_type_t = typename allocator_size_type<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_propagate_on_container_copy_assignment_t =
     typename allocator_propagate_on_container_copy_assignment<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_propagate_on_container_move_assignment_t =
     typename allocator_propagate_on_container_move_assignment<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_propagate_on_container_swap_t =
     typename allocator_propagate_on_container_swap<A>::type;
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 using allocator_is_always_equal_t =
     typename allocator_is_always_equal<A>::type;
 
-template<class A, class T>
+BOOST_CORE_MODULE_EXPORT template<class A, class T>
 using allocator_rebind_t = typename allocator_rebind<A, T>::type;
 #endif
 
@@ -832,3 +839,5 @@ _LIBCPP_SUPPRESS_DEPRECATED_POP
 #endif
 
 #endif
+
+#endif
diff --git a/include/boost/core/allocator_traits.hpp b/include/boost/core/allocator_traits.hpp
index bf8749d8..f30e5ea3 100644
--- a/include/boost/core/allocator_traits.hpp
+++ b/include/boost/core/allocator_traits.hpp
@@ -8,11 +8,18 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_ALLOCATOR_TRAITS_HPP
 #define BOOST_CORE_ALLOCATOR_TRAITS_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/allocator_access.hpp>
 
 namespace boost {
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct allocator_traits {
     typedef A allocator_type;
 
@@ -110,3 +117,5 @@ struct allocator_traits {
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/bit.hpp b/include/boost/core/bit.hpp
index 755ad401..3652a3c7 100644
--- a/include/boost/core/bit.hpp
+++ b/include/boost/core/bit.hpp
@@ -7,6 +7,14 @@
 # pragma once
 #endif
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
 // boost/core/bit.hpp
 //
 // A portable version of the C++20 standard header <bit>
@@ -15,16 +23,17 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/detail/static_assert.hpp>
 #include <boost/config.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
-#include <cstring>
-#include <cstdlib>
+#include <boost/config/std/limits.hpp>
+#include <boost/config/std/cstring.hpp>
+#include <boost/config/std/cstdlib.hpp>
 
 #if defined(_MSC_VER)
 
-# include <intrin.h>
+# include <boost/core/detail/intrin.hpp>
 # pragma intrinsic(_BitScanForward)
 # pragma intrinsic(_BitScanReverse)
 
@@ -69,7 +78,7 @@ namespace core
 
 #if defined(BOOST_CORE_HAS_BUILTIN_BIT_CAST)
 
-template<class To, class From>
+BOOST_CORE_MODULE_EXPORT template<class To, class From>
 BOOST_CONSTEXPR To bit_cast( From const & from ) BOOST_NOEXCEPT
 {
     return __builtin_bit_cast( To, from );
@@ -77,7 +86,7 @@ BOOST_CONSTEXPR To bit_cast( From const & from ) BOOST_NOEXCEPT
 
 #else
 
-template<class To, class From>
+BOOST_CORE_MODULE_EXPORT template<class To, class From>
 To bit_cast( From const & from ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( sizeof(To) == sizeof(From) );
@@ -123,7 +132,7 @@ BOOST_CONSTEXPR inline int countl_impl( boost::ulong_long_type x ) BOOST_NOEXCEP
 
 } // namespace detail
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR int countl_zero( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -293,7 +302,7 @@ inline int countl_impl( boost::uint64_t x ) BOOST_NOEXCEPT
 
 } // namespace detail
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CXX14_CONSTEXPR int countl_zero( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -320,7 +329,7 @@ BOOST_CXX14_CONSTEXPR int countl_zero( T x ) BOOST_NOEXCEPT
 
 #endif // defined(__GNUC__) || defined(__clang__)
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR int countl_one( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -362,7 +371,7 @@ BOOST_CONSTEXPR inline int countr_impl( boost::ulong_long_type x ) BOOST_NOEXCEP
 
 } // namespace detail
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR int countr_zero( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -518,7 +527,7 @@ inline int countr_impl( boost::uint64_t x ) BOOST_NOEXCEPT
 
 } // namespace detail
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CXX14_CONSTEXPR int countr_zero( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -545,7 +554,7 @@ BOOST_CXX14_CONSTEXPR int countr_zero( T x ) BOOST_NOEXCEPT
 
 #endif // defined(__GNUC__) || defined(__clang__)
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR int countr_one( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -595,7 +604,7 @@ BOOST_CORE_POPCOUNT_CONSTEXPR inline int popcount_impl( boost::ulong_long_type x
 
 #undef BOOST_CORE_POPCOUNT_CONSTEXPR
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR int popcount( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -628,7 +637,7 @@ BOOST_CXX14_CONSTEXPR inline int popcount_impl( boost::uint64_t x ) BOOST_NOEXCE
 
 } // namespace detail
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CXX14_CONSTEXPR int popcount( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -649,7 +658,7 @@ BOOST_CXX14_CONSTEXPR int popcount( T x ) BOOST_NOEXCEPT
 
 // rotating
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CXX14_CONSTEXPR T rotl( T x, int s ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -658,7 +667,7 @@ BOOST_CXX14_CONSTEXPR T rotl( T x, int s ) BOOST_NOEXCEPT
     return static_cast<T>( x << (static_cast<unsigned>( s ) & mask) | x >> (static_cast<unsigned>( -s ) & mask) );
 }
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CXX14_CONSTEXPR T rotr( T x, int s ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -669,7 +678,7 @@ BOOST_CXX14_CONSTEXPR T rotr( T x, int s ) BOOST_NOEXCEPT
 
 // integral powers of 2
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR bool has_single_bit( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -680,7 +689,7 @@ BOOST_CONSTEXPR bool has_single_bit( T x ) BOOST_NOEXCEPT
 // bit_width returns `int` now, https://cplusplus.github.io/LWG/issue3656
 // has been applied to C++20 as a DR
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR int bit_width( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -688,7 +697,7 @@ BOOST_CONSTEXPR int bit_width( T x ) BOOST_NOEXCEPT
     return std::numeric_limits<T>::digits - boost::core::countl_zero( x );
 }
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR T bit_floor( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -742,7 +751,7 @@ BOOST_CXX14_CONSTEXPR inline boost::uint64_t bit_ceil_impl( boost::uint64_t x )
 
 } // namespace detail
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CXX14_CONSTEXPR T bit_ceil( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
@@ -793,14 +802,14 @@ BOOST_CXX14_CONSTEXPR T bit_ceil( T x ) BOOST_NOEXCEPT
 
 #if !defined(BOOST_NO_CXX11_SCOPED_ENUMS)
 
-enum class endian
+BOOST_CORE_MODULE_EXPORT enum class endian
 {
     big,
     little,
     native BOOST_CORE_BIT_NATIVE_INITIALIZER
 };
 
-typedef endian endian_type;
+BOOST_CORE_MODULE_EXPORT typedef endian endian_type;
 
 #else
 
@@ -920,7 +929,7 @@ BOOST_CXX14_CONSTEXPR inline boost::uint64_t byteswap_impl( boost::uint64_t x )
 
 } // namespace detail
 
-template<class T> BOOST_CXX14_CONSTEXPR T byteswap( T x ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> BOOST_CXX14_CONSTEXPR T byteswap( T x ) BOOST_NOEXCEPT
 {
     BOOST_CORE_STATIC_ASSERT( std::numeric_limits<T>::is_integer );
 
@@ -951,4 +960,6 @@ template<class T> BOOST_CXX14_CONSTEXPR T byteswap( T x ) BOOST_NOEXCEPT
 # pragma warning(pop)
 #endif
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_BIT_HPP_INCLUDED
diff --git a/include/boost/core/checked_delete.hpp b/include/boost/core/checked_delete.hpp
index 67f3c742..df6ebbb7 100644
--- a/include/boost/core/checked_delete.hpp
+++ b/include/boost/core/checked_delete.hpp
@@ -7,6 +7,15 @@
 # pragma once
 #endif
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 //
@@ -28,7 +37,7 @@ namespace boost
 
 // verify that types are complete for increased safety
 
-template<class T> inline void checked_delete(T * x) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> inline void checked_delete(T * x) BOOST_NOEXCEPT
 {
 #if defined(__cpp_static_assert) && __cpp_static_assert >= 200410L
 
@@ -44,7 +53,7 @@ template<class T> inline void checked_delete(T * x) BOOST_NOEXCEPT
     delete x;
 }
 
-template<class T> inline void checked_array_delete(T * x) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> inline void checked_array_delete(T * x) BOOST_NOEXCEPT
 {
 #if defined(__cpp_static_assert) && __cpp_static_assert >= 200410L
 
@@ -64,7 +73,7 @@ template<class T> inline void checked_array_delete(T * x) BOOST_NOEXCEPT
 namespace checked_deleters
 {
 
-template<class T> struct checked_deleter
+BOOST_CORE_MODULE_EXPORT template<class T> struct checked_deleter
 {
     typedef void result_type;
     typedef T * argument_type;
@@ -76,7 +85,7 @@ template<class T> struct checked_deleter
     }
 };
 
-template<class T> struct checked_array_deleter
+BOOST_CORE_MODULE_EXPORT template<class T> struct checked_array_deleter
 {
     typedef void result_type;
     typedef T * argument_type;
@@ -89,9 +98,11 @@ template<class T> struct checked_array_deleter
 
 } // namespace checked_deleters
 
-using checked_deleters::checked_deleter;
-using checked_deleters::checked_array_deleter;
+BOOST_CORE_MODULE_EXPORT using checked_deleters::checked_deleter;
+BOOST_CORE_MODULE_EXPORT using checked_deleters::checked_array_deleter;
 
 } // namespace boost
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_CHECKED_DELETE_HPP
diff --git a/include/boost/core/cmath.hpp b/include/boost/core/cmath.hpp
index 9cfe26e1..4717d6dc 100644
--- a/include/boost/core/cmath.hpp
+++ b/include/boost/core/cmath.hpp
@@ -16,14 +16,21 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
-#include <cmath>
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/config/std/cmath.hpp>
 
 #if defined(BOOST_CORE_USE_GENERIC_CMATH) || (!defined(_MSC_VER) && !defined(FP_SUBNORMAL))
 
 #include <boost/core/detail/static_assert.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
-#include <cstring>
+#include <boost/config/std/limits.hpp>
+#include <boost/config/std/cstring.hpp>
 
 namespace boost
 {
@@ -32,35 +39,35 @@ namespace core
 
 // fpclassify return values
 
-int const fp_zero = 0;
-int const fp_subnormal = 1;
-int const fp_normal = 2;
-int const fp_infinite = 3;
-int const fp_nan = 4;
+BOOST_CORE_MODULE_EXPORT int const fp_zero = 0;
+BOOST_CORE_MODULE_EXPORT int const fp_subnormal = 1;
+BOOST_CORE_MODULE_EXPORT int const fp_normal = 2;
+BOOST_CORE_MODULE_EXPORT int const fp_infinite = 3;
+BOOST_CORE_MODULE_EXPORT int const fp_nan = 4;
 
 // Classification functions
 
-template<class T> bool isfinite( T x )
+BOOST_CORE_MODULE_EXPORT template<class T> bool isfinite( T x )
 {
     return x <= (std::numeric_limits<T>::max)() && x >= -(std::numeric_limits<T>::max)();
 }
 
-template<class T> bool isinf( T x )
+BOOST_CORE_MODULE_EXPORT template<class T> bool isinf( T x )
 {
     return x > (std::numeric_limits<T>::max)() || x < -(std::numeric_limits<T>::max)();
 }
 
-template<class T> bool isnan( T x )
+BOOST_CORE_MODULE_EXPORT template<class T> bool isnan( T x )
 {
     return !isfinite( x ) && !isinf( x );
 }
 
-template<class T> bool isnormal( T x )
+BOOST_CORE_MODULE_EXPORT template<class T> bool isnormal( T x )
 {
     return isfinite( x ) && ( x >= (std::numeric_limits<T>::min)() || x <= -(std::numeric_limits<T>::min)() );
 }
 
-template<class T> int fpclassify( T x )
+BOOST_CORE_MODULE_EXPORT template<class T> int fpclassify( T x )
 {
     if( x == 0 ) return fp_zero;
 
@@ -77,7 +84,7 @@ template<class T> int fpclassify( T x )
 
 // Sign manipulation functions
 
-inline bool signbit( float x )
+BOOST_CORE_MODULE_EXPORT inline bool signbit( float x )
 {
     boost::int32_t y;
 
@@ -88,7 +95,7 @@ inline bool signbit( float x )
     return y < 0;
 }
 
-inline bool signbit( double x )
+BOOST_CORE_MODULE_EXPORT inline bool signbit( double x )
 {
     boost::int64_t y;
 
@@ -99,12 +106,12 @@ inline bool signbit( double x )
     return y < 0;
 }
 
-inline bool signbit( long double x )
+BOOST_CORE_MODULE_EXPORT inline bool signbit( long double x )
 {
     return signbit( static_cast<double>( x ) );
 }
 
-template<class T> T copysign( T x, T y )
+BOOST_CORE_MODULE_EXPORT template<class T> T copysign( T x, T y )
 {
     return signbit( x ) == signbit( y )? x: -x;
 }
@@ -115,6 +122,11 @@ template<class T> T copysign( T x, T y )
 #else // defined(BOOST_CORE_USE_GENERIC_CMATH)
 
 #if defined(_MSC_VER) && _MSC_VER < 1800
+// This MSVC version shouldn't support modules.
+// Guard the include, just in case.
+# ifdef BOOST_USE_MODULES
+#   error "Your compiler is not supported with BOOST_USE_MODULES"
+# endif
 # include <float.h>
 #endif
 
@@ -235,25 +247,25 @@ inline int fpclassify( long double x )
 
 #else
 
-using std::isfinite;
-using std::isnan;
-using std::isinf;
-using std::isnormal;
-using std::fpclassify;
+BOOST_CORE_MODULE_EXPORT using std::isfinite;
+BOOST_CORE_MODULE_EXPORT using std::isnan;
+BOOST_CORE_MODULE_EXPORT using std::isinf;
+BOOST_CORE_MODULE_EXPORT using std::isnormal;
+BOOST_CORE_MODULE_EXPORT using std::fpclassify;
 
-int const fp_zero = FP_ZERO;
-int const fp_subnormal = FP_SUBNORMAL;
-int const fp_normal = FP_NORMAL;
-int const fp_infinite = FP_INFINITE;
-int const fp_nan = FP_NAN;
+BOOST_CORE_MODULE_EXPORT int const fp_zero = FP_ZERO;
+BOOST_CORE_MODULE_EXPORT int const fp_subnormal = FP_SUBNORMAL;
+BOOST_CORE_MODULE_EXPORT int const fp_normal = FP_NORMAL;
+BOOST_CORE_MODULE_EXPORT int const fp_infinite = FP_INFINITE;
+BOOST_CORE_MODULE_EXPORT int const fp_nan = FP_NAN;
 
-using std::signbit;
+BOOST_CORE_MODULE_EXPORT using std::signbit;
 
 // std::copysign doesn't exist in libstdc++ under -std=c++03
 
 #if !defined(__GNUC__)
 
-template<class T> T copysign( T x, T y )
+BOOST_CORE_MODULE_EXPORT template<class T> T copysign( T x, T y )
 {
     return std::copysign( x, y );
 }
@@ -282,7 +294,7 @@ inline long double copysign_impl( long double x, long double y )
 
 } // namespace detail
 
-template<class T> T copysign( T x, T y )
+BOOST_CORE_MODULE_EXPORT template<class T> T copysign( T x, T y )
 {
     return boost::core::detail::copysign_impl( x, y );
 }
@@ -295,4 +307,6 @@ template<class T> T copysign( T x, T y )
 
 #endif // defined(BOOST_CORE_USE_GENERIC_CMATH)
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_CMATH_HPP_INCLUDED
diff --git a/include/boost/core/data.hpp b/include/boost/core/data.hpp
index 03ac5228..52c1c022 100644
--- a/include/boost/core/data.hpp
+++ b/include/boost/core/data.hpp
@@ -8,46 +8,55 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_DATA_HPP
 #define BOOST_CORE_DATA_HPP
 
-#include <iterator>
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/config/std/iterator.hpp>
 
 // Note: MSVC doesn't define __cpp_lib_nonmember_container_access but supports the feature even in C++14 mode
 #if (defined(__cpp_lib_nonmember_container_access) && (__cpp_lib_nonmember_container_access >= 201411l)) || \
     (defined(_MSC_VER) && (_MSC_VER >= 1900))
 
 namespace boost {
-using std::data;
+BOOST_CORE_MODULE_EXPORT using std::data;
 } /* boost */
 
 #else // (defined(__cpp_lib_nonmember_container_access) ...
 
-#include <cstddef>
-#include <initializer_list>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/config/std/initializer_list.hpp>
 
 namespace boost {
 
 template<class C>
-inline constexpr auto
+BOOST_CORE_MODULE_EXPORT inline constexpr auto
 data(C& c) noexcept(noexcept(c.data())) -> decltype(c.data())
 {
     return c.data();
 }
 
 template<class C>
-inline constexpr auto
+BOOST_CORE_MODULE_EXPORT inline constexpr auto
 data(const C& c) noexcept(noexcept(c.data())) -> decltype(c.data())
 {
     return c.data();
 }
 
 template<class T, std::size_t N>
-inline constexpr T*
+BOOST_CORE_MODULE_EXPORT inline constexpr T*
 data(T(&a)[N]) noexcept
 {
     return a;
 }
 
 template<class T>
-inline constexpr const T*
+BOOST_CORE_MODULE_EXPORT inline constexpr const T*
 data(std::initializer_list<T> l) noexcept
 {
     return l.begin();
@@ -58,3 +67,5 @@ data(std::initializer_list<T> l) noexcept
 #endif // (defined(__cpp_lib_nonmember_container_access) ...
 
 #endif
+
+#endif
diff --git a/include/boost/core/default_allocator.hpp b/include/boost/core/default_allocator.hpp
index 6640473f..cd389524 100644
--- a/include/boost/core/default_allocator.hpp
+++ b/include/boost/core/default_allocator.hpp
@@ -8,13 +8,23 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_DEFAULT_ALLOCATOR_HPP
 #define BOOST_CORE_DEFAULT_ALLOCATOR_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
-#include <new>
-#include <cstddef>
+#include <boost/config/std/new.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost {
 
-#if defined(BOOST_NO_EXCEPTIONS)
+// Avoid throw_exception from being attached to Boost.Core in module builds
+#if defined(BOOST_NO_EXCEPTIONS) && !defined(BOOST_USE_MODULES)
 BOOST_NORETURN void throw_exception(const std::exception&);
 #endif
 
@@ -54,7 +64,7 @@ struct add_reference<const void> {
     typedef const void type;
 };
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 struct default_allocator {
     typedef T value_type;
     typedef T* pointer;
@@ -134,7 +144,7 @@ struct default_allocator {
 #endif
 };
 
-template<class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class T, class U>
 BOOST_CONSTEXPR inline bool
 operator==(const default_allocator<T>&,
     const default_allocator<U>&) BOOST_NOEXCEPT
@@ -142,7 +152,7 @@ operator==(const default_allocator<T>&,
     return true;
 }
 
-template<class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class T, class U>
 BOOST_CONSTEXPR inline bool
 operator!=(const default_allocator<T>&,
     const default_allocator<U>&) BOOST_NOEXCEPT
@@ -152,8 +162,10 @@ operator!=(const default_allocator<T>&,
 
 } /* default_ */
 
-using default_::default_allocator;
+BOOST_CORE_MODULE_EXPORT using default_::default_allocator;
 
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/demangle.hpp b/include/boost/core/demangle.hpp
index 63e5f7c3..cdefbfa5 100644
--- a/include/boost/core/demangle.hpp
+++ b/include/boost/core/demangle.hpp
@@ -10,35 +10,26 @@
 // See accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
 #include <boost/config.hpp>
-#include <string>
+#include <boost/config/std/string.hpp>
+#include <boost/core/detail/modules.hpp>
 
 #if defined(BOOST_HAS_PRAGMA_ONCE)
 # pragma once
 #endif
 
-// __has_include is currently supported by GCC and Clang. However GCC 4.9 may have issues and
-// returns 1 for 'defined( __has_include )', while '__has_include' is actually not supported:
-// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63662
-#if defined( __has_include ) && (!defined( BOOST_GCC ) || (__GNUC__ + 0) >= 5)
-# if __has_include(<cxxabi.h>)
-#  define BOOST_CORE_HAS_CXXABI_H
-# endif
-#elif defined( __GLIBCXX__ ) || defined( __GLIBCPP__ )
-# define BOOST_CORE_HAS_CXXABI_H
-#endif
-
+#include <boost/core/detail/demangle_cxxabi.hpp>
 #if defined( BOOST_CORE_HAS_CXXABI_H )
-# include <cxxabi.h>
-// For some architectures (mips, mips64, x86, x86_64) cxxabi.h in Android NDK is implemented by gabi++ library
-// (https://android.googlesource.com/platform/ndk/+/master/sources/cxx-stl/gabi++/), which does not implement
-// abi::__cxa_demangle(). We detect this implementation by checking the include guard here.
-# if defined( __GABIXX_CXXABI_H__ )
-#  undef BOOST_CORE_HAS_CXXABI_H
-# else
-#  include <cstdlib>
-#  include <cstddef>
-# endif
+#  include <boost/config/std/cstdlib.hpp>
+#  include <boost/config/std/cstddef.hpp>
 #endif
 
 namespace boost
@@ -47,26 +38,26 @@ namespace boost
 namespace core
 {
 
-inline char const * demangle_alloc( char const * name ) BOOST_NOEXCEPT;
-inline void demangle_free( char const * name ) BOOST_NOEXCEPT;
+BOOST_CORE_MODULE_EXPORT inline char const * demangle_alloc( char const * name ) BOOST_NOEXCEPT;
+BOOST_CORE_MODULE_EXPORT inline void demangle_free( char const * name ) BOOST_NOEXCEPT;
 
-class scoped_demangled_name
+BOOST_CORE_MODULE_EXPORT class scoped_demangled_name
 {
 private:
     char const * m_p;
 
 public:
-    explicit scoped_demangled_name( char const * name ) BOOST_NOEXCEPT :
+    inline explicit scoped_demangled_name( char const * name ) BOOST_NOEXCEPT :
         m_p( demangle_alloc( name ) )
     {
     }
 
-    ~scoped_demangled_name() BOOST_NOEXCEPT
+    inline ~scoped_demangled_name() BOOST_NOEXCEPT
     {
         demangle_free( m_p );
     }
 
-    char const * get() const BOOST_NOEXCEPT
+    inline char const * get() const BOOST_NOEXCEPT
     {
         return m_p;
     }
@@ -78,19 +69,19 @@ class scoped_demangled_name
 
 #if defined( BOOST_CORE_HAS_CXXABI_H )
 
-inline char const * demangle_alloc( char const * name ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT inline char const * demangle_alloc( char const * name ) BOOST_NOEXCEPT
 {
     int status = 0;
     std::size_t size = 0;
     return abi::__cxa_demangle( name, NULL, &size, &status );
 }
 
-inline void demangle_free( char const * name ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT inline void demangle_free( char const * name ) BOOST_NOEXCEPT
 {
     std::free( const_cast< char* >( name ) );
 }
 
-inline std::string demangle( char const * name )
+BOOST_CORE_MODULE_EXPORT inline std::string demangle( char const * name )
 {
     scoped_demangled_name demangled_name( name );
     char const * p = demangled_name.get();
@@ -101,16 +92,16 @@ inline std::string demangle( char const * name )
 
 #else
 
-inline char const * demangle_alloc( char const * name ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT inline char const * demangle_alloc( char const * name ) BOOST_NOEXCEPT
 {
     return name;
 }
 
-inline void demangle_free( char const * ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT inline void demangle_free( char const * ) BOOST_NOEXCEPT
 {
 }
 
-inline std::string demangle( char const * name )
+BOOST_CORE_MODULE_EXPORT inline std::string demangle( char const * name )
 {
     return name;
 }
@@ -123,4 +114,6 @@ inline std::string demangle( char const * name )
 
 #undef BOOST_CORE_HAS_CXXABI_H
 
+#endif
+
 #endif // #ifndef BOOST_CORE_DEMANGLE_HPP_INCLUDED
diff --git a/include/boost/core/detail/demangle_cxxabi.hpp b/include/boost/core/detail/demangle_cxxabi.hpp
new file mode 100644
index 00000000..403ec159
--- /dev/null
+++ b/include/boost/core/detail/demangle_cxxabi.hpp
@@ -0,0 +1,40 @@
+// Make the header safe to include from the purview
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_DETAIL_CXXABI_HPP_INCLUDED)
+#  error "Please #include <boost/core/detail/demangle_cxxabi.hpp> in your module global fragment"
+#endif
+
+#ifndef BOOST_CORE_DETAIL_CXXABI_HPP_INCLUDED
+#define BOOST_CORE_DETAIL_CXXABI_HPP_INCLUDED
+
+// Extracted from core::demangle
+//
+// Copyright 2014 Peter Dimov
+// Copyright 2014 Andrey Semashev
+//
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt
+
+// __has_include is currently supported by GCC and Clang. However GCC 4.9 may have issues and
+// returns 1 for 'defined( __has_include )', while '__has_include' is actually not supported:
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63662
+#if defined( __has_include ) && (!defined( BOOST_GCC ) || (__GNUC__ + 0) >= 5)
+# if __has_include(<cxxabi.h>)
+#  define BOOST_CORE_HAS_CXXABI_H
+# endif
+#elif defined( __GLIBCXX__ ) || defined( __GLIBCPP__ )
+# define BOOST_CORE_HAS_CXXABI_H
+#endif
+
+#if defined( BOOST_CORE_HAS_CXXABI_H )
+# include <cxxabi.h>
+// For some archtectures (mips, mips64, x86, x86_64) cxxabi.h in Android NDK is implemented by gabi++ library
+// (https://android.googlesource.com/platform/ndk/+/master/sources/cxx-stl/gabi++/), which does not implement
+// abi::__cxa_demangle(). We detect this implementation by checking the include guard here.
+# if defined( __GABIXX_CXXABI_H__ )
+#  undef BOOST_CORE_HAS_CXXABI_H
+# endif
+#endif
+
+
+#endif
diff --git a/include/boost/core/detail/intrin.hpp b/include/boost/core/detail/intrin.hpp
new file mode 100644
index 00000000..1b5e83f7
--- /dev/null
+++ b/include/boost/core/detail/intrin.hpp
@@ -0,0 +1,10 @@
+// Module-aware wrapper for <intrin.h>
+// Ensures that we don't accidentally pour names into Boost.Core's module purview
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_INTRIN_INCLUDED)
+#  error "Please #include <boost/core/detail/intrin.hpp> in your module global fragment"
+#endif
+
+#ifndef BOOST_CORE_INTRIN_INCLUDED
+#define BOOST_CORE_INTRIN_INCLUDED
+#include <intrin.h>
+#endif
diff --git a/include/boost/core/detail/is_same.hpp b/include/boost/core/detail/is_same.hpp
index 634d3004..cca43750 100644
--- a/include/boost/core/detail/is_same.hpp
+++ b/include/boost/core/detail/is_same.hpp
@@ -9,6 +9,15 @@
 // See accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 #if defined(BOOST_HAS_PRAGMA_ONCE)
@@ -22,7 +31,7 @@ namespace core
 namespace detail
 {
 
-template< class T1, class T2 > struct is_same
+BOOST_CORE_MODULE_EXPORT template< class T1, class T2 > struct is_same
 {
     BOOST_STATIC_CONSTANT( bool, value = false );
 };
@@ -36,4 +45,6 @@ template< class T > struct is_same< T, T >
 } // namespace core
 } // namespace boost
 
+#endif
+
 #endif // #ifndef BOOST_CORE_DETAIL_IS_SAME_HPP_INCLUDED
diff --git a/include/boost/core/detail/lwt_unattended.hpp b/include/boost/core/detail/lwt_unattended.hpp
index 96fc5fc5..0d3769f9 100644
--- a/include/boost/core/detail/lwt_unattended.hpp
+++ b/include/boost/core/detail/lwt_unattended.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_DETAIL_LWT_UNATTENDED_HPP_INCLUDED)
+#  error "Please #include <boost/core/detail/lwt_unattend.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_DETAIL_LWT_UNATTENDED_HPP_INCLUDED
 #define BOOST_CORE_DETAIL_LWT_UNATTENDED_HPP_INCLUDED
 
diff --git a/include/boost/core/detail/minstd_rand.hpp b/include/boost/core/detail/minstd_rand.hpp
index bedafb28..0ebccd12 100644
--- a/include/boost/core/detail/minstd_rand.hpp
+++ b/include/boost/core/detail/minstd_rand.hpp
@@ -28,11 +28,11 @@ class minstd_rand
 
 public:
 
-    minstd_rand(): x_( 1 )
+    inline minstd_rand(): x_( 1 )
     {
     }
 
-    explicit minstd_rand( boost::uint_least32_t x ): x_( x % m )
+    inline explicit minstd_rand( boost::uint_least32_t x ): x_( x % m )
     {
         if( x_ == 0 )
         {
@@ -40,7 +40,7 @@ class minstd_rand
         }
     }
 
-    boost::uint_least32_t operator()()
+    inline boost::uint_least32_t operator()()
     {
         boost::uint_least64_t y = x_;
 
diff --git a/include/boost/core/detail/modules.hpp b/include/boost/core/detail/modules.hpp
new file mode 100644
index 00000000..65018a41
--- /dev/null
+++ b/include/boost/core/detail/modules.hpp
@@ -0,0 +1,20 @@
+//
+//  Copyright (c) 2025 Ruben Perez Hidalgo
+//
+//  Distributed under the Boost Software License, Version 1.0. (See
+//  accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_CORE_DETAIL_MODULES_HPP
+#define BOOST_CORE_DETAIL_MODULES_HPP
+
+// BOOST_CORE_MODULE_EXPORT
+
+#ifdef BOOST_USE_MODULES
+#  define BOOST_CORE_MODULE_EXPORT export
+#else
+#  define BOOST_CORE_MODULE_EXPORT
+#endif
+
+#endif
diff --git a/include/boost/core/detail/sp_thread_pause.hpp b/include/boost/core/detail/sp_thread_pause.hpp
index 8971fbd1..a4e327f6 100644
--- a/include/boost/core/detail/sp_thread_pause.hpp
+++ b/include/boost/core/detail/sp_thread_pause.hpp
@@ -31,12 +31,12 @@
 
 #elif defined(_MSC_VER) && ( defined(_M_IX86) || defined(_M_X64) )
 
-# include <intrin.h>
+# include <boost/core/detail/intrin.hpp>
 # define BOOST_CORE_SP_PAUSE() _mm_pause()
 
 #elif defined(_MSC_VER) && ( defined(_M_ARM) || defined(_M_ARM64) )
 
-# include <intrin.h>
+# include <boost/core/detail/intrin.hpp>
 # define BOOST_CORE_SP_PAUSE() __yield()
 
 #elif defined(__GNUC__) && ( defined(__i386__) || defined(__x86_64__) )
diff --git a/include/boost/core/detail/splitmix64.hpp b/include/boost/core/detail/splitmix64.hpp
index e91ab0a2..0bdf9ff5 100644
--- a/include/boost/core/detail/splitmix64.hpp
+++ b/include/boost/core/detail/splitmix64.hpp
@@ -9,6 +9,15 @@
 // derived from Sebastiano Vigna's public domain implementation
 // http://xorshift.di.unimi.it/splitmix64.c
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/cstdint.hpp>
 
 namespace boost
@@ -16,6 +25,7 @@ namespace boost
 namespace detail
 {
 
+BOOST_CORE_MODULE_EXPORT
 class splitmix64
 {
 private:
@@ -24,15 +34,15 @@ class splitmix64
 
 public:
 
-    splitmix64(): x_( 0 )
+    inline splitmix64(): x_( 0 )
     {
     }
 
-    explicit splitmix64( boost::uint64_t seed ): x_( seed )
+    inline explicit splitmix64( boost::uint64_t seed ): x_( seed )
     {
     }
 
-    boost::uint64_t operator()()
+    inline boost::uint64_t operator()()
     {
         x_ += ( boost::uint64_t(0x9e3779b9u) << 32 ) + 0x7f4a7c15u;
 
@@ -51,4 +61,6 @@ class splitmix64
 } // namespace detail
 } // namespace boost
 
+#endif
+
 #endif // #ifndef BOOST_CORE_DETAIL_SPLITMIX64_HPP_INCLUDED
diff --git a/include/boost/core/detail/static_assert.hpp b/include/boost/core/detail/static_assert.hpp
index f62f7671..ca71b7ba 100644
--- a/include/boost/core/detail/static_assert.hpp
+++ b/include/boost/core/detail/static_assert.hpp
@@ -12,7 +12,7 @@
 #else
 
 #include <boost/config.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost
 {
diff --git a/include/boost/core/detail/string_view.hpp b/include/boost/core/detail/string_view.hpp
index b0c256f5..a14494b4 100644
--- a/include/boost/core/detail/string_view.hpp
+++ b/include/boost/core/detail/string_view.hpp
@@ -7,6 +7,14 @@
 # pragma once
 #endif
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
 // boost::core::basic_string_view<Ch>
 //
 // Copyright 2021 Peter Dimov
@@ -15,27 +23,28 @@
 
 #include <boost/core/enable_if.hpp>
 #include <boost/core/detail/is_same.hpp>
+#include <boost/core/detail/modules.hpp>
 #include <boost/assert.hpp>
 #include <boost/assert/source_location.hpp>
 #include <boost/throw_exception.hpp>
 #include <boost/config.hpp>
-#include <string>
-#include <algorithm>
-#include <utility>
-#include <stdexcept>
-#include <cstddef>
-#include <cstring>
-#include <climits>
-#include <iosfwd>
-#include <ios>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/utility.hpp>
+#include <boost/config/std/stdexcept.hpp>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/config/std/cstring.hpp>
+#include <boost/config/std/climits.hpp>
+#include <boost/config/std/iosfwd.hpp>
+#include <boost/config/std/ios.hpp>
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 #if !defined(BOOST_NO_CXX20_HDR_CONCEPTS) // std::common_reference_with
-# include <type_traits>
+# include <boost/config/std/type_traits.hpp>
 #endif
 #if !defined(BOOST_NO_CXX20_HDR_FORMAT)
-# include <format> // std::formatter
+# include <boost/config/std/format.hpp> // std::formatter
 #endif
 
 namespace boost
@@ -336,6 +345,7 @@ template<class Ch> BOOST_CXX14_CONSTEXPR std::size_t find_last_not_of( Ch const*
 
 } // namespace detail
 
+BOOST_CORE_MODULE_EXPORT
 template<class Ch> class basic_string_view
 {
 private:
@@ -1185,6 +1195,7 @@ template<class Ch> class basic_string_view
 
 // stream inserter
 
+BOOST_CORE_MODULE_EXPORT
 template<class Ch> std::basic_ostream<Ch>& operator<<( std::basic_ostream<Ch>& os, basic_string_view<Ch> str )
 {
     Ch const* p = str.data();
@@ -1221,19 +1232,19 @@ template<class Ch> BOOST_CONSTEXPR_OR_CONST std::size_t basic_string_view<Ch>::n
 
 // typedef names
 
-typedef basic_string_view<char> string_view;
-typedef basic_string_view<wchar_t> wstring_view;
+BOOST_CORE_MODULE_EXPORT typedef basic_string_view<char> string_view;
+BOOST_CORE_MODULE_EXPORT typedef basic_string_view<wchar_t> wstring_view;
 
 #if !defined(BOOST_NO_CXX11_CHAR16_T)
-typedef basic_string_view<char16_t> u16string_view;
+BOOST_CORE_MODULE_EXPORT typedef basic_string_view<char16_t> u16string_view;
 #endif
 
 #if !defined(BOOST_NO_CXX11_CHAR32_T)
-typedef basic_string_view<char32_t> u32string_view;
+BOOST_CORE_MODULE_EXPORT typedef basic_string_view<char32_t> u32string_view;
 #endif
 
 #if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
-typedef basic_string_view<char8_t> u8string_view;
+BOOST_CORE_MODULE_EXPORT typedef basic_string_view<char8_t> u8string_view;
 #endif
 
 } // namespace core
@@ -1275,4 +1286,6 @@ struct std::formatter<boost::core::basic_string_view<Ch>, Ch2>: std::formatter<s
 
 #endif
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_STRING_VIEW_HPP_INCLUDED
diff --git a/include/boost/core/empty_value.hpp b/include/boost/core/empty_value.hpp
index 5eeee51f..99b861ed 100644
--- a/include/boost/core/empty_value.hpp
+++ b/include/boost/core/empty_value.hpp
@@ -8,9 +8,16 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_EMPTY_VALUE_HPP
 #define BOOST_CORE_EMPTY_VALUE_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-#include <utility>
+#include <boost/config/std/utility.hpp>
 #endif
 
 #if defined(BOOST_GCC_VERSION) && (BOOST_GCC_VERSION >= 40700)
@@ -43,11 +50,11 @@ struct use_empty_value_base {
     };
 };
 
-struct empty_init_t { };
+BOOST_CORE_MODULE_EXPORT struct empty_init_t { };
 
 namespace empty_ {
 
-template<class T, unsigned N = 0,
+BOOST_CORE_MODULE_EXPORT template<class T, unsigned N = 0,
     bool E = boost::use_empty_value_base<T>::value>
 class empty_value {
 public:
@@ -190,9 +197,9 @@ class empty_value<T, N, true>
 
 } /* empty_ */
 
-using empty_::empty_value;
+BOOST_CORE_MODULE_EXPORT using empty_::empty_value;
 
-BOOST_INLINE_CONSTEXPR empty_init_t empty_init = empty_init_t();
+BOOST_CORE_MODULE_EXPORT BOOST_INLINE_CONSTEXPR empty_init_t empty_init = empty_init_t();
 
 } /* boost */
 
@@ -201,3 +208,5 @@ BOOST_INLINE_CONSTEXPR empty_init_t empty_init = empty_init_t();
 #endif
 
 #endif
+
+#endif
diff --git a/include/boost/core/enable_if.hpp b/include/boost/core/enable_if.hpp
index 5dcef1e0..c09f3d71 100644
--- a/include/boost/core/enable_if.hpp
+++ b/include/boost/core/enable_if.hpp
@@ -14,14 +14,23 @@
 #ifndef BOOST_CORE_ENABLE_IF_HPP
 #define BOOST_CORE_ENABLE_IF_HPP
 
-#include "boost/config.hpp"
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/config.hpp>
 
 // Even the definition of enable_if causes problems on some compilers,
 // so it's macroed out for all compilers that do not support SFINAE
 
 #ifndef BOOST_NO_SFINAE
 
-namespace boost
+BOOST_CORE_MODULE_EXPORT namespace boost
 {
   template<typename T, typename R=void>
   struct enable_if_has_type
@@ -126,3 +135,5 @@ namespace boost {
 #endif // BOOST_NO_SFINAE
 
 #endif
+
+#endif
diff --git a/include/boost/core/exchange.hpp b/include/boost/core/exchange.hpp
index bc8a9fcd..8302e91c 100644
--- a/include/boost/core/exchange.hpp
+++ b/include/boost/core/exchange.hpp
@@ -8,16 +8,25 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_EXCHANGE_HPP
 #define BOOST_CORE_EXCHANGE_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 #include <boost/config/workaround.hpp>
-#include <utility>
+#include <boost/config/std/utility.hpp>
 #endif
 
 namespace boost {
 
 #if defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-template<class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class T, class U>
 inline T exchange(T& t, const U& u)
 {
     T v = t;
@@ -26,7 +35,7 @@ inline T exchange(T& t, const U& u)
 }
 #else
 #if BOOST_WORKAROUND(BOOST_MSVC, < 1800)
-template<class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class T, class U>
 inline T exchange(T& t, U&& u)
 {
     T v = std::move(t);
@@ -34,7 +43,7 @@ inline T exchange(T& t, U&& u)
     return v;
 }
 #else
-template<class T, class U = T>
+BOOST_CORE_MODULE_EXPORT template<class T, class U = T>
 BOOST_CXX14_CONSTEXPR inline T exchange(T& t, U&& u)
 {
     T v = std::move(t);
@@ -47,3 +56,5 @@ BOOST_CXX14_CONSTEXPR inline T exchange(T& t, U&& u)
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/explicit_operator_bool.hpp b/include/boost/core/explicit_operator_bool.hpp
index d689f114..2e244950 100644
--- a/include/boost/core/explicit_operator_bool.hpp
+++ b/include/boost/core/explicit_operator_bool.hpp
@@ -15,6 +15,11 @@
  * C++11.
  */
 
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_EXPLICIT_OPERATOR_BOOL_HPP)
+#  error "Please #include <boost/core/explicit_operator_bool.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_EXPLICIT_OPERATOR_BOOL_HPP
 #define BOOST_CORE_EXPLICIT_OPERATOR_BOOL_HPP
 
diff --git a/include/boost/core/fclose_deleter.hpp b/include/boost/core/fclose_deleter.hpp
index 7a31cb15..ec597b6a 100644
--- a/include/boost/core/fclose_deleter.hpp
+++ b/include/boost/core/fclose_deleter.hpp
@@ -17,7 +17,14 @@
 #ifndef BOOST_CORE_FCLOSE_DELETER_HPP
 #define BOOST_CORE_FCLOSE_DELETER_HPP
 
-#include <cstdio>
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/config/std/cstdio.hpp>
 #include <boost/config.hpp>
 
 #ifdef BOOST_HAS_PRAGMA_ONCE
@@ -30,14 +37,14 @@ namespace boost {
 namespace fclose_deleter_ns {
 
 //! A function object that closes a file
-struct fclose_deleter
+BOOST_CORE_MODULE_EXPORT struct fclose_deleter
 {
     //! Function object result type
     typedef void result_type;
     /*!
      * Closes the file handle
      */
-    void operator() (std::FILE* p) const BOOST_NOEXCEPT
+    inline void operator() (std::FILE* p) const BOOST_NOEXCEPT
     {
         if (BOOST_LIKELY(!!p))
             std::fclose(p);
@@ -46,8 +53,10 @@ struct fclose_deleter
 
 } // namespace fclose_deleter_ns
 
-using fclose_deleter_ns::fclose_deleter;
+BOOST_CORE_MODULE_EXPORT using fclose_deleter_ns::fclose_deleter;
 
 } // namespace boost
 
+#endif
+
 #endif // BOOST_CORE_FCLOSE_DELETER_HPP
diff --git a/include/boost/core/first_scalar.hpp b/include/boost/core/first_scalar.hpp
index 5373542e..2fd31900 100644
--- a/include/boost/core/first_scalar.hpp
+++ b/include/boost/core/first_scalar.hpp
@@ -8,8 +8,15 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_FIRST_SCALAR_HPP
 #define BOOST_CORE_FIRST_SCALAR_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost {
 namespace detail {
@@ -26,14 +33,14 @@ struct make_scalar<T[N]> {
 
 } /* detail */
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR inline T*
 first_scalar(T* p) BOOST_NOEXCEPT
 {
     return p;
 }
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 BOOST_CONSTEXPR inline typename detail::make_scalar<T>::type*
 first_scalar(T (*p)[N]) BOOST_NOEXCEPT
 {
@@ -43,3 +50,5 @@ first_scalar(T (*p)[N]) BOOST_NOEXCEPT
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/functor.hpp b/include/boost/core/functor.hpp
index f3ee11b9..8ad82fd9 100644
--- a/include/boost/core/functor.hpp
+++ b/include/boost/core/functor.hpp
@@ -16,13 +16,21 @@
 #ifndef BOOST_CORE_FUNCTOR_HPP
 #define BOOST_CORE_FUNCTOR_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+
 namespace boost::core {
 
 // Block unintended ADL
 namespace functor_ns {
 
 //! A function object that invokes a function specified as its template parameter
-template< auto Function >
+BOOST_CORE_MODULE_EXPORT template< auto Function >
 struct functor
 {
     template< typename... Args >
@@ -34,8 +42,10 @@ struct functor
 
 } // namespace functor_ns
 
-using functor_ns::functor;
+BOOST_CORE_MODULE_EXPORT using functor_ns::functor;
 
 } // namespace boost::core
 
+#endif
+
 #endif // BOOST_CORE_FUNCTOR_HPP
diff --git a/include/boost/core/identity.hpp b/include/boost/core/identity.hpp
index f27733be..53339618 100644
--- a/include/boost/core/identity.hpp
+++ b/include/boost/core/identity.hpp
@@ -8,14 +8,21 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_IDENTITY_HPP
 #define BOOST_CORE_IDENTITY_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-#include <utility>
+#include <boost/config/std/utility.hpp>
 #endif
 
 namespace boost {
 
-struct identity {
+BOOST_CORE_MODULE_EXPORT struct identity {
     typedef void is_transparent;
 
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
@@ -59,3 +66,5 @@ struct identity {
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/ignore_unused.hpp b/include/boost/core/ignore_unused.hpp
index 7c4a9978..f067590a 100644
--- a/include/boost/core/ignore_unused.hpp
+++ b/include/boost/core/ignore_unused.hpp
@@ -7,6 +7,15 @@
 #ifndef BOOST_CORE_IGNORE_UNUSED_HPP
 #define BOOST_CORE_IGNORE_UNUSED_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 namespace boost {
@@ -15,81 +24,81 @@ namespace boost {
 
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 
-template <typename... Ts>
+BOOST_CORE_MODULE_EXPORT template <typename... Ts>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(Ts&& ...)
 {}
 
 #else
 
-template <typename... Ts>
+BOOST_CORE_MODULE_EXPORT template <typename... Ts>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(Ts const& ...)
 {}
 
 #endif
 
-template <typename... Ts>
+BOOST_CORE_MODULE_EXPORT template <typename... Ts>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
 #else // !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
 
-template <typename T1>
+BOOST_CORE_MODULE_EXPORT template <typename T1>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&)
 {}
 
-template <typename T1>
+BOOST_CORE_MODULE_EXPORT template <typename T1>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&)
 {}
 
-template <typename T1, typename T2>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&)
 {}
 
-template <typename T1, typename T2>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&)
 {}
 
-template <typename T1, typename T2, typename T3>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&, T3&)
 {}
 
-template <typename T1, typename T2, typename T3>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&, T3 const&)
 {}
 
-template <typename T1, typename T2, typename T3, typename T4>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3, typename T4>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&, T3&, T4&)
 {}
 
-template <typename T1, typename T2, typename T3, typename T4>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3, typename T4>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&, T3 const&, T4 const&)
 {}
 
-template <typename T1, typename T2, typename T3, typename T4, typename T5>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3, typename T4, typename T5>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&, T3&, T4&, T5&)
 {}
 
-template <typename T1, typename T2, typename T3, typename T4, typename T5>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3, typename T4, typename T5>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&, T3 const&, T4 const&, T5 const&)
 {}
 
-template <typename T1>
+BOOST_CORE_MODULE_EXPORT template <typename T1>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
-template <typename T1, typename T2>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
-template <typename T1, typename T2, typename T3>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
-template <typename T1, typename T2, typename T3, typename T4>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3, typename T4>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
-template <typename T1, typename T2, typename T3, typename T4, typename T5>
+BOOST_CORE_MODULE_EXPORT template <typename T1, typename T2, typename T3, typename T4, typename T5>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
@@ -97,4 +106,6 @@ BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 
 } // namespace boost
 
+#endif
+
 #endif // BOOST_CORE_IGNORE_UNUSED_HPP
diff --git a/include/boost/core/invoke_swap.hpp b/include/boost/core/invoke_swap.hpp
index 80562895..988551d2 100644
--- a/include/boost/core/invoke_swap.hpp
+++ b/include/boost/core/invoke_swap.hpp
@@ -21,14 +21,21 @@
 // to avoid forming an infinite recursion when the arguments are not
 // swappable.
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/enable_if.hpp>
 #include <boost/config.hpp>
 #if __cplusplus >= 201103L || defined(BOOST_DINKUMWARE_STDLIB)
-#include <utility> // for std::swap (C++11)
+#include <boost/config/std/utility.hpp> // for std::swap (C++11)
 #else
-#include <algorithm> // for std::swap (C++98)
+#include <boost/config/std/algorithm.hpp> // for std::swap (C++98)
 #endif
-#include <cstddef> // for std::size_t
+#include <boost/config/std/cstddef.hpp> // for std::size_t
 
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #pragma once
@@ -76,7 +83,7 @@ inline void invoke_swap_impl(T (& left)[N], T (& right)[N])
 namespace boost {
 namespace core {
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_GPU_ENABLED
 inline typename enable_if_c< !::boost_swap_impl::is_const<T>::value >::type
 invoke_swap(T& left, T& right)
@@ -90,4 +97,6 @@ invoke_swap(T& left, T& right)
 
 #undef BOOST_CORE_SWAP_NOEXCEPT_IF
 
+#endif
+
 #endif // BOOST_CORE_INVOKE_SWAP_HPP
diff --git a/include/boost/core/launder.hpp b/include/boost/core/launder.hpp
index 9ec5e7ee..26fc0378 100644
--- a/include/boost/core/launder.hpp
+++ b/include/boost/core/launder.hpp
@@ -11,6 +11,13 @@
 //  Distributed under the Boost Software License, Version 1.0.
 //  https://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 #if defined(__has_builtin)
@@ -27,7 +34,7 @@
 
 #elif (BOOST_CXX_VERSION >= 201703L) && !defined(BOOST_CORE_HAS_BUILTIN_LAUNDER)
 
-#include <new>
+#include <boost/config/std/new.hpp>
 
 #if defined(__cpp_lib_launder)
 # define BOOST_CORE_HAS_STD_LAUNDER
@@ -42,21 +49,21 @@ namespace core
 
 #if defined(BOOST_CORE_HAS_BUILTIN_LAUNDER)
 
-template<class T> T* launder( T* p )
+BOOST_CORE_MODULE_EXPORT template<class T> T* launder( T* p )
 {
     return __builtin_launder( p );
 }
 
 #elif defined(BOOST_CORE_HAS_STD_LAUNDER)
 
-template<class T> T* launder( T* p )
+BOOST_CORE_MODULE_EXPORT template<class T> T* launder( T* p )
 {
     return std::launder( p );
 }
 
 #else
 
-template<class T> T* launder( T* p )
+BOOST_CORE_MODULE_EXPORT template<class T> T* launder( T* p )
 {
     return p;
 }
@@ -66,4 +73,6 @@ template<class T> T* launder( T* p )
 } // namespace core
 } // namespace boost
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_LAUNDER_HPP_INCLUDED
diff --git a/include/boost/core/lightweight_test.hpp b/include/boost/core/lightweight_test.hpp
index f786deb2..1a21600d 100644
--- a/include/boost/core/lightweight_test.hpp
+++ b/include/boost/core/lightweight_test.hpp
@@ -22,17 +22,14 @@
 //  http://www.boost.org/LICENSE_1_0.txt
 //
 
-#include <boost/core/detail/lwt_unattended.hpp>
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_LIGHTWEIGHT_TEST_HPP) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#  error "Please #include <boost/core/lightweight_test.hpp> in your module global fragment"
+#endif
+
+// Subset of includes required for exported macros
 #include <boost/current_function.hpp>
 #include <boost/config.hpp>
-#include <exception>
-#include <iostream>
-#include <iterator>
-#include <string>
-#include <cstdlib>
-#include <cstring>
-#include <cstddef>
-#include <cctype>
 
 //  IDE's like Visual Studio perform better if output goes to std::cout or
 //  some other stream, so allow user to configure output stream:
@@ -40,6 +37,23 @@
 # define BOOST_LIGHTWEIGHT_TEST_OSTREAM std::cerr
 #endif
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+// Note that we're guaranteed to not be in a purview here
+import boost.core;
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/core/detail/lwt_unattended.hpp>
+#include <boost/config/std/exception.hpp>
+#include <boost/config/std/iostream.hpp>
+#include <boost/config/std/iterator.hpp>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/cstdlib.hpp>
+#include <boost/config/std/cstring.hpp>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/config/std/cctype.hpp>
+
+
 namespace boost
 {
 namespace detail
@@ -49,12 +63,12 @@ class test_result
 {
 public:
 
-    test_result(): report_( false ), errors_( 0 )
+    inline test_result(): report_( false ), errors_( 0 )
     {
         core::detail::lwt_unattended();
     }
 
-    ~test_result()
+    inline ~test_result()
     {
         if( !report_ )
         {
@@ -63,12 +77,12 @@ class test_result
         }
     }
 
-    int& errors()
+    inline int& errors()
     {
         return errors_;
     }
 
-    void done()
+    inline void done()
     {
         report_ = true;
     }
@@ -79,6 +93,7 @@ class test_result
     int errors_;
 };
 
+BOOST_CORE_MODULE_EXPORT
 inline test_result& test_results()
 {
     static test_result instance;
@@ -90,6 +105,7 @@ inline int& test_errors()
     return test_results().errors();
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline bool test_impl(char const * expr, char const * file, int line, char const * function, bool v)
 {
     if( v )
@@ -107,6 +123,7 @@ inline bool test_impl(char const * expr, char const * file, int line, char const
     }
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline void error_impl(char const * msg, char const * file, int line, char const * function)
 {
     BOOST_LIGHTWEIGHT_TEST_OSTREAM
@@ -115,6 +132,7 @@ inline void error_impl(char const * msg, char const * file, int line, char const
     ++test_results().errors();
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline void throw_failed_impl(const char* expr, char const * excep, char const * file, int line, char const * function)
 {
    BOOST_LIGHTWEIGHT_TEST_OSTREAM
@@ -123,6 +141,7 @@ inline void throw_failed_impl(const char* expr, char const * excep, char const *
    ++test_results().errors();
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline void no_throw_failed_impl(const char* expr, const char* file, int line, const char* function)
 {
     BOOST_LIGHTWEIGHT_TEST_OSTREAM
@@ -131,6 +150,7 @@ inline void no_throw_failed_impl(const char* expr, const char* file, int line, c
    ++test_results().errors();
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline void no_throw_failed_impl(const char* expr, const char* what, const char* file, int line, const char* function)
 {
     BOOST_LIGHTWEIGHT_TEST_OSTREAM
@@ -219,37 +239,37 @@ inline std::string test_output_impl( char8_t const& v )
 
 // predicates
 
-struct lw_test_eq
+BOOST_CORE_MODULE_EXPORT struct lw_test_eq
 {
     template <typename T, typename U>
     bool operator()(const T& t, const U& u) const { return t == u; }
 };
 
-struct lw_test_ne
+BOOST_CORE_MODULE_EXPORT struct lw_test_ne
 {
     template <typename T, typename U>
     bool operator()(const T& t, const U& u) const { return t != u; }
 };
 
-struct lw_test_lt
+BOOST_CORE_MODULE_EXPORT struct lw_test_lt
 {
     template <typename T, typename U>
     bool operator()(const T& t, const U& u) const { return t < u; }
 };
 
-struct lw_test_le
+BOOST_CORE_MODULE_EXPORT struct lw_test_le
 {
     template <typename T, typename U>
     bool operator()(const T& t, const U& u) const { return t <= u; }
 };
 
-struct lw_test_gt
+BOOST_CORE_MODULE_EXPORT struct lw_test_gt
 {
     template <typename T, typename U>
     bool operator()(const T& t, const U& u) const { return t > u; }
 };
 
-struct lw_test_ge
+BOOST_CORE_MODULE_EXPORT struct lw_test_ge
 {
     template <typename T, typename U>
     bool operator()(const T& t, const U& u) const { return t >= u; }
@@ -294,6 +314,7 @@ inline char const * lwt_predicate_name( lw_test_ge const& )
 
 //
 
+BOOST_CORE_MODULE_EXPORT
 template<class BinaryPredicate, class T, class U>
 inline bool test_with_impl(BinaryPredicate pred, char const * expr1, char const * expr2,
                            char const * file, int line, char const * function,
@@ -315,6 +336,7 @@ inline bool test_with_impl(BinaryPredicate pred, char const * expr1, char const
     }
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline bool test_cstr_eq_impl( char const * expr1, char const * expr2,
   char const * file, int line, char const * function, char const * const t, char const * const u )
 {
@@ -333,6 +355,7 @@ inline bool test_cstr_eq_impl( char const * expr1, char const * expr2,
     }
 }
 
+BOOST_CORE_MODULE_EXPORT
 inline bool test_cstr_ne_impl( char const * expr1, char const * expr2,
   char const * file, int line, char const * function, char const * const t, char const * const u )
 {
@@ -351,6 +374,7 @@ inline bool test_cstr_ne_impl( char const * expr1, char const * expr2,
     }
 }
 
+BOOST_CORE_MODULE_EXPORT
 template<class FormattedOutputFunction, class InputIterator1, class InputIterator2>
 bool test_all_eq_impl(FormattedOutputFunction& output,
                       char const * file, int line, char const * function,
@@ -421,6 +445,7 @@ bool test_all_eq_impl(FormattedOutputFunction& output,
     }
 }
 
+BOOST_CORE_MODULE_EXPORT
 template<class FormattedOutputFunction, class InputIterator1, class InputIterator2, typename BinaryPredicate>
 bool test_all_with_impl(FormattedOutputFunction& output,
                         char const * file, int line, char const * function,
@@ -504,6 +529,7 @@ bool test_all_with_impl(FormattedOutputFunction& output,
 
 } // namespace detail
 
+BOOST_CORE_MODULE_EXPORT
 inline int report_errors()
 {
     boost::detail::test_result& result = boost::detail::test_results();
@@ -529,6 +555,7 @@ inline int report_errors()
 namespace core
 {
 
+BOOST_CORE_MODULE_EXPORT
 inline void lwt_init()
 {
     boost::detail::test_results();
@@ -537,6 +564,11 @@ inline void lwt_init()
 } // namespace core
 } // namespace boost
 
+#endif // defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+// Macros should be defined by this header regardless of whether
+// modules are being used or not
+
 #define BOOST_TEST(expr) ( ::boost::detail::test_impl(#expr, __FILE__, __LINE__, BOOST_CURRENT_FUNCTION, (expr)? true: false) )
 #define BOOST_TEST_NOT(expr) BOOST_TEST(!(expr))
 
diff --git a/include/boost/core/lightweight_test_trait.hpp b/include/boost/core/lightweight_test_trait.hpp
index eea23717..1d4f996d 100644
--- a/include/boost/core/lightweight_test_trait.hpp
+++ b/include/boost/core/lightweight_test_trait.hpp
@@ -20,17 +20,29 @@
 // See accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt
 
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_LIGHTWEIGHT_TEST_TRAIT_HPP) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#  error "Please #include <boost/core/lightweight_test_trait.hpp> in your module global fragment"
+#endif
+
+// Subset of includes required for exported macros
 #include <boost/core/lightweight_test.hpp>
+#include <boost/config.hpp>
+
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+// Note that we're guaranteed to not be in a purview here
+import boost.core;
+#else
+
 #include <boost/core/type_name.hpp>
 #include <boost/core/detail/is_same.hpp>
-#include <boost/config.hpp>
 
 namespace boost
 {
 namespace detail
 {
 
-template< class T > inline void test_trait_impl( char const * trait, void (*)( T ),
+BOOST_CORE_MODULE_EXPORT template< class T > inline void test_trait_impl( char const * trait, void (*)( T ),
   bool expected, char const * file, int line, char const * function )
 {
     if( T::value == expected )
@@ -50,12 +62,12 @@ template< class T > inline void test_trait_impl( char const * trait, void (*)( T
     }
 }
 
-template<class T> inline bool test_trait_same_impl_( T )
+BOOST_CORE_MODULE_EXPORT template<class T> inline bool test_trait_same_impl_( T )
 {
     return T::value;
 }
 
-template<class T1, class T2> inline void test_trait_same_impl( char const * types,
+BOOST_CORE_MODULE_EXPORT template<class T1, class T2> inline void test_trait_same_impl( char const * types,
   boost::core::detail::is_same<T1, T2> same, char const * file, int line, char const * function )
 {
     if( test_trait_same_impl_( same ) )
@@ -78,6 +90,11 @@ template<class T1, class T2> inline void test_trait_same_impl( char const * type
 } // namespace detail
 } // namespace boost
 
+#endif // defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+// Macros should be defined by this header regardless of whether
+// modules are being used or not
+
 #define BOOST_TEST_TRAIT_TRUE(type) ( ::boost::detail::test_trait_impl(#type, (void(*)type)0, true, __FILE__, __LINE__, BOOST_CURRENT_FUNCTION) )
 #define BOOST_TEST_TRAIT_FALSE(type) ( ::boost::detail::test_trait_impl(#type, (void(*)type)0, false, __FILE__, __LINE__, BOOST_CURRENT_FUNCTION) )
 
diff --git a/include/boost/core/make_span.hpp b/include/boost/core/make_span.hpp
index 5f5df563..957c0b66 100644
--- a/include/boost/core/make_span.hpp
+++ b/include/boost/core/make_span.hpp
@@ -8,46 +8,53 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_MAKE_SPAN_HPP
 #define BOOST_CORE_MAKE_SPAN_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/span.hpp>
 
 namespace boost {
 
-template<class I>
+BOOST_CORE_MODULE_EXPORT template<class I>
 inline constexpr span<I>
 make_span(I* f, std::size_t c) noexcept
 {
     return span<I>(f, c);
 }
 
-template<class I>
+BOOST_CORE_MODULE_EXPORT template<class I>
 inline constexpr span<I>
 make_span(I* f, I* l) noexcept
 {
     return span<I>(f, l);
 }
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 inline constexpr span<T, N>
 make_span(T(&a)[N]) noexcept
 {
     return span<T, N>(a);
 }
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 inline constexpr span<T, N>
 make_span(std::array<T, N>& a) noexcept
 {
     return span<T, N>(a);
 }
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 inline constexpr span<const T, N>
 make_span(const std::array<T, N>& a) noexcept
 {
     return span<const T, N>(a);
 }
 
-template<class R>
+BOOST_CORE_MODULE_EXPORT template<class R>
 inline span<typename detail::span_data<R>::type>
 make_span(R&& r)
 {
@@ -57,3 +64,5 @@ make_span(R&& r)
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/max_align.hpp b/include/boost/core/max_align.hpp
index a5806d4b..829d5b0b 100644
--- a/include/boost/core/max_align.hpp
+++ b/include/boost/core/max_align.hpp
@@ -11,9 +11,17 @@
 //  Distributed under the Boost Software License, Version 1.0.
 //  https://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+
 #include <boost/core/alignof.hpp>
 #include <boost/config.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/core/detail/modules.hpp>
 
 // BOOST_CORE_HAS_FLOAT128
 
@@ -38,7 +46,7 @@ namespace boost
 namespace core
 {
 
-union max_align_t
+BOOST_CORE_MODULE_EXPORT union max_align_t
 {
     char c;
     short s;
@@ -74,9 +82,11 @@ union max_align_t
     void (max_align_t::*pmf)();
 };
 
-BOOST_CONSTEXPR_OR_CONST std::size_t max_align = BOOST_CORE_ALIGNOF( max_align_t );
+BOOST_CORE_MODULE_EXPORT BOOST_CONSTEXPR_OR_CONST std::size_t max_align = BOOST_CORE_ALIGNOF( max_align_t );
 
 } // namespace core
 } // namespace boost
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_MAX_ALIGN_HPP_INCLUDED
diff --git a/include/boost/core/memory_resource.hpp b/include/boost/core/memory_resource.hpp
index 0432f6f9..76265c88 100644
--- a/include/boost/core/memory_resource.hpp
+++ b/include/boost/core/memory_resource.hpp
@@ -11,10 +11,17 @@
 //  Distributed under the Boost Software License, Version 1.0.
 //  https://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
 #include <boost/core/max_align.hpp>
 #include <boost/config.hpp>
 #include <boost/config/workaround.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/core/detail/modules.hpp>
 
 // Define our own placement new to avoid the inclusion of <new>
 // (~9K extra lines) at Ion Gaztanhaga's request.
@@ -52,7 +59,7 @@ namespace boost
 namespace core
 {
 
-class memory_resource
+BOOST_CORE_MODULE_EXPORT class memory_resource
 {
 public:
 
@@ -66,7 +73,7 @@ class memory_resource
 
 #endif
 
-    BOOST_ATTRIBUTE_NODISCARD void* allocate( std::size_t bytes, std::size_t alignment = max_align )
+    BOOST_ATTRIBUTE_NODISCARD inline void* allocate( std::size_t bytes, std::size_t alignment = max_align )
     {
         // https://github.com/boostorg/container/issues/199
         // https://cplusplus.github.io/LWG/issue3471
@@ -74,12 +81,12 @@ class memory_resource
         return ::operator new( bytes, do_allocate( bytes, alignment ), core::detail::placement_new_tag() );
     }
 
-    void deallocate( void* p, std::size_t bytes, std::size_t alignment = max_align )
+    inline void deallocate( void* p, std::size_t bytes, std::size_t alignment = max_align )
     {
         do_deallocate( p, bytes, alignment );
     }
 
-    bool is_equal( memory_resource const & other ) const BOOST_NOEXCEPT
+    inline bool is_equal( memory_resource const & other ) const BOOST_NOEXCEPT
     {
         return do_is_equal( other );
     }
@@ -92,12 +99,12 @@ class memory_resource
     virtual bool do_is_equal( memory_resource const & other ) const BOOST_NOEXCEPT = 0;
 };
 
-inline bool operator==( memory_resource const& a, memory_resource const& b ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT inline bool operator==( memory_resource const& a, memory_resource const& b ) BOOST_NOEXCEPT
 {
     return &a == &b || a.is_equal( b );
 }
 
-inline bool operator!=( memory_resource const& a, memory_resource const& b ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT inline bool operator!=( memory_resource const& a, memory_resource const& b ) BOOST_NOEXCEPT
 {
     return !( a == b );
 }
@@ -105,4 +112,6 @@ inline bool operator!=( memory_resource const& a, memory_resource const& b ) BOO
 } // namespace core
 } // namespace boost
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_MEMORY_RESOURCE_HPP_INCLUDED
diff --git a/include/boost/core/no_exceptions_support.hpp b/include/boost/core/no_exceptions_support.hpp
index 1278e856..fa524230 100644
--- a/include/boost/core/no_exceptions_support.hpp
+++ b/include/boost/core/no_exceptions_support.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_NO_EXCEPTIONS_SUPPORT_HPP)
+#  error "Please #include <boost/core/no_exceptions_support.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_NO_EXCEPTIONS_SUPPORT_HPP
 #define BOOST_CORE_NO_EXCEPTIONS_SUPPORT_HPP
 
diff --git a/include/boost/core/noinit_adaptor.hpp b/include/boost/core/noinit_adaptor.hpp
index 623e3ea4..b929230c 100644
--- a/include/boost/core/noinit_adaptor.hpp
+++ b/include/boost/core/noinit_adaptor.hpp
@@ -8,11 +8,18 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_NOINIT_ADAPTOR_HPP
 #define BOOST_CORE_NOINIT_ADAPTOR_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/allocator_access.hpp>
 
 namespace boost {
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 struct noinit_adaptor
     : A {
     typedef void _default_construct_destroy;
@@ -62,7 +69,7 @@ struct noinit_adaptor
     }
 };
 
-template<class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class T, class U>
 inline bool
 operator==(const noinit_adaptor<T>& lhs,
     const noinit_adaptor<U>& rhs) BOOST_NOEXCEPT
@@ -70,7 +77,7 @@ operator==(const noinit_adaptor<T>& lhs,
     return static_cast<const T&>(lhs) == static_cast<const U&>(rhs);
 }
 
-template<class T, class U>
+BOOST_CORE_MODULE_EXPORT template<class T, class U>
 inline bool
 operator!=(const noinit_adaptor<T>& lhs,
     const noinit_adaptor<U>& rhs) BOOST_NOEXCEPT
@@ -78,7 +85,7 @@ operator!=(const noinit_adaptor<T>& lhs,
     return !(lhs == rhs);
 }
 
-template<class A>
+BOOST_CORE_MODULE_EXPORT template<class A>
 inline noinit_adaptor<A>
 noinit_adapt(const A& a) BOOST_NOEXCEPT
 {
@@ -88,3 +95,5 @@ noinit_adapt(const A& a) BOOST_NOEXCEPT
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/noncopyable.hpp b/include/boost/core/noncopyable.hpp
index 4ec2d54f..a21197c4 100644
--- a/include/boost/core/noncopyable.hpp
+++ b/include/boost/core/noncopyable.hpp
@@ -9,6 +9,15 @@
 #ifndef BOOST_CORE_NONCOPYABLE_HPP
 #define BOOST_CORE_NONCOPYABLE_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 namespace boost {
@@ -56,8 +65,10 @@ namespace noncopyable_  // protection from unintended ADL
   };
 }
 
-typedef noncopyable_::noncopyable noncopyable;
+BOOST_CORE_MODULE_EXPORT typedef noncopyable_::noncopyable noncopyable;
 
 } // namespace boost
 
+#endif
+
 #endif  // BOOST_CORE_NONCOPYABLE_HPP
diff --git a/include/boost/core/null_deleter.hpp b/include/boost/core/null_deleter.hpp
index 08b6a3d4..f33528b5 100644
--- a/include/boost/core/null_deleter.hpp
+++ b/include/boost/core/null_deleter.hpp
@@ -19,6 +19,13 @@
 #ifndef BOOST_CORE_NULL_DELETER_HPP
 #define BOOST_CORE_NULL_DELETER_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 #ifdef BOOST_HAS_PRAGMA_ONCE
@@ -31,7 +38,7 @@ namespace boost {
 namespace null_deleter_ns {
 
 //! A function object that does nothing and can be used as an empty deleter for \c shared_ptr
-struct null_deleter
+BOOST_CORE_MODULE_EXPORT struct null_deleter
 {
     //! Function object result type
     typedef void result_type;
@@ -44,8 +51,10 @@ struct null_deleter
 
 } // namespace null_deleter_ns
 
-using null_deleter_ns::null_deleter;
+BOOST_CORE_MODULE_EXPORT using null_deleter_ns::null_deleter;
 
 } // namespace boost
 
+#endif
+
 #endif // BOOST_CORE_NULL_DELETER_HPP
diff --git a/include/boost/core/nvp.hpp b/include/boost/core/nvp.hpp
index 8826a592..c233e1b6 100644
--- a/include/boost/core/nvp.hpp
+++ b/include/boost/core/nvp.hpp
@@ -8,13 +8,20 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_NVP_HPP
 #define BOOST_CORE_NVP_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/addressof.hpp>
 #include <boost/config.hpp>
 
 namespace boost {
 namespace serialization {
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 class nvp {
 public:
     nvp(const char* n, T& v) BOOST_NOEXCEPT
@@ -38,7 +45,7 @@ class nvp {
     T* v_;
 };
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 inline const nvp<T>
 make_nvp(const char* n, T& v) BOOST_NOEXCEPT
 {
@@ -47,11 +54,14 @@ make_nvp(const char* n, T& v) BOOST_NOEXCEPT
 
 } /* serialization */
 
-using serialization::nvp;
-using serialization::make_nvp;
+BOOST_CORE_MODULE_EXPORT using serialization::nvp;
+BOOST_CORE_MODULE_EXPORT using serialization::make_nvp;
 
 } /* boost */
 
+#endif // defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+// Export the macro even in builds with modules
 #define BOOST_NVP(v) boost::make_nvp(BOOST_STRINGIZE(v), v)
 
 #endif
diff --git a/include/boost/core/pointer_in_range.hpp b/include/boost/core/pointer_in_range.hpp
index 4957ff85..74a84514 100644
--- a/include/boost/core/pointer_in_range.hpp
+++ b/include/boost/core/pointer_in_range.hpp
@@ -9,7 +9,6 @@ Distributed under the Boost Software License, Version 1.0.
 #define BOOST_CORE_POINTER_IN_RANGE_HPP
 
 #include <boost/config.hpp>
-#include <functional>
 
 #if !defined(BOOST_NO_CXX14_CONSTEXPR)
 #if defined(BOOST_MSVC) && BOOST_MSVC >= 1925
@@ -25,9 +24,18 @@ Distributed under the Boost Software License, Version 1.0.
 #define BOOST_CORE_NO_CONSTEXPR_POINTER_IN_RANGE
 #endif
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/config/std/functional.hpp>
+
 namespace boost {
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 inline BOOST_CONSTEXPR bool
 pointer_in_range(const T* p, const T* b, const T* e)
 {
@@ -46,4 +54,6 @@ pointer_in_range(const T* p, const T* b, const T* e)
 
 } /* boost */
 
+#endif // defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
 #endif
diff --git a/include/boost/core/pointer_traits.hpp b/include/boost/core/pointer_traits.hpp
index 7de7a8e9..3a827143 100644
--- a/include/boost/core/pointer_traits.hpp
+++ b/include/boost/core/pointer_traits.hpp
@@ -8,9 +8,16 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_POINTER_TRAITS_HPP
 #define BOOST_CORE_POINTER_TRAITS_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 #include <boost/core/addressof.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost {
 namespace detail {
@@ -209,7 +216,7 @@ struct ptr_traits<T, ptr_none> { };
 
 } /* detail */
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 struct pointer_traits
     : detail::ptr_traits<T, typename detail::ptr_element<T>::type> { };
 
@@ -231,7 +238,7 @@ struct pointer_traits<T*>
 #endif
 };
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 BOOST_CONSTEXPR inline T*
 to_address(T* v) BOOST_NOEXCEPT
 {
@@ -265,14 +272,14 @@ ptr_address(const T& v, long) BOOST_NOEXCEPT
 
 } /* detail */
 
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 inline auto
 to_address(const T& v) BOOST_NOEXCEPT
 {
     return boost::detail::ptr_address(v, 0);
 }
 #else
-template<class T>
+BOOST_CORE_MODULE_EXPORT template<class T>
 inline typename pointer_traits<T>::element_type*
 to_address(const T& v) BOOST_NOEXCEPT
 {
@@ -283,3 +290,5 @@ to_address(const T& v) BOOST_NOEXCEPT
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/quick_exit.hpp b/include/boost/core/quick_exit.hpp
index ff1bda36..48d30a06 100644
--- a/include/boost/core/quick_exit.hpp
+++ b/include/boost/core/quick_exit.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_QUICK_EXIT_HPP_INCLUDED)
+#  error "Please #include <boost/core/quick_exit.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_QUICK_EXIT_HPP_INCLUDED
 #define BOOST_CORE_QUICK_EXIT_HPP_INCLUDED
 
diff --git a/include/boost/core/ref.hpp b/include/boost/core/ref.hpp
index d29a4d6f..012735e7 100644
--- a/include/boost/core/ref.hpp
+++ b/include/boost/core/ref.hpp
@@ -1,6 +1,13 @@
 #ifndef BOOST_CORE_REF_HPP
 #define BOOST_CORE_REF_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 #include <boost/config/workaround.hpp>
 #include <boost/core/addressof.hpp>
@@ -78,7 +85,7 @@ struct ref_empty
  usually allows the function templates to work on references
  unmodified.
 */
-template<class T> class reference_wrapper
+BOOST_CORE_MODULE_EXPORT template<class T> class reference_wrapper
 {
 public:
     /**
@@ -172,7 +179,7 @@ template<class T> class reference_wrapper
  @return `reference_wrapper<T>(t)`
  @remark Does not throw.
 */
-template<class T> BOOST_FORCEINLINE reference_wrapper<T> BOOST_REF_CONST ref( T & t ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> BOOST_FORCEINLINE reference_wrapper<T> BOOST_REF_CONST ref( T & t ) BOOST_NOEXCEPT
 {
 #if defined( BOOST_MSVC ) && BOOST_WORKAROUND( BOOST_MSVC, == 1600 )
 
@@ -191,7 +198,7 @@ template<class T> BOOST_FORCEINLINE reference_wrapper<T> BOOST_REF_CONST ref( T
  @return `reference_wrapper<T const>(t)`
  @remark Does not throw.
 */
-template<class T> BOOST_FORCEINLINE reference_wrapper<T const> BOOST_REF_CONST cref( T const & t ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> BOOST_FORCEINLINE reference_wrapper<T const> BOOST_REF_CONST cref( T const & t ) BOOST_NOEXCEPT
 {
     return reference_wrapper<T const>(t);
 }
@@ -215,12 +222,12 @@ template<class T> BOOST_FORCEINLINE reference_wrapper<T const> BOOST_REF_CONST c
 /**
  @remark Construction from a temporary object is disabled.
 */
-template<class T> void ref(T const&&) BOOST_REF_DELETE;
+BOOST_CORE_MODULE_EXPORT template<class T> void ref(T const&&) BOOST_REF_DELETE;
 
 /**
  @remark Construction from a temporary object is disabled.
 */
-template<class T> void cref(T const&&) BOOST_REF_DELETE;
+BOOST_CORE_MODULE_EXPORT template<class T> void cref(T const&&) BOOST_REF_DELETE;
 
 #undef BOOST_REF_DELETE
 
@@ -235,7 +242,7 @@ template<class T> void cref(T const&&) BOOST_REF_DELETE;
  The value static constant will be true if the type `T` is a
  specialization of `reference_wrapper`.
 */
-template<typename T> struct is_reference_wrapper
+BOOST_CORE_MODULE_EXPORT template<typename T> struct is_reference_wrapper
 {
     BOOST_STATIC_CONSTANT( bool, value = false );
 };
@@ -280,7 +287,7 @@ template<typename T> struct is_reference_wrapper< reference_wrapper<T> const vol
  The `typedef` type is `T::type` if `T` is a
  `reference_wrapper`, `T` otherwise.
 */
-template<typename T> struct unwrap_reference
+BOOST_CORE_MODULE_EXPORT template<typename T> struct unwrap_reference
 {
     typedef T type;
 };
@@ -322,7 +329,7 @@ template<typename T> struct unwrap_reference< reference_wrapper<T> const volatil
  @return `unwrap_reference<T>::type&(t)`
  @remark Does not throw.
 */
-template<class T> BOOST_FORCEINLINE typename unwrap_reference<T>::type& unwrap_ref( T & t ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> BOOST_FORCEINLINE typename unwrap_reference<T>::type& unwrap_ref( T & t ) BOOST_NOEXCEPT
 {
     return t;
 }
@@ -332,7 +339,7 @@ template<class T> BOOST_FORCEINLINE typename unwrap_reference<T>::type& unwrap_r
 /**
  @cond
 */
-template<class T> BOOST_FORCEINLINE T* get_pointer( reference_wrapper<T> const & r ) BOOST_NOEXCEPT
+BOOST_CORE_MODULE_EXPORT template<class T> BOOST_FORCEINLINE T* get_pointer( reference_wrapper<T> const & r ) BOOST_NOEXCEPT
 {
     return r.get_pointer();
 }
@@ -342,4 +349,6 @@ template<class T> BOOST_FORCEINLINE T* get_pointer( reference_wrapper<T> const &
 
 } // namespace boost
 
+#endif
+
 #endif // #ifndef BOOST_CORE_REF_HPP
diff --git a/include/boost/core/scoped_enum.hpp b/include/boost/core/scoped_enum.hpp
index 9267455d..97375f2a 100644
--- a/include/boost/core/scoped_enum.hpp
+++ b/include/boost/core/scoped_enum.hpp
@@ -7,6 +7,11 @@
 //  Distributed under the Boost Software License, Version 1.0.
 //  See http://www.boost.org/LICENSE_1_0.txt
 
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_SCOPED_ENUM_HPP)
+#  error "Please #include <boost/core/scoped_enum.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_SCOPED_ENUM_HPP
 #define BOOST_CORE_SCOPED_ENUM_HPP
 
diff --git a/include/boost/core/serialization.hpp b/include/boost/core/serialization.hpp
index 9c78c582..f7dc6532 100644
--- a/include/boost/core/serialization.hpp
+++ b/include/boost/core/serialization.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_SERIALIZATION_HPP_INCLUDED)
+#  error "Please #include <boost/core/serialization.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_SERIALIZATION_HPP_INCLUDED
 #define BOOST_CORE_SERIALIZATION_HPP_INCLUDED
 
@@ -15,7 +20,7 @@
 // without including a Boost.Serialization header
 
 #include <boost/core/nvp.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost
 {
diff --git a/include/boost/core/size.hpp b/include/boost/core/size.hpp
index dd04daa1..98e05237 100644
--- a/include/boost/core/size.hpp
+++ b/include/boost/core/size.hpp
@@ -8,31 +8,40 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_SIZE_HPP
 #define BOOST_CORE_SIZE_HPP
 
-#include <iterator>
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
+#include <boost/config/std/iterator.hpp>
 
 // Note: MSVC doesn't define __cpp_lib_nonmember_container_access but supports the feature even in C++14 mode
 #if (defined(__cpp_lib_nonmember_container_access) && (__cpp_lib_nonmember_container_access >= 201411l)) || \
     (defined(_MSC_VER) && (_MSC_VER >= 1900))
 
 namespace boost {
-using std::size;
+BOOST_CORE_MODULE_EXPORT using std::size;
 } /* boost */
 
 #else // (defined(__cpp_lib_nonmember_container_access) ...
 
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 namespace boost {
 
 template<class C>
-inline constexpr auto
+BOOST_CORE_MODULE_EXPORT inline constexpr auto
 size(const C& c) noexcept(noexcept(c.size())) -> decltype(c.size())
 {
     return c.size();
 }
 
 template<class T, std::size_t N>
-inline constexpr std::size_t
+BOOST_CORE_MODULE_EXPORT inline constexpr std::size_t
 size(T(&)[N]) noexcept
 {
     return N;
@@ -43,3 +52,5 @@ size(T(&)[N]) noexcept
 #endif // (defined(__cpp_lib_nonmember_container_access) ...
 
 #endif
+
+#endif
diff --git a/include/boost/core/snprintf.hpp b/include/boost/core/snprintf.hpp
index 91e252b4..371342ca 100644
--- a/include/boost/core/snprintf.hpp
+++ b/include/boost/core/snprintf.hpp
@@ -13,6 +13,11 @@
  *         as well as \c wchar_t counterparts.
  */
 
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_SNPRINTF_HPP_INCLUDED_)
+#  error "Please #include <boost/core/snprintf.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_SNPRINTF_HPP_INCLUDED_
 #define BOOST_CORE_SNPRINTF_HPP_INCLUDED_
 
diff --git a/include/boost/core/span.hpp b/include/boost/core/span.hpp
index 01446596..bcfc57cf 100644
--- a/include/boost/core/span.hpp
+++ b/include/boost/core/span.hpp
@@ -8,17 +8,26 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_SPAN_HPP
 #define BOOST_CORE_SPAN_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/detail/assert.hpp>
 #include <boost/core/data.hpp>
-#include <array>
-#include <iterator>
-#include <type_traits>
+#include <boost/config/std/array.hpp>
+#include <boost/config/std/iterator.hpp>
+#include <boost/config/std/type_traits.hpp>
 
 namespace boost {
 
-constexpr std::size_t dynamic_extent = static_cast<std::size_t>(-1);
+BOOST_CORE_MODULE_EXPORT constexpr std::size_t dynamic_extent = static_cast<std::size_t>(-1);
 
-template<class T, std::size_t E = dynamic_extent>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t E = dynamic_extent>
 class span;
 
 namespace detail {
@@ -368,27 +377,27 @@ constexpr std::size_t span<T, E>::extent;
 #endif
 
 #ifdef __cpp_deduction_guides
-template<class I, class L>
+BOOST_CORE_MODULE_EXPORT template<class I, class L>
 span(I*, L) -> span<I>;
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 span(T(&)[N]) -> span<T, N>;
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 span(std::array<T, N>&) -> span<T, N>;
 
-template<class T, std::size_t N>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t N>
 span(const std::array<T, N>&) -> span<const T, N>;
 
-template<class R>
+BOOST_CORE_MODULE_EXPORT template<class R>
 span(R&&) -> span<typename detail::span_data<R>::type>;
 
-template<class T, std::size_t E>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t E>
 span(span<T, E>) -> span<T, E>;
 #endif
 
 #ifdef __cpp_lib_byte
-template<class T, std::size_t E>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t E>
 inline span<const std::byte, detail::span_bytes<T, E>::value>
 as_bytes(span<T, E> s) noexcept
 {
@@ -397,7 +406,7 @@ as_bytes(span<T, E> s) noexcept
             s.size_bytes());
 }
 
-template<class T, std::size_t E>
+BOOST_CORE_MODULE_EXPORT template<class T, std::size_t E>
 inline typename std::enable_if<!std::is_const<T>::value,
     span<std::byte, detail::span_bytes<T, E>::value> >::type
 as_writable_bytes(span<T, E> s) noexcept
@@ -410,3 +419,5 @@ as_writable_bytes(span<T, E> s) noexcept
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/type_name.hpp b/include/boost/core/type_name.hpp
index 81e00c20..834383cf 100644
--- a/include/boost/core/type_name.hpp
+++ b/include/boost/core/type_name.hpp
@@ -7,24 +7,33 @@
 # pragma once
 #endif
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+
+#else
+
 // std::string boost::core::type_name<T>()
 //
 // Copyright 2021 Peter Dimov
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/demangle.hpp>
 #include <boost/config.hpp>
-#include <string>
-#include <functional>
-#include <memory>
-#include <utility>
-#include <cstdio>
-#include <cstddef>
-#include <cstring>
-#include <iosfwd>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/functional.hpp>
+#include <boost/config/std/memory.hpp>
+#include <boost/config/std/utility.hpp>
+#include <boost/config/std/cstdio.hpp>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/config/std/cstring.hpp>
+#include <boost/config/std/iosfwd.hpp>
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 
 namespace boost
@@ -232,7 +241,7 @@ template<class T> struct tn_holder
 
 template<> struct tn_holder<bool>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "bool" + suffix;
     }
@@ -240,7 +249,7 @@ template<> struct tn_holder<bool>
 
 template<> struct tn_holder<char>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "char" + suffix;
     }
@@ -248,7 +257,7 @@ template<> struct tn_holder<char>
 
 template<> struct tn_holder<signed char>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "signed char" + suffix;
     }
@@ -256,7 +265,7 @@ template<> struct tn_holder<signed char>
 
 template<> struct tn_holder<unsigned char>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "unsigned char" + suffix;
     }
@@ -264,7 +273,7 @@ template<> struct tn_holder<unsigned char>
 
 template<> struct tn_holder<short>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "short" + suffix;
     }
@@ -272,7 +281,7 @@ template<> struct tn_holder<short>
 
 template<> struct tn_holder<unsigned short>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "unsigned short" + suffix;
     }
@@ -280,7 +289,7 @@ template<> struct tn_holder<unsigned short>
 
 template<> struct tn_holder<int>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "int" + suffix;
     }
@@ -288,7 +297,7 @@ template<> struct tn_holder<int>
 
 template<> struct tn_holder<unsigned>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "unsigned" + suffix;
     }
@@ -296,7 +305,7 @@ template<> struct tn_holder<unsigned>
 
 template<> struct tn_holder<long>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "long" + suffix;
     }
@@ -304,7 +313,7 @@ template<> struct tn_holder<long>
 
 template<> struct tn_holder<unsigned long>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "unsigned long" + suffix;
     }
@@ -312,7 +321,7 @@ template<> struct tn_holder<unsigned long>
 
 template<> struct tn_holder<boost::long_long_type>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "long long" + suffix;
     }
@@ -320,7 +329,7 @@ template<> struct tn_holder<boost::long_long_type>
 
 template<> struct tn_holder<boost::ulong_long_type>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "unsigned long long" + suffix;
     }
@@ -330,7 +339,7 @@ template<> struct tn_holder<boost::ulong_long_type>
 
 template<> struct tn_holder<boost::int128_type>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "__int128" + suffix;
     }
@@ -338,7 +347,7 @@ template<> struct tn_holder<boost::int128_type>
 
 template<> struct tn_holder<boost::uint128_type>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "unsigned __int128" + suffix;
     }
@@ -350,7 +359,7 @@ template<> struct tn_holder<boost::uint128_type>
 
 template<> struct tn_holder<wchar_t>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "wchar_t" + suffix;
     }
@@ -362,7 +371,7 @@ template<> struct tn_holder<wchar_t>
 
 template<> struct tn_holder<char16_t>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "char16_t" + suffix;
     }
@@ -374,7 +383,7 @@ template<> struct tn_holder<char16_t>
 
 template<> struct tn_holder<char32_t>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "char32_t" + suffix;
     }
@@ -386,7 +395,7 @@ template<> struct tn_holder<char32_t>
 
 template<> struct tn_holder<char8_t>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "char8_t" + suffix;
     }
@@ -398,7 +407,7 @@ template<> struct tn_holder<char8_t>
 
 template<> struct tn_holder<std::byte>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::byte" + suffix;
     }
@@ -410,7 +419,7 @@ template<> struct tn_holder<std::byte>
 
 template<> struct tn_holder<float>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "float" + suffix;
     }
@@ -418,7 +427,7 @@ template<> struct tn_holder<float>
 
 template<> struct tn_holder<double>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "double" + suffix;
     }
@@ -426,7 +435,7 @@ template<> struct tn_holder<double>
 
 template<> struct tn_holder<long double>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "long double" + suffix;
     }
@@ -436,7 +445,7 @@ template<> struct tn_holder<long double>
 
 template<> struct tn_holder<void>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "void" + suffix;
     }
@@ -448,7 +457,7 @@ template<> struct tn_holder<void>
 
 template<> struct tn_holder<std::nullptr_t>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::nullptr_t" + suffix;
     }
@@ -460,7 +469,7 @@ template<> struct tn_holder<std::nullptr_t>
 
 template<class T> struct tn_holder<T const>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return tn_holder<T>::type_name( " const" + suffix );
     }
@@ -468,7 +477,7 @@ template<class T> struct tn_holder<T const>
 
 template<class T> struct tn_holder<T volatile>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return tn_holder<T>::type_name( " volatile" + suffix );
     }
@@ -476,7 +485,7 @@ template<class T> struct tn_holder<T volatile>
 
 template<class T> struct tn_holder<T const volatile>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return tn_holder<T>::type_name( " const volatile" + suffix );
     }
@@ -486,7 +495,7 @@ template<class T> struct tn_holder<T const volatile>
 
 template<class T> struct tn_holder<T&>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return tn_holder<T>::type_name( "&" + suffix );
     }
@@ -496,7 +505,7 @@ template<class T> struct tn_holder<T&>
 
 template<class T> struct tn_holder<T&&>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return tn_holder<T>::type_name( "&&" + suffix );
     }
@@ -940,7 +949,7 @@ template<template<class Ch, class Tr, class A> class L, class Ch> struct tn_hold
 
 template<> struct tn_holder<std::string>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::string" + suffix;
     }
@@ -948,7 +957,7 @@ template<> struct tn_holder<std::string>
 
 template<> struct tn_holder<std::wstring>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::wstring" + suffix;
     }
@@ -958,7 +967,7 @@ template<> struct tn_holder<std::wstring>
 
 template<> struct tn_holder<std::u16string>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::u16string" + suffix;
     }
@@ -970,7 +979,7 @@ template<> struct tn_holder<std::u16string>
 
 template<> struct tn_holder<std::u32string>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::u32string" + suffix;
     }
@@ -982,7 +991,7 @@ template<> struct tn_holder<std::u32string>
 
 template<> struct tn_holder< std::basic_string<char8_t> >
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::u8string" + suffix;
     }
@@ -1004,7 +1013,7 @@ template<template<class Ch, class Tr> class L, class Ch> struct tn_holder< L<Ch,
 // needed for libstdc++
 template<> struct tn_holder<std::ostream>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::ostream" + suffix;
     }
@@ -1014,7 +1023,7 @@ template<> struct tn_holder<std::ostream>
 
 template<> struct tn_holder<std::string_view>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::string_view" + suffix;
     }
@@ -1022,7 +1031,7 @@ template<> struct tn_holder<std::string_view>
 
 template<> struct tn_holder<std::wstring_view>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::wstring_view" + suffix;
     }
@@ -1032,7 +1041,7 @@ template<> struct tn_holder<std::wstring_view>
 
 template<> struct tn_holder<std::u16string_view>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::u16string_view" + suffix;
     }
@@ -1044,7 +1053,7 @@ template<> struct tn_holder<std::u16string_view>
 
 template<> struct tn_holder<std::u32string_view>
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::u32string_view" + suffix;
     }
@@ -1056,7 +1065,7 @@ template<> struct tn_holder<std::u32string_view>
 
 template<> struct tn_holder< std::basic_string_view<char8_t> >
 {
-    static std::string type_name( std::string const& suffix )
+    static inline std::string type_name( std::string const& suffix )
     {
         return "std::u8string_view" + suffix;
     }
@@ -1175,7 +1184,7 @@ template<template<class T, std::size_t N> class L, class T, std::size_t N> struc
 
 } // namespace detail
 
-template<class T> std::string type_name()
+BOOST_CORE_MODULE_EXPORT template<class T> std::string type_name()
 {
     return core::detail::tn_holder<T>::type_name( "" );
 }
@@ -1183,4 +1192,6 @@ template<class T> std::string type_name()
 } // namespace core
 } // namespace boost
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_TYPE_NAME_HPP_INCLUDED
diff --git a/include/boost/core/typeinfo.hpp b/include/boost/core/typeinfo.hpp
index d33d29ba..049bd337 100644
--- a/include/boost/core/typeinfo.hpp
+++ b/include/boost/core/typeinfo.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_TYPEINFO_HPP_INCLUDED)
+#  error "Please #include <boost/core/type_info.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_TYPEINFO_HPP_INCLUDED
 #define BOOST_CORE_TYPEINFO_HPP_INCLUDED
 
@@ -20,8 +25,8 @@
 #if defined( BOOST_NO_TYPEID )
 
 #include <boost/current_function.hpp>
-#include <functional>
-#include <cstring>
+#include <boost/config/std/functional.hpp>
+#include <boost/config/std/cstring.hpp>
 
 namespace boost
 {
@@ -41,11 +46,11 @@ class typeinfo
 
 public:
 
-    typeinfo( char const * name, void (*lib_id)() ): name_( name ), lib_id_( lib_id )
+    inline typeinfo( char const * name, void (*lib_id)() ): name_( name ), lib_id_( lib_id )
     {
     }
 
-    bool operator==( typeinfo const& rhs ) const
+    inline bool operator==( typeinfo const& rhs ) const
     {
 #if ( defined(_WIN32) || defined(__CYGWIN__) ) && ( defined(__GNUC__) || defined(__clang__) ) && !defined(BOOST_DISABLE_CURRENT_FUNCTION)
 
@@ -58,12 +63,12 @@ class typeinfo
 #endif
     }
 
-    bool operator!=( typeinfo const& rhs ) const
+    inline bool operator!=( typeinfo const& rhs ) const
     {
         return !( *this == rhs );
     }
 
-    bool before( typeinfo const& rhs ) const
+    inline bool before( typeinfo const& rhs ) const
     {
 #if ( defined(_WIN32) || defined(__CYGWIN__) ) && ( defined(__GNUC__) || defined(__clang__) ) && !defined(BOOST_DISABLE_CURRENT_FUNCTION)
 
@@ -76,7 +81,7 @@ class typeinfo
 #endif
     }
 
-    char const* name() const
+    inline char const* name() const
     {
         return name_;
     }
@@ -133,7 +138,7 @@ template<class T> struct core_typeid_< T const volatile >: core_typeid_< T >
 #else
 
 #include <boost/core/demangle.hpp>
-#include <typeinfo>
+#include <boost/config/std/typeinfo.hpp>
 
 namespace boost
 {
diff --git a/include/boost/core/uncaught_exceptions.hpp b/include/boost/core/uncaught_exceptions.hpp
index 380e81cd..ad01d8b2 100644
--- a/include/boost/core/uncaught_exceptions.hpp
+++ b/include/boost/core/uncaught_exceptions.hpp
@@ -16,6 +16,11 @@
  * https://github.com/panaseleus/stack_unwinding/blob/master/boost/exception/uncaught_exception_count.hpp
  */
 
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_UNCAUGHT_EXCEPTIONS_HPP_INCLUDED_)
+#  error "Please #include <boost/core/uncaught_exceptions.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_UNCAUGHT_EXCEPTIONS_HPP_INCLUDED_
 #define BOOST_CORE_UNCAUGHT_EXCEPTIONS_HPP_INCLUDED_
 
diff --git a/include/boost/core/underlying_type.hpp b/include/boost/core/underlying_type.hpp
index 7ecba313..9d71981f 100644
--- a/include/boost/core/underlying_type.hpp
+++ b/include/boost/core/underlying_type.hpp
@@ -11,11 +11,18 @@
 #ifndef BOOST_CORE_UNDERLYING_TYPE_HPP
 #define BOOST_CORE_UNDERLYING_TYPE_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/config.hpp>
 
 // GCC 4.7 and later seem to provide std::underlying_type
 #if !defined(BOOST_NO_CXX11_HDR_TYPE_TRAITS) || (defined(BOOST_GCC) && BOOST_GCC >= 40700 && defined(__GXX_EXPERIMENTAL_CXX0X__))
-#include <type_traits>
+#include <boost/config/std/type_traits.hpp>
 #define BOOST_DETAIL_HAS_STD_UNDERLYING_TYPE
 #endif
 
@@ -68,7 +75,7 @@ struct underlying_type_impl
  * to deduce the underlying type of enums. The user is expected to specialize
  * this trait in this case.
  */
-template< typename EnumType >
+BOOST_CORE_MODULE_EXPORT template< typename EnumType >
 struct underlying_type :
     public detail::underlying_type_impl< EnumType >
 {
@@ -76,4 +83,6 @@ struct underlying_type :
 
 } // namespace boost
 
+#endif
+
 #endif  // BOOST_CORE_UNDERLYING_TYPE_HPP
diff --git a/include/boost/core/use_default.hpp b/include/boost/core/use_default.hpp
index 9d9be79d..0686dc52 100644
--- a/include/boost/core/use_default.hpp
+++ b/include/boost/core/use_default.hpp
@@ -8,10 +8,20 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_USE_DEFAULT_HPP
 #define BOOST_CORE_USE_DEFAULT_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+
 namespace boost {
 
-struct use_default { };
+BOOST_CORE_MODULE_EXPORT struct use_default { };
 
 } /* boost */
 
 #endif
+
+#endif
diff --git a/include/boost/core/verbose_terminate_handler.hpp b/include/boost/core/verbose_terminate_handler.hpp
index b6074703..c91d9cda 100644
--- a/include/boost/core/verbose_terminate_handler.hpp
+++ b/include/boost/core/verbose_terminate_handler.hpp
@@ -11,20 +11,28 @@
 //  Distributed under the Boost Software License, Version 1.0.
 //  https://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+
+#include <boost/core/detail/modules.hpp>
 #include <boost/core/demangle.hpp>
 #include <boost/throw_exception.hpp>
 #include <boost/config.hpp>
-#include <exception>
-#include <typeinfo>
-#include <cstdlib>
-#include <cstdio>
+#include <boost/config/std/exception.hpp>
+#include <boost/config/std/typeinfo.hpp>
+#include <boost/config/std/cstdlib.hpp>
+#include <boost/config/std/cstdio.hpp>
 
 namespace boost
 {
 namespace core
 {
 
-BOOST_NORETURN inline void verbose_terminate_handler()
+BOOST_CORE_MODULE_EXPORT BOOST_NORETURN inline void verbose_terminate_handler()
 {
     std::set_terminate( 0 );
 
@@ -85,4 +93,6 @@ BOOST_NORETURN inline void verbose_terminate_handler()
 } // namespace core
 } // namespace boost
 
+#endif
+
 #endif  // #ifndef BOOST_CORE_VERBOSE_TERMINATE_HANDLER_HPP_INCLUDED
diff --git a/include/boost/core/yield_primitives.hpp b/include/boost/core/yield_primitives.hpp
index 899453e5..de9aea44 100644
--- a/include/boost/core/yield_primitives.hpp
+++ b/include/boost/core/yield_primitives.hpp
@@ -1,3 +1,8 @@
+// Make the header safe to include from libraries supporting modules
+#if defined(BOOST_IN_MODULE_PURVIEW) && !defined(BOOST_CORE_YIELD_PRIMITIVES_HPP_INCLUDED)
+#  error "Please #include <boost/core/yield_primitives.hpp> in your module global fragment"
+#endif
+
 #ifndef BOOST_CORE_YIELD_PRIMITIVES_HPP_INCLUDED
 #define BOOST_CORE_YIELD_PRIMITIVES_HPP_INCLUDED
 
diff --git a/include/boost/get_pointer.hpp b/include/boost/get_pointer.hpp
index 36e2cd7d..4ec02da2 100644
--- a/include/boost/get_pointer.hpp
+++ b/include/boost/get_pointer.hpp
@@ -2,10 +2,18 @@
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
+
 #ifndef GET_POINTER_DWA20021219_HPP
 #define GET_POINTER_DWA20021219_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
 #include <boost/config.hpp>
+#include <boost/core/detail/modules.hpp>
 
 // In order to avoid circular dependencies with Boost.TR1
 // we make sure that our include of <memory> doesn't try to
@@ -17,7 +25,7 @@ namespace boost {
 
 // get_pointer(p) extracts a ->* capable pointer from p
 
-template<class T> T * get_pointer(T * p)
+BOOST_CORE_MODULE_EXPORT template<class T> T * get_pointer(T * p)
 {
     return p;
 }
@@ -45,7 +53,7 @@ template<class T> T * get_pointer(T * p)
 #define BOOST_CORE_DETAIL_DISABLED_DEPRECATED_WARNINGS
 #endif
 
-template<class T> T * get_pointer(std::auto_ptr<T> const& p)
+BOOST_CORE_MODULE_EXPORT template<class T> T * get_pointer(std::auto_ptr<T> const& p)
 {
     return p.get();
 }
@@ -59,12 +67,12 @@ template<class T> T * get_pointer(std::auto_ptr<T> const& p)
 
 #if !defined( BOOST_NO_CXX11_SMART_PTR )
 
-template<class T> T * get_pointer( std::unique_ptr<T> const& p )
+BOOST_CORE_MODULE_EXPORT template<class T> T * get_pointer( std::unique_ptr<T> const& p )
 {
     return p.get();
 }
 
-template<class T> T * get_pointer( std::shared_ptr<T> const& p )
+BOOST_CORE_MODULE_EXPORT template<class T> T * get_pointer( std::shared_ptr<T> const& p )
 {
     return p.get();
 }
@@ -73,4 +81,6 @@ template<class T> T * get_pointer( std::shared_ptr<T> const& p )
 
 } // namespace boost
 
+#endif
+
 #endif // GET_POINTER_DWA20021219_HPP
diff --git a/include/boost/is_placeholder.hpp b/include/boost/is_placeholder.hpp
index 5f1b544f..c9273a1d 100644
--- a/include/boost/is_placeholder.hpp
+++ b/include/boost/is_placeholder.hpp
@@ -7,7 +7,6 @@
 # pragma once
 #endif
 
-
 //  is_placeholder.hpp - TR1 is_placeholder metafunction
 //
 //  Copyright (c) 2006 Peter Dimov
@@ -17,15 +16,25 @@
 //  See accompanying file LICENSE_1_0.txt or copy at
 //  http://www.boost.org/LICENSE_1_0.txt
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+
 
 namespace boost
 {
 
-template< class T > struct is_placeholder
+BOOST_CORE_MODULE_EXPORT template< class T > struct is_placeholder
 {
     enum _vt { value = 0 };
 };
 
 } // namespace boost
 
+#endif
+
 #endif // #ifndef BOOST_IS_PLACEHOLDER_HPP_INCLUDED
diff --git a/include/boost/non_type.hpp b/include/boost/non_type.hpp
index 896aed4d..376a435a 100644
--- a/include/boost/non_type.hpp
+++ b/include/boost/non_type.hpp
@@ -11,17 +11,25 @@
 #ifndef BOOST_NON_TYPE_HPP_GP_20030417
 #define BOOST_NON_TYPE_HPP_GP_20030417
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 
 namespace boost {
 
   // Just a simple "envelope" for non-type template parameters. Useful
   // to work around some MSVC deficiencies.
 
- template <typename T, T n>
+ BOOST_CORE_MODULE_EXPORT template <typename T, T n>
  struct non_type { };
 
 
 }
 
+#endif
 
 #endif // include guard
diff --git a/include/boost/type.hpp b/include/boost/type.hpp
index ab81c916..a392d3e3 100644
--- a/include/boost/type.hpp
+++ b/include/boost/type.hpp
@@ -4,15 +4,25 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #ifndef BOOST_TYPE_DWA20010120_HPP
-# define BOOST_TYPE_DWA20010120_HPP
+#define BOOST_TYPE_DWA20010120_HPP
+
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
 
 namespace boost {
 
   // Just a simple "type envelope". Useful in various contexts, mostly to work
   // around some MSVC deficiencies.
-  template <class T>
+  BOOST_CORE_MODULE_EXPORT template <class T>
   struct type {};
 
 }
 
+#endif
+
 #endif // BOOST_TYPE_DWA20010120_HPP
diff --git a/include/boost/visit_each.hpp b/include/boost/visit_each.hpp
index 6463ca9c..3e7b4af3 100644
--- a/include/boost/visit_each.hpp
+++ b/include/boost/visit_each.hpp
@@ -6,22 +6,31 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 // For more information, see http://www.boost.org/libs/signals
-
 #ifndef BOOST_VISIT_EACH_HPP
 #define BOOST_VISIT_EACH_HPP
 
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_CORE_INTERFACE_UNIT)
+#ifndef BOOST_IN_MODULE_PURVIEW
+import boost.core;
+#endif
+#else
+
+#include <boost/core/detail/modules.hpp>
+
 namespace boost {
-  template<typename Visitor, typename T>
+  BOOST_CORE_MODULE_EXPORT template<typename Visitor, typename T>
   inline void visit_each(Visitor& visitor, const T& t, long)
   {
     visitor(t);
   }
 
-  template<typename Visitor, typename T>
+  BOOST_CORE_MODULE_EXPORT template<typename Visitor, typename T>
   inline void visit_each(Visitor& visitor, const T& t)
   {
     visit_each(visitor, t, 0);
   }
 }
 
+#endif
+
 #endif // BOOST_VISIT_EACH_HPP
diff --git a/modules/boost_core.cppm b/modules/boost_core.cppm
new file mode 100644
index 00000000..9cd55f17
--- /dev/null
+++ b/modules/boost_core.cppm
@@ -0,0 +1,82 @@
+module;
+
+#include <cmath> // FP_xxx macros. Must be before import std to avoid conflicts
+#include <stdio.h> // stderr. Must be before import std to avoid conflicts
+#include <boost/core/detail/demangle_cxxabi.hpp> // must be before import std to avoid conflicts
+#include <boost/core/detail/lwt_unattended.hpp>
+#if defined(_MSC_VER)
+#include <boost/core/detail/intrin.hpp>
+#endif
+#include <boost/core/alignof.hpp>
+#include <boost/assert.hpp>
+#include <boost/assert/source_location.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/throw_exception.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <boost/current_function.hpp>
+#include <boost/cstdint.hpp>
+
+export module boost.core;
+
+export import std; // re-exporting simplifies consuming lightweight_test
+
+#define BOOST_CORE_INTERFACE_UNIT
+#define BOOST_IN_MODULE_PURVIEW
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#endif
+
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 5244)
+#endif
+
+#include <boost/core/detail/is_same.hpp>
+#include <boost/core/detail/string_view.hpp>
+#include <boost/core/detail/splitmix64.hpp>
+#include <boost/core/demangle.hpp>
+#include <boost/core/enable_if.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/core/type_name.hpp>
+#include <boost/core/bit.hpp>
+#include <boost/core/addressof.hpp>
+#include <boost/core/data.hpp>
+#include <boost/core/size.hpp>
+#include <boost/core/span.hpp>
+#include <boost/core/make_span.hpp>
+#include <boost/core/cmath.hpp>
+#include <boost/core/checked_delete.hpp>
+#include <boost/core/default_allocator.hpp>
+#include <boost/core/exchange.hpp>
+#include <boost/core/first_scalar.hpp>
+#include <boost/core/functor.hpp>
+#include <boost/core/identity.hpp>
+#include <boost/core/ignore_unused.hpp>
+#include <boost/core/launder.hpp>
+#include <boost/core/max_align.hpp>
+#include <boost/core/memory_resource.hpp>
+#include <boost/core/noinit_adaptor.hpp>
+#include <boost/core/noncopyable.hpp>
+#include <boost/core/null_deleter.hpp>
+#include <boost/core/fclose_deleter.hpp>
+#include <boost/core/nvp.hpp>
+#include <boost/core/pointer_in_range.hpp>
+#include <boost/core/pointer_traits.hpp>
+#include <boost/core/ref.hpp>
+#include <boost/core/use_default.hpp>
+#include <boost/core/verbose_terminate_handler.hpp>
+#include <boost/core/allocator_access.hpp>
+#include <boost/core/allocator_traits.hpp>
+#include <boost/core/empty_value.hpp>
+#include <boost/core/invoke_swap.hpp>
+#include <boost/core/alloc_construct.hpp>
+#include <boost/core/underlying_type.hpp>
+#include <boost/is_placeholder.hpp>
+#include <boost/non_type.hpp>
+#include <boost/type.hpp>
+#include <boost/visit_each.hpp>
+#include <boost/get_pointer.hpp>
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index a6cdfdcc..aaa1f4f4 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -2,6 +2,10 @@
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt
 
+if(BOOST_USE_MODULES)
+set(CMAKE_CXX_MODULE_STD ON)
+endif()
+
 include(BoostTestJamfile OPTIONAL RESULT_VARIABLE HAVE_BOOST_TEST)
 
 if(HAVE_BOOST_TEST)
@@ -24,12 +28,16 @@ set(BOOST_TEST_LINK_LIBRARIES Boost::core Boost::config Boost::move Boost::smart
 
 boost_test(TYPE run SOURCES fclose_deleter_test.cpp)
 
+# The serialization tests require building Boost libraries not modularized yet,
+# which causes errors
+if (NOT BOOST_USE_MODULES)
 set(BOOST_TEST_LINK_LIBRARIES Boost::core Boost::serialization)
 
 boost_test(TYPE run SOURCES serialization_nvp_test.cpp)
 boost_test(TYPE run SOURCES serialization_split_free_test.cpp)
 boost_test(TYPE run SOURCES serialization_split_member_test.cpp)
 boost_test(TYPE run SOURCES serialization_construct_data_test.cpp)
+endif()
 
 set(THREADS_PREFER_PTHREAD_FLAG ON)
 find_package(Threads REQUIRED)
diff --git a/test/addressof_np_test.cpp b/test/addressof_np_test.cpp
index 6e8f7069..bb94b57f 100644
--- a/test/addressof_np_test.cpp
+++ b/test/addressof_np_test.cpp
@@ -8,7 +8,7 @@
 
 #include <boost/utility/addressof.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 #if defined( BOOST_NO_CXX11_NULLPTR )
 
diff --git a/test/addressof_test.cpp b/test/addressof_test.cpp
index bf75aca5..ffe49489 100644
--- a/test/addressof_test.cpp
+++ b/test/addressof_test.cpp
@@ -14,7 +14,7 @@
 #pragma warning(push, 3)
 #endif
 
-#include <iostream>
+#include <boost/config/std/iostream.hpp>
 
 #if defined(BOOST_MSVC) && (BOOST_MSVC < 1300)
 #pragma warning(pop)
diff --git a/test/addressof_test2.cpp b/test/addressof_test2.cpp
index 3ad48f43..97e82705 100644
--- a/test/addressof_test2.cpp
+++ b/test/addressof_test2.cpp
@@ -16,7 +16,7 @@
 #pragma warning(push, 3)
 #endif
 
-#include <iostream>
+#include <boost/config/std/iostream.hpp>
 
 #if defined(BOOST_MSVC) && (BOOST_MSVC < 1300)
 #pragma warning(pop)
diff --git a/test/alignof_test.cpp b/test/alignof_test.cpp
index 6468a79d..bc551151 100644
--- a/test/alignof_test.cpp
+++ b/test/alignof_test.cpp
@@ -2,11 +2,22 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/core/alignof.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/type_traits.hpp>
 #include <boost/config.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 template<class T> struct struct_of
 {
@@ -96,3 +107,5 @@ int main()
 
     return boost::report_errors();
 }
+
+#endif
\ No newline at end of file
diff --git a/test/allocator_max_size_test.cpp b/test/allocator_max_size_test.cpp
index b2837f11..3e337958 100644
--- a/test/allocator_max_size_test.cpp
+++ b/test/allocator_max_size_test.cpp
@@ -7,7 +7,7 @@ Distributed under the Boost Software License, Version 1.0.
 */
 #include <boost/core/allocator_access.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T>
 struct A1 {
diff --git a/test/allocator_pmr_test.cpp b/test/allocator_pmr_test.cpp
index 96def034..145a5203 100644
--- a/test/allocator_pmr_test.cpp
+++ b/test/allocator_pmr_test.cpp
@@ -12,7 +12,7 @@
 #include <boost/config.hpp>
 
 #ifndef BOOST_NO_CXX17_HDR_MEMORY_RESOURCE
-#include <memory_resource>
+#include <boost/config/std/memory_resource.hpp>
 
 void pmr_allocator_destroy_compiles(std::pmr::polymorphic_allocator<int>& alloc, int* p)
 {
diff --git a/test/allocator_size_type_test.cpp b/test/allocator_size_type_test.cpp
index 50301ca7..b09e93be 100644
--- a/test/allocator_size_type_test.cpp
+++ b/test/allocator_size_type_test.cpp
@@ -5,6 +5,18 @@ Copyright 2020 Glen Joseph Fernandes
 Distributed under the Boost Software License, Version 1.0.
 (http://www.boost.org/LICENSE_1_0.txt)
 */
+
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/core/allocator_access.hpp>
 #include <boost/core/lightweight_test_trait.hpp>
 #include <boost/type_traits/is_same.hpp>
@@ -36,3 +48,5 @@ int main()
 #endif
     return boost::report_errors();
 }
+
+#endif
diff --git a/test/bit_byteswap_test_cx.cpp b/test/bit_byteswap_test_cx.cpp
index 384d87b5..351d79fd 100644
--- a/test/bit_byteswap_test_cx.cpp
+++ b/test/bit_byteswap_test_cx.cpp
@@ -18,7 +18,7 @@ BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOS
 #else
 
 #include <boost/core/bit.hpp>
-#include <cstdint>
+#include <boost/config/std/cstdint.hpp>
 
 #define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
 
diff --git a/test/bit_cast_test.cpp b/test/bit_cast_test.cpp
index 3d3408ff..d8d7b07d 100644
--- a/test/bit_cast_test.cpp
+++ b/test/bit_cast_test.cpp
@@ -7,7 +7,7 @@
 #include <boost/core/bit.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/cstdint.hpp>
-#include <cstring>
+#include <boost/config/std/cstring.hpp>
 
 int main()
 {
diff --git a/test/bit_cast_test_cx.cpp b/test/bit_cast_test_cx.cpp
index 1f185350..336f5b45 100644
--- a/test/bit_cast_test_cx.cpp
+++ b/test/bit_cast_test_cx.cpp
@@ -14,7 +14,8 @@
 
 BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX11_CONSTEXPR is defined" )
 
-#elif !defined(BOOST_CORE_HAS_BUILTIN_BIT_CAST)
+// BOOST_CORE_HAS_BUILTIN_BIT_CAST is not public, but should be defined in every compiler that supports BOOST_USE_MODULES
+#elif !defined(BOOST_CORE_HAS_BUILTIN_BIT_CAST) && !defined(BOOST_USE_MODULES)
 
 BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_CORE_HAS_BUILTIN_BIT_CAST is not defined" )
 
diff --git a/test/bit_ceil_test.cpp b/test/bit_ceil_test.cpp
index 94cbfc00..fd9e9964 100644
--- a/test/bit_ceil_test.cpp
+++ b/test/bit_ceil_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_bit_ceil( T x )
 {
diff --git a/test/bit_countl_test.cpp b/test/bit_countl_test.cpp
index fe6e3b5b..7a9c4b33 100644
--- a/test/bit_countl_test.cpp
+++ b/test/bit_countl_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_countl( T x )
 {
diff --git a/test/bit_countr_test.cpp b/test/bit_countr_test.cpp
index ab9bd063..7dc117a9 100644
--- a/test/bit_countr_test.cpp
+++ b/test/bit_countr_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_countr( T x )
 {
diff --git a/test/bit_countr_test_cx.cpp b/test/bit_countr_test_cx.cpp
index 3548ac5f..1fa843be 100644
--- a/test/bit_countr_test_cx.cpp
+++ b/test/bit_countr_test_cx.cpp
@@ -22,7 +22,7 @@ BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOS
 #else
 
 #include <boost/core/bit.hpp>
-#include <climits>
+#include <boost/config/std/climits.hpp>
 
 #define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
 
diff --git a/test/bit_endian_test.cpp b/test/bit_endian_test.cpp
index 06f415ea..d60120a5 100644
--- a/test/bit_endian_test.cpp
+++ b/test/bit_endian_test.cpp
@@ -7,7 +7,7 @@
 #include <boost/core/bit.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/cstdint.hpp>
-#include <cstring>
+#include <boost/config/std/cstring.hpp>
 
 #if defined(_MSC_VER)
 # pragma warning(disable: 4127) // conditional expression is constant
diff --git a/test/bit_floor_test.cpp b/test/bit_floor_test.cpp
index 04dc720f..37961dca 100644
--- a/test/bit_floor_test.cpp
+++ b/test/bit_floor_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_bit_floor( T x )
 {
diff --git a/test/bit_popcount_test.cpp b/test/bit_popcount_test.cpp
index cf8ee870..7ecfa943 100644
--- a/test/bit_popcount_test.cpp
+++ b/test/bit_popcount_test.cpp
@@ -8,8 +8,8 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
-#include <iostream>
+#include <boost/config/std/limits.hpp>
+#include <boost/config/std/iostream.hpp>
 
 template<class T> void test_popcount( T x )
 {
diff --git a/test/bit_rotate_test.cpp b/test/bit_rotate_test.cpp
index d31c5e9f..19b94117 100644
--- a/test/bit_rotate_test.cpp
+++ b/test/bit_rotate_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 int const M = 256;
 
diff --git a/test/bit_rotate_test_cx.cpp b/test/bit_rotate_test_cx.cpp
index eff6f4bf..b2b741ae 100644
--- a/test/bit_rotate_test_cx.cpp
+++ b/test/bit_rotate_test_cx.cpp
@@ -14,7 +14,7 @@ BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined"
 #else
 
 #include <boost/core/bit.hpp>
-#include <cstdint>
+#include <boost/config/std/cstdint.hpp>
 
 #define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
 
diff --git a/test/bit_width_test.cpp b/test/bit_width_test.cpp
index 8f84ac57..11e7d666 100644
--- a/test/bit_width_test.cpp
+++ b/test/bit_width_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_width( T x )
 {
diff --git a/test/cmake_install_test/CMakeLists.txt b/test/cmake_install_test/CMakeLists.txt
index e2afe732..4e3a4b1c 100644
--- a/test/cmake_install_test/CMakeLists.txt
+++ b/test/cmake_install_test/CMakeLists.txt
@@ -2,7 +2,7 @@
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required(VERSION 3.5...3.16)
+cmake_minimum_required(VERSION 3.5...3.31)
 
 project(cmake_install_test LANGUAGES CXX)
 
diff --git a/test/cmake_subdir_test/CMakeLists.txt b/test/cmake_subdir_test/CMakeLists.txt
index 045a4765..5c0c84bc 100644
--- a/test/cmake_subdir_test/CMakeLists.txt
+++ b/test/cmake_subdir_test/CMakeLists.txt
@@ -2,7 +2,7 @@
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required(VERSION 3.5...3.16)
+cmake_minimum_required(VERSION 3.5...3.31)
 
 project(cmake_subdir_test LANGUAGES CXX)
 
diff --git a/test/cmath_test.cpp b/test/cmath_test.cpp
index 20b0aab2..a3a6c77d 100644
--- a/test/cmath_test.cpp
+++ b/test/cmath_test.cpp
@@ -4,12 +4,12 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#include <cfloat> // floating-point macros. Should appear before anything that might import std
 #include <boost/core/cmath.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/config.hpp>
 #include <boost/config/workaround.hpp>
-#include <limits>
-#include <cfloat>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_positive_normal( T x )
 {
diff --git a/test/data_test.cpp b/test/data_test.cpp
index 9849a9e3..26418cd4 100644
--- a/test/data_test.cpp
+++ b/test/data_test.cpp
@@ -9,7 +9,7 @@ Distributed under the Boost Software License, Version 1.0.
 #if !defined(BOOST_NO_CXX11_CONSTEXPR) && !defined(BOOST_NO_CXX11_DECLTYPE)
 #include <boost/core/data.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <iterator>
+#include <boost/config/std/iterator.hpp>
 
 class range {
 public:
diff --git a/test/default_allocator_test.cpp b/test/default_allocator_test.cpp
index 041c52ad..f3347f2e 100644
--- a/test/default_allocator_test.cpp
+++ b/test/default_allocator_test.cpp
@@ -7,8 +7,8 @@ Distributed under the Boost Software License, Version 1.0.
 */
 #include <boost/core/default_allocator.hpp>
 #include <boost/core/lightweight_test_trait.hpp>
-#include <vector>
-#include <list>
+#include <boost/config/std/vector.hpp>
+#include <boost/config/std/list.hpp>
 
 class type {
 public:
diff --git a/test/demangle_test.cpp b/test/demangle_test.cpp
index 0656ed55..f5f9a0f3 100644
--- a/test/demangle_test.cpp
+++ b/test/demangle_test.cpp
@@ -10,8 +10,8 @@
 //
 
 #include <boost/core/demangle.hpp>
-#include <typeinfo>
-#include <iostream>
+#include <boost/config/std/typeinfo.hpp>
+#include <boost/config/std/iostream.hpp>
 
 template<class T1, class T2> struct Y1
 {
diff --git a/test/demangled_name_test.cpp b/test/demangled_name_test.cpp
index fce32834..4c18283d 100644
--- a/test/demangled_name_test.cpp
+++ b/test/demangled_name_test.cpp
@@ -9,7 +9,7 @@
 //
 
 #include <boost/core/typeinfo.hpp>
-#include <iostream>
+#include <boost/config/std/iostream.hpp>
 
 template<class T1, class T2> struct Y1
 {
diff --git a/test/detail_iterator_test.cpp b/test/detail_iterator_test.cpp
index bafb4762..5c2fadd3 100644
--- a/test/detail_iterator_test.cpp
+++ b/test/detail_iterator_test.cpp
@@ -8,6 +8,17 @@
 // http://www.boost.org/LICENSE_1_0.txt
 //
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #define BOOST_ALLOW_DEPRECATED_HEADERS
 #include <boost/detail/iterator.hpp>
 #include <boost/core/lightweight_test_trait.hpp>
@@ -147,3 +158,5 @@ int main()
 
     return boost::report_errors();
 }
+
+#endif
diff --git a/test/eif_constructors.cpp b/test/eif_constructors.cpp
index 0cd3a974..1013150c 100644
--- a/test/eif_constructors.cpp
+++ b/test/eif_constructors.cpp
@@ -10,10 +10,21 @@
 //             Jeremiah Willcock (jewillco at osl.iu.edu)
 //             Andrew Lumsdaine (lums at osl.iu.edu)
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 using boost::enable_if;
 using boost::disable_if;
@@ -59,3 +70,5 @@ int main()
 
   return boost::report_errors();
 }
+
+#endif
diff --git a/test/eif_lazy.cpp b/test/eif_lazy.cpp
index fdb37e38..7fdbeaa7 100644
--- a/test/eif_lazy.cpp
+++ b/test/eif_lazy.cpp
@@ -10,6 +10,17 @@
 //             Jeremiah Willcock (jewillco at osl.iu.edu)
 //             Andrew Lumsdaine (lums at osl.iu.edu)
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.Utility/enable_if and Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits/is_same.hpp>
 #include <boost/core/lightweight_test.hpp>
@@ -79,3 +90,5 @@ int main()
   return boost::report_errors();
 }
 
+#endif
+
diff --git a/test/eif_member_templates.cpp b/test/eif_member_templates.cpp
index 54527337..3404ff3f 100644
--- a/test/eif_member_templates.cpp
+++ b/test/eif_member_templates.cpp
@@ -10,6 +10,17 @@
 //             Jeremiah Willcock (jewillco at osl.iu.edu)
 //             Andrew Lumsdaine (lums at osl.iu.edu)
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits/is_arithmetic.hpp>
 #include <boost/core/lightweight_test.hpp>
@@ -40,3 +51,5 @@ int main()
   return boost::report_errors();
 }
 
+#endif
+
diff --git a/test/eif_partial_specializations.cpp b/test/eif_partial_specializations.cpp
index 6940eca3..70ecf6a4 100644
--- a/test/eif_partial_specializations.cpp
+++ b/test/eif_partial_specializations.cpp
@@ -10,6 +10,17 @@
 //             Jeremiah Willcock (jewillco at osl.iu.edu)
 //             Andrew Lumsdaine (lums at osl.iu.edu)
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits/is_arithmetic.hpp>
 #include <boost/core/lightweight_test.hpp>
@@ -87,3 +98,5 @@ int main()
   return boost::report_errors();
 }
 
+#endif
+
diff --git a/test/fclose_deleter_test.cpp b/test/fclose_deleter_test.cpp
index 43633356..5a594423 100644
--- a/test/fclose_deleter_test.cpp
+++ b/test/fclose_deleter_test.cpp
@@ -12,6 +12,17 @@
  * This file contains tests for \c boost::fclose_deleter.
  */
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.SmartPtr and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/core/fclose_deleter.hpp>
 #include <cstdio>
 #include <cstddef>
@@ -71,3 +82,5 @@ int main()
 
     std::remove(filename);
 }
+
+#endif
diff --git a/test/functor_test.cpp b/test/functor_test.cpp
index 873e5b0a..4e12ac03 100644
--- a/test/functor_test.cpp
+++ b/test/functor_test.cpp
@@ -19,7 +19,7 @@
 #include <boost/core/functor.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/lightweight_test_trait.hpp>
-#include <type_traits>
+#include <boost/config/std/type_traits.hpp>
 
 #if (defined(__cpp_lib_is_invocable) && (__cpp_lib_is_invocable >= 201703l)) || \
     (defined(BOOST_MSSTL_VERSION) && (BOOST_MSSTL_VERSION >= 140) && (BOOST_CXX_VERSION >= 201703l))
diff --git a/test/get_pointer_test.cpp b/test/get_pointer_test.cpp
index 4bccccb6..a057e998 100644
--- a/test/get_pointer_test.cpp
+++ b/test/get_pointer_test.cpp
@@ -14,7 +14,7 @@
 
 #include <boost/get_pointer.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <memory>
+#include <boost/config/std/memory.hpp>
 
 struct X
 {
diff --git a/test/has_single_bit_test.cpp b/test/has_single_bit_test.cpp
index 221f8c7b..1b7c01b0 100644
--- a/test/has_single_bit_test.cpp
+++ b/test/has_single_bit_test.cpp
@@ -8,7 +8,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/cstdint.hpp>
-#include <limits>
+#include <boost/config/std/limits.hpp>
 
 template<class T> void test_single_bit( T x )
 {
diff --git a/test/identity_rvalue_test.cpp b/test/identity_rvalue_test.cpp
index 5cd4e9b8..7afd2057 100644
--- a/test/identity_rvalue_test.cpp
+++ b/test/identity_rvalue_test.cpp
@@ -9,10 +9,10 @@ Distributed under the Boost Software License, Version 1.0.
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 #include <boost/core/identity.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <algorithm>
-#include <iterator>
-#include <string>
-#include <vector>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/iterator.hpp>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/vector.hpp>
 
 bool test(std::string&&)
 {
diff --git a/test/identity_test.cpp b/test/identity_test.cpp
index e82e450b..2278c8ba 100644
--- a/test/identity_test.cpp
+++ b/test/identity_test.cpp
@@ -7,10 +7,10 @@ Distributed under the Boost Software License, Version 1.0.
 */
 #include <boost/core/identity.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <algorithm>
-#include <iterator>
-#include <string>
-#include <vector>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/iterator.hpp>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/vector.hpp>
 
 bool test(std::string&)
 {
diff --git a/test/ignore_unused_test.cpp b/test/ignore_unused_test.cpp
index 67bdd800..bd019734 100644
--- a/test/ignore_unused_test.cpp
+++ b/test/ignore_unused_test.cpp
@@ -5,6 +5,7 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #include <boost/core/ignore_unused.hpp>
+#include <boost/config.hpp>
 
 BOOST_CXX14_CONSTEXPR int test_fun(int a)
 {
diff --git a/test/launder_test.cpp b/test/launder_test.cpp
index 98adcfb4..af349975 100644
--- a/test/launder_test.cpp
+++ b/test/launder_test.cpp
@@ -4,7 +4,7 @@
 
 #include <boost/core/launder.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <new>
+#include <boost/config/std/new.hpp>
 
 struct X
 {
diff --git a/test/lightweight_test_all_eq_test.cpp b/test/lightweight_test_all_eq_test.cpp
index 46254e75..df586bb9 100644
--- a/test/lightweight_test_all_eq_test.cpp
+++ b/test/lightweight_test_all_eq_test.cpp
@@ -8,8 +8,8 @@
 // http://www.boost.org/LICENSE_1_0.txt
 //
 
-#include <vector>
-#include <set>
+#include <boost/config/std/vector.hpp>
+#include <boost/config/std/set.hpp>
 #include <boost/core/lightweight_test.hpp>
 
 int main()
diff --git a/test/lightweight_test_all_with_fail.cpp b/test/lightweight_test_all_with_fail.cpp
index 9a4a4293..d81d3964 100644
--- a/test/lightweight_test_all_with_fail.cpp
+++ b/test/lightweight_test_all_with_fail.cpp
@@ -8,9 +8,9 @@
 // http://www.boost.org/LICENSE_1_0.txt
 //
 
-#include <cmath>
-#include <functional>
-#include <vector>
+#include <boost/config/std/cmath.hpp>
+#include <boost/config/std/functional.hpp>
+#include <boost/config/std/vector.hpp>
 #include <boost/core/lightweight_test.hpp>
 
 int fail_vector()
diff --git a/test/lightweight_test_all_with_test.cpp b/test/lightweight_test_all_with_test.cpp
index bc078a41..d976242f 100644
--- a/test/lightweight_test_all_with_test.cpp
+++ b/test/lightweight_test_all_with_test.cpp
@@ -8,9 +8,9 @@
 // http://www.boost.org/LICENSE_1_0.txt
 //
 
-#include <cmath>
-#include <functional>
-#include <vector>
+#include <boost/config/std/cmath.hpp>
+#include <boost/config/std/functional.hpp>
+#include <boost/config/std/vector.hpp>
 #include <boost/core/lightweight_test.hpp>
 
 void test_vector()
diff --git a/test/lightweight_test_bool.cpp b/test/lightweight_test_bool.cpp
index bb178711..d35e9e89 100644
--- a/test/lightweight_test_bool.cpp
+++ b/test/lightweight_test_bool.cpp
@@ -3,7 +3,7 @@
 // https://www.boost.org/LICENSE_1_0.txt
 
 #include <boost/core/lightweight_test.hpp>
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 int main()
 {
diff --git a/test/lightweight_test_test.cpp b/test/lightweight_test_test.cpp
index 7460af9a..c3a77c16 100644
--- a/test/lightweight_test_test.cpp
+++ b/test/lightweight_test_test.cpp
@@ -15,7 +15,7 @@
 #endif
 
 #include <boost/core/lightweight_test.hpp>
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 struct X
 {
diff --git a/test/lightweight_test_test3.cpp b/test/lightweight_test_test3.cpp
index cda641aa..e3da6a76 100644
--- a/test/lightweight_test_test3.cpp
+++ b/test/lightweight_test_test3.cpp
@@ -10,7 +10,7 @@
 
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/noncopyable.hpp>
-#include <ostream>
+#include <boost/config/std/ostream.hpp>
 
 // EQ
 
diff --git a/test/lightweight_test_with_fail.cpp b/test/lightweight_test_with_fail.cpp
index 4583c2cc..cd952603 100644
--- a/test/lightweight_test_with_fail.cpp
+++ b/test/lightweight_test_with_fail.cpp
@@ -7,7 +7,7 @@
 // https://www.boost.org/LICENSE_1_0.txt
 
 #include <boost/core/lightweight_test.hpp>
-#include <cmath>
+#include <boost/config/std/cmath.hpp>
 
 template <typename T>
 struct with_tolerance
diff --git a/test/lightweight_test_with_test.cpp b/test/lightweight_test_with_test.cpp
index 461d1e63..ecc06615 100644
--- a/test/lightweight_test_with_test.cpp
+++ b/test/lightweight_test_with_test.cpp
@@ -9,7 +9,7 @@
 //
 
 #include <boost/core/lightweight_test.hpp>
-#include <cmath>
+#include <boost/config/std/cmath.hpp>
 
 template <typename T>
 struct with_tolerance
diff --git a/test/max_align_test.cpp b/test/max_align_test.cpp
index 45b8e35f..d66bf452 100644
--- a/test/max_align_test.cpp
+++ b/test/max_align_test.cpp
@@ -2,11 +2,22 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.TypeTraits and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/core/max_align.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/type_traits.hpp>
 #include <boost/config.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 #if defined(BOOST_LIBSTDCXX_VERSION) && BOOST_LIBSTDCXX_VERSION < 40900
 # define BOOST_NO_STD_MAX_ALIGN_T
@@ -61,3 +72,5 @@ int main()
 
     return boost::report_errors();
 }
+
+#endif
diff --git a/test/memory_resource_test.cpp b/test/memory_resource_test.cpp
index a95d558e..40aad1b2 100644
--- a/test/memory_resource_test.cpp
+++ b/test/memory_resource_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/memory_resource.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <new>
-#include <cstddef>
+#include <boost/config/std/new.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 static bool do_allocate_called;
 static std::size_t do_allocate_bytes;
diff --git a/test/no_exceptions_support_test.cpp b/test/no_exceptions_support_test.cpp
index 6cce8ae2..3c83d796 100644
--- a/test/no_exceptions_support_test.cpp
+++ b/test/no_exceptions_support_test.cpp
@@ -17,7 +17,7 @@
 #include <boost/core/no_exceptions_support.hpp>
 #include <boost/core/quick_exit.hpp>
 #include <boost/throw_exception.hpp>
-#include <exception>
+#include <boost/config/std/exception.hpp>
 
 void f()
 {
diff --git a/test/noinit_adaptor_test.cpp b/test/noinit_adaptor_test.cpp
index 605941f0..e3a27132 100644
--- a/test/noinit_adaptor_test.cpp
+++ b/test/noinit_adaptor_test.cpp
@@ -8,7 +8,7 @@ Distributed under the Boost Software License, Version 1.0.
 #include <boost/core/noinit_adaptor.hpp>
 #include <boost/core/default_allocator.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 template<class T>
 class creator
diff --git a/test/noncopyable_compile_fail.cpp b/test/noncopyable_compile_fail.cpp
index f1f02938..0619acf0 100644
--- a/test/noncopyable_compile_fail.cpp
+++ b/test/noncopyable_compile_fail.cpp
@@ -11,7 +11,7 @@
 //   2 Jun 99  Initial Version
 
 #include <boost/noncopyable.hpp>
-#include <iostream>
+#include <boost/config/std/iostream.hpp>
 
 //  This program demonstrates compiler errors resulting from trying to copy
 //  construct or copy assign a class object derived from class noncopyable.
diff --git a/test/serialization_construct_data_test.cpp b/test/serialization_construct_data_test.cpp
index ee87e616..0c09ad46 100644
--- a/test/serialization_construct_data_test.cpp
+++ b/test/serialization_construct_data_test.cpp
@@ -9,7 +9,7 @@
 #endif
 
 #include <boost/core/serialization.hpp>
-#include <new>
+#include <boost/config/std/new.hpp>
 
 struct X
 {
@@ -71,8 +71,8 @@ struct Y
 #include <boost/archive/text_oarchive.hpp>
 #include <boost/archive/text_iarchive.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <sstream>
-#include <string>
+#include <boost/config/std/sstream.hpp>
+#include <boost/config/std/string.hpp>
 
 int main()
 {
diff --git a/test/serialization_nvp_test.cpp b/test/serialization_nvp_test.cpp
index 588c9a55..b7952bb0 100644
--- a/test/serialization_nvp_test.cpp
+++ b/test/serialization_nvp_test.cpp
@@ -24,8 +24,8 @@ struct X
 #include <boost/archive/xml_oarchive.hpp>
 #include <boost/archive/xml_iarchive.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <sstream>
-#include <string>
+#include <boost/config/std/sstream.hpp>
+#include <boost/config/std/string.hpp>
 
 int main()
 {
diff --git a/test/serialization_split_free_test.cpp b/test/serialization_split_free_test.cpp
index 9c92ae92..af6251db 100644
--- a/test/serialization_split_free_test.cpp
+++ b/test/serialization_split_free_test.cpp
@@ -35,8 +35,8 @@ template<class Ar> void serialize( Ar& ar, X& x, unsigned v )
 #include <boost/archive/text_oarchive.hpp>
 #include <boost/archive/text_iarchive.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <sstream>
-#include <string>
+#include <boost/config/std/sstream.hpp>
+#include <boost/config/std/string.hpp>
 
 int main()
 {
diff --git a/test/serialization_split_member_test.cpp b/test/serialization_split_member_test.cpp
index 9c1a8b26..7dcc5976 100644
--- a/test/serialization_split_member_test.cpp
+++ b/test/serialization_split_member_test.cpp
@@ -39,8 +39,8 @@ struct X
 #include <boost/archive/text_oarchive.hpp>
 #include <boost/archive/text_iarchive.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <sstream>
-#include <string>
+#include <boost/config/std/sstream.hpp>
+#include <boost/config/std/string.hpp>
 
 int main()
 {
diff --git a/test/size_test.cpp b/test/size_test.cpp
index 905ca8d5..7053b702 100644
--- a/test/size_test.cpp
+++ b/test/size_test.cpp
@@ -9,7 +9,7 @@ Distributed under the Boost Software License, Version 1.0.
 #if !defined(BOOST_NO_CXX11_CONSTEXPR) && !defined(BOOST_NO_CXX11_DECLTYPE)
 #include <boost/core/size.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <iterator>
+#include <boost/config/std/iterator.hpp>
 
 struct range {
     std::size_t size() const {
diff --git a/test/snprintf_test.cpp b/test/snprintf_test.cpp
index 48483ba2..1ea865d0 100644
--- a/test/snprintf_test.cpp
+++ b/test/snprintf_test.cpp
@@ -13,8 +13,8 @@
  */
 
 #include <boost/core/snprintf.hpp>
-#include <cstddef>
-#include <cstring>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/config/std/cstring.hpp>
 #include <boost/core/lightweight_test.hpp>
 
 void test_snprintf()
diff --git a/test/sp_typeinfo_test.cpp b/test/sp_typeinfo_test.cpp
index 95557f6b..5bd547c6 100644
--- a/test/sp_typeinfo_test.cpp
+++ b/test/sp_typeinfo_test.cpp
@@ -12,7 +12,7 @@
 
 #include <boost/detail/sp_typeinfo.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <iostream>
+#include <boost/config/std/iostream.hpp>
 
 int main()
 {
diff --git a/test/span_boost_begin_test.cpp b/test/span_boost_begin_test.cpp
index b7dc1e63..a8c359af 100644
--- a/test/span_boost_begin_test.cpp
+++ b/test/span_boost_begin_test.cpp
@@ -8,7 +8,7 @@ Distributed under the Boost Software License, Version 1.0.
 #include <boost/config.hpp>
 #if !defined(BOOST_NO_CXX11_CONSTEXPR) && !defined(BOOST_NO_CXX11_DECLTYPE)
 #include <boost/core/span.hpp>
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 namespace boost {
 namespace begin_ {
diff --git a/test/span_nonmem_data_size_test.cpp b/test/span_nonmem_data_size_test.cpp
index cc0b2316..e4f0bf65 100644
--- a/test/span_nonmem_data_size_test.cpp
+++ b/test/span_nonmem_data_size_test.cpp
@@ -19,7 +19,7 @@
 #if !defined(BOOST_NO_CXX11_CONSTEXPR) && !defined(BOOST_NO_CXX11_DECLTYPE)
 
 #include <boost/core/span.hpp>
-#include <iterator>
+#include <boost/config/std/iterator.hpp>
 
 // Note: This preprocessor check should be equivalent to those in boost/core/data.hpp and boost/core/size.hpp
 #if (defined(__cpp_lib_nonmember_container_access) && (__cpp_lib_nonmember_container_access >= 201411l)) || \
diff --git a/test/sv_common_reference_test.cpp b/test/sv_common_reference_test.cpp
index 3a0b4444..0738dced 100644
--- a/test/sv_common_reference_test.cpp
+++ b/test/sv_common_reference_test.cpp
@@ -6,7 +6,7 @@
 #include <boost/core/lightweight_test_trait.hpp>
 #include <boost/config/pragma_message.hpp>
 #include <boost/config.hpp>
-#include <string>
+#include <boost/config/std/string.hpp>
 
 #if defined(BOOST_NO_CXX20_HDR_CONCEPTS)
 
@@ -15,8 +15,8 @@ int main() {}
 
 #else
 
-#include <concepts>
-#include <type_traits>
+#include <boost/config/std/concepts.hpp>
+#include <boost/config/std/type_traits.hpp>
 
 using T = std::common_reference_t< boost::core::string_view&&, std::string& >;
 
diff --git a/test/sv_common_reference_test2.cpp b/test/sv_common_reference_test2.cpp
index 91e61e09..adb4cd64 100644
--- a/test/sv_common_reference_test2.cpp
+++ b/test/sv_common_reference_test2.cpp
@@ -4,8 +4,9 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/config/pragma_message.hpp>
-#include <string>
-#include <iterator>
+#include <boost/config.hpp>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/iterator.hpp>
 
 #if !defined(__cpp_lib_ranges)
 
diff --git a/test/sv_compare_test.cpp b/test/sv_compare_test.cpp
index eef12d61..f5632630 100644
--- a/test/sv_compare_test.cpp
+++ b/test/sv_compare_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <stdexcept>
-#include <cstddef>
+#include <boost/config/std/stdexcept.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_construct_test.cpp b/test/sv_construct_test.cpp
index 3da015b2..a55ed0e2 100644
--- a/test/sv_construct_test.cpp
+++ b/test/sv_construct_test.cpp
@@ -16,13 +16,13 @@
 # endif
 #endif
 
-#include <iterator>
-#include <string>
+#include <boost/config/std/iterator.hpp>
+#include <boost/config/std/string.hpp>
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 #if !defined(BOOST_NO_CXX17_HDR_MEMORY_RESOURCE)
-# include <memory_resource>
+# include <boost/config/std/memory_resource.hpp>
 #endif
 
 template<class It> std::reverse_iterator<It> make_reverse_iterator( It it )
diff --git a/test/sv_construct_test_cx.cpp b/test/sv_construct_test_cx.cpp
index f490d16e..f5440cab 100644
--- a/test/sv_construct_test_cx.cpp
+++ b/test/sv_construct_test_cx.cpp
@@ -14,7 +14,7 @@ int main() {}
 #else
 
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 
 #define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
diff --git a/test/sv_contains_test.cpp b/test/sv_contains_test.cpp
index f42f1e42..4378aef7 100644
--- a/test/sv_contains_test.cpp
+++ b/test/sv_contains_test.cpp
@@ -4,7 +4,7 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_conversion_test.cpp b/test/sv_conversion_test.cpp
index f9cec64e..a1d44db8 100644
--- a/test/sv_conversion_test.cpp
+++ b/test/sv_conversion_test.cpp
@@ -16,12 +16,12 @@
 # endif
 #endif
 
-#include <string>
+#include <boost/config/std/string.hpp>
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 #if !defined(BOOST_NO_CXX17_HDR_MEMORY_RESOURCE)
-# include <memory_resource>
+# include <boost/config/std/memory_resource.hpp>
 #endif
 
 boost::core::string_view f( boost::core::string_view const& str )
diff --git a/test/sv_conversion_test2.cpp b/test/sv_conversion_test2.cpp
index ee0e196c..e882ce55 100644
--- a/test/sv_conversion_test2.cpp
+++ b/test/sv_conversion_test2.cpp
@@ -2,10 +2,21 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.Utility (string_view) and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/core/detail/string_view.hpp>
 #include <boost/utility/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <string>
+#include <boost/config/std/string.hpp>
 
 boost::core::string_view f( boost::core::string_view const& str )
 {
@@ -30,3 +41,5 @@ int main()
 
     return boost::report_errors();
 }
+
+#endif
diff --git a/test/sv_copy_test.cpp b/test/sv_copy_test.cpp
index 75abe882..9df1df3c 100644
--- a/test/sv_copy_test.cpp
+++ b/test/sv_copy_test.cpp
@@ -6,8 +6,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <stdexcept>
-#include <cstddef>
+#include <boost/config/std/stdexcept.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_element_access_test.cpp b/test/sv_element_access_test.cpp
index e4a94f73..6f337270 100644
--- a/test/sv_element_access_test.cpp
+++ b/test/sv_element_access_test.cpp
@@ -4,7 +4,7 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <stdexcept>
+#include <boost/config/std/stdexcept.hpp>
 
 int main()
 {
diff --git a/test/sv_ends_with_test.cpp b/test/sv_ends_with_test.cpp
index 86de3daf..94359e0d 100644
--- a/test/sv_ends_with_test.cpp
+++ b/test/sv_ends_with_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <stdexcept>
-#include <cstddef>
+#include <boost/config/std/stdexcept.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_eq_test.cpp b/test/sv_eq_test.cpp
index a6d3e29e..d33bd7da 100644
--- a/test/sv_eq_test.cpp
+++ b/test/sv_eq_test.cpp
@@ -16,12 +16,12 @@
 # endif
 #endif
 
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 #if !defined(BOOST_NO_CXX17_HDR_MEMORY_RESOURCE)
-# include <memory_resource>
+# include <boost/config/std/memory_resource.hpp>
 #endif
 
 #define TEST_EQ(x, y) \
diff --git a/test/sv_find_first_not_of_test.cpp b/test/sv_find_first_not_of_test.cpp
index c94c5be9..6988f021 100644
--- a/test/sv_find_first_not_of_test.cpp
+++ b/test/sv_find_first_not_of_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <algorithm>
-#include <cstddef>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_find_first_of_test.cpp b/test/sv_find_first_of_test.cpp
index 59a255f9..326e9d79 100644
--- a/test/sv_find_first_of_test.cpp
+++ b/test/sv_find_first_of_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <algorithm>
-#include <cstddef>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_find_last_not_of_test.cpp b/test/sv_find_last_not_of_test.cpp
index 6bdd0175..a7bb036c 100644
--- a/test/sv_find_last_not_of_test.cpp
+++ b/test/sv_find_last_not_of_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <algorithm>
-#include <cstddef>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_find_last_of_test.cpp b/test/sv_find_last_of_test.cpp
index 62482240..f1399ce4 100644
--- a/test/sv_find_last_of_test.cpp
+++ b/test/sv_find_last_of_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <algorithm>
-#include <cstddef>
+#include <boost/config/std/algorithm.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_find_test.cpp b/test/sv_find_test.cpp
index cdf97ac0..512a5c34 100644
--- a/test/sv_find_test.cpp
+++ b/test/sv_find_test.cpp
@@ -4,7 +4,7 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_format_test.cpp b/test/sv_format_test.cpp
index dc2c045e..4575abd6 100644
--- a/test/sv_format_test.cpp
+++ b/test/sv_format_test.cpp
@@ -14,8 +14,8 @@ int main() {}
 
 #else
 
-#include <format>
-#include <string_view>
+#include <boost/config/std/format.hpp>
+#include <boost/config/std/string_view.hpp>
 
 int main()
 {
diff --git a/test/sv_hash_test.cpp b/test/sv_hash_test.cpp
index ce05f21b..9b47f183 100644
--- a/test/sv_hash_test.cpp
+++ b/test/sv_hash_test.cpp
@@ -2,11 +2,22 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
+#ifdef BOOST_USE_MODULES
+
+import std.compat;
+
+int main()
+{
+    printf("This test depends on Boost.ContainerHash and can't be run with C++20 modules yet\n");
+}
+
+#else
+
 #include <boost/core/detail/string_view.hpp>
 #include <boost/container_hash/hash.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/config.hpp>
-#include <string>
+#include <boost/config/std/string.hpp>
 
 template<class T> std::size_t hv( T const& t )
 {
@@ -46,3 +57,5 @@ int main()
 
     return boost::report_errors();
 }
+
+#endif
diff --git a/test/sv_iteration_test.cpp b/test/sv_iteration_test.cpp
index 57078d64..341d59e1 100644
--- a/test/sv_iteration_test.cpp
+++ b/test/sv_iteration_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <string>
-#include <algorithm>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/algorithm.hpp>
 
 int main()
 {
diff --git a/test/sv_lt_test.cpp b/test/sv_lt_test.cpp
index 4661afd1..593d5e5c 100644
--- a/test/sv_lt_test.cpp
+++ b/test/sv_lt_test.cpp
@@ -16,12 +16,12 @@
 # endif
 #endif
 
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 #if !defined(BOOST_NO_CXX17_HDR_MEMORY_RESOURCE)
-# include <memory_resource>
+# include <boost/config/std/memory_resource.hpp>
 #endif
 
 #define TEST_LT(x, y) \
diff --git a/test/sv_modifiers_test.cpp b/test/sv_modifiers_test.cpp
index 1a4d2b08..a88c6330 100644
--- a/test/sv_modifiers_test.cpp
+++ b/test/sv_modifiers_test.cpp
@@ -4,7 +4,7 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_rfind_test.cpp b/test/sv_rfind_test.cpp
index 12ab0cc6..768db7a3 100644
--- a/test/sv_rfind_test.cpp
+++ b/test/sv_rfind_test.cpp
@@ -4,7 +4,7 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <cstddef>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_starts_with_test.cpp b/test/sv_starts_with_test.cpp
index 8fa88692..93d7d4c3 100644
--- a/test/sv_starts_with_test.cpp
+++ b/test/sv_starts_with_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <stdexcept>
-#include <cstddef>
+#include <boost/config/std/stdexcept.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_stream_insert_test.cpp b/test/sv_stream_insert_test.cpp
index 864c2bd8..75a02da6 100644
--- a/test/sv_stream_insert_test.cpp
+++ b/test/sv_stream_insert_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <sstream>
-#include <iomanip>
+#include <boost/config/std/sstream.hpp>
+#include <boost/config/std/iomanip.hpp>
 
 int main()
 {
diff --git a/test/sv_substr_test.cpp b/test/sv_substr_test.cpp
index 51cde0ab..fe416818 100644
--- a/test/sv_substr_test.cpp
+++ b/test/sv_substr_test.cpp
@@ -4,8 +4,8 @@
 
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <stdexcept>
-#include <cstddef>
+#include <boost/config/std/stdexcept.hpp>
+#include <boost/config/std/cstddef.hpp>
 
 int main()
 {
diff --git a/test/sv_types_test.cpp b/test/sv_types_test.cpp
index d0725661..39e73d34 100644
--- a/test/sv_types_test.cpp
+++ b/test/sv_types_test.cpp
@@ -5,7 +5,7 @@
 #include <boost/core/detail/string_view.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/lightweight_test_trait.hpp>
-#include <iterator>
+#include <boost/config/std/iterator.hpp>
 
 #if defined(_LIBCPP_VERSION) && _LIBCPP_VERSION >= 160000
 
diff --git a/test/swap/swap_array_of_array_of_class.cpp b/test/swap/swap_array_of_array_of_class.cpp
index 5f0a7e6c..50ac5d33 100644
--- a/test/swap/swap_array_of_array_of_class.cpp
+++ b/test/swap/swap_array_of_array_of_class.cpp
@@ -14,8 +14,8 @@
 //Put test class in the global namespace
 #include "./swap_test_class.hpp"
 
-#include <algorithm> //for std::copy and std::equal
-#include <cstddef> //for std::size_t
+#include <boost/config/std/algorithm.hpp>  //for std::copy and std::equal
+#include <boost/config/std/cstddef.hpp> //for std::size_t
 
 #if defined(__clang__)
 # pragma clang diagnostic ignored "-Wunused-function"
diff --git a/test/swap/swap_array_of_array_of_int.cpp b/test/swap/swap_array_of_array_of_int.cpp
index 8fe45f96..15e9a5a2 100644
--- a/test/swap/swap_array_of_array_of_int.cpp
+++ b/test/swap/swap_array_of_array_of_int.cpp
@@ -11,8 +11,8 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <algorithm> //for std::copy and std::equal
-#include <cstddef> //for std::size_t
+#include <boost/config/std/algorithm.hpp> //for std::copy and std::equal
+#include <boost/config/std/cstddef.hpp> //for std::size_t
 
 int main()
 {
diff --git a/test/swap/swap_array_of_class.cpp b/test/swap/swap_array_of_class.cpp
index 52c529de..e0ab3c45 100644
--- a/test/swap/swap_array_of_class.cpp
+++ b/test/swap/swap_array_of_class.cpp
@@ -14,8 +14,8 @@
 //Put test class in the global namespace
 #include "./swap_test_class.hpp"
 
-#include <algorithm> //for std::copy and std::equal
-#include <cstddef> //for std::size_t
+#include <boost/config/std/algorithm.hpp> //for std::copy and std::equal
+#include <boost/config/std/cstddef.hpp> //for std::size_t
 
 #if defined(__clang__)
 # pragma clang diagnostic ignored "-Wunused-function"
diff --git a/test/swap/swap_array_of_int.cpp b/test/swap/swap_array_of_int.cpp
index 9f4775eb..f5045530 100644
--- a/test/swap/swap_array_of_int.cpp
+++ b/test/swap/swap_array_of_int.cpp
@@ -11,8 +11,8 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <algorithm> //for std::copy and std::equal
-#include <cstddef> //for std::size_t
+#include <boost/config/std/algorithm.hpp> //for std::copy and std::equal
+#include <boost/config/std/cstddef.hpp> //for std::size_t
 
 
 int main()
diff --git a/test/swap/swap_array_of_template.cpp b/test/swap/swap_array_of_template.cpp
index 3921eabe..f679dd58 100644
--- a/test/swap/swap_array_of_template.cpp
+++ b/test/swap/swap_array_of_template.cpp
@@ -14,8 +14,8 @@
 //Put test class in the global namespace
 #include "./swap_test_class.hpp"
 
-#include <algorithm> //for std::copy and std::equal
-#include <cstddef> //for std::size_t
+#include <boost/config/std/algorithm.hpp> //for std::copy and std::equal
+#include <boost/config/std/cstddef.hpp> //for std::size_t
 
 template <class T>
 class swap_test_template
diff --git a/test/swap/swap_std_bitset.cpp b/test/swap/swap_std_bitset.cpp
index 7b8e5d19..f74dbb6b 100644
--- a/test/swap/swap_std_bitset.cpp
+++ b/test/swap/swap_std_bitset.cpp
@@ -13,7 +13,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <bitset>
+#include <boost/config/std/bitset.hpp>
 
 int main()
 {
diff --git a/test/swap/swap_std_dateorder.cpp b/test/swap/swap_std_dateorder.cpp
index d26729d2..177e64c4 100644
--- a/test/swap/swap_std_dateorder.cpp
+++ b/test/swap/swap_std_dateorder.cpp
@@ -13,7 +13,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <locale>
+#include <boost/config/std/locale.hpp>
 
 int main()
 {
diff --git a/test/swap/swap_std_string.cpp b/test/swap/swap_std_string.cpp
index 14c8e7c2..6978b80b 100644
--- a/test/swap/swap_std_string.cpp
+++ b/test/swap/swap_std_string.cpp
@@ -12,7 +12,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <string>
+#include <boost/config/std/string.hpp>
 
 int main()
 {
diff --git a/test/swap/swap_std_typeinfo_ptr.cpp b/test/swap/swap_std_typeinfo_ptr.cpp
index b255aa72..c3fb8d25 100644
--- a/test/swap/swap_std_typeinfo_ptr.cpp
+++ b/test/swap/swap_std_typeinfo_ptr.cpp
@@ -13,7 +13,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <typeinfo>
+#include <boost/config/std/typeinfo.hpp>
 
 int main()
 {
diff --git a/test/swap/swap_std_vector_of_boost.cpp b/test/swap/swap_std_vector_of_boost.cpp
index f32a168a..3272385d 100644
--- a/test/swap/swap_std_vector_of_boost.cpp
+++ b/test/swap/swap_std_vector_of_boost.cpp
@@ -12,7 +12,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 //Put test class in namespace boost
 namespace boost
diff --git a/test/swap/swap_std_vector_of_global.cpp b/test/swap/swap_std_vector_of_global.cpp
index f394b1ac..529a22c7 100644
--- a/test/swap/swap_std_vector_of_global.cpp
+++ b/test/swap/swap_std_vector_of_global.cpp
@@ -12,7 +12,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 //Put test class in the global namespace
 #include "./swap_test_class.hpp"
diff --git a/test/swap/swap_std_vector_of_other.cpp b/test/swap/swap_std_vector_of_other.cpp
index d7d43964..0f778aa9 100644
--- a/test/swap/swap_std_vector_of_other.cpp
+++ b/test/swap/swap_std_vector_of_other.cpp
@@ -12,7 +12,7 @@
 #define BOOST_CHECK BOOST_TEST
 #define BOOST_CHECK_EQUAL BOOST_TEST_EQ
 
-#include <vector>
+#include <boost/config/std/vector.hpp>
 
 //Put test class in namespace other
 namespace other
diff --git a/test/type_name_test.cpp b/test/type_name_test.cpp
index 08cc8727..f73e10da 100644
--- a/test/type_name_test.cpp
+++ b/test/type_name_test.cpp
@@ -5,34 +5,34 @@
 #include <boost/core/type_name.hpp>
 #include <boost/core/lightweight_test.hpp>
 #include <boost/config.hpp>
-#include <string>
-#include <vector>
-#include <list>
-#include <deque>
-#include <set>
-#include <map>
-#include <utility>
-#include <cstddef>
-#include <iosfwd>
+#include <boost/config/std/string.hpp>
+#include <boost/config/std/vector.hpp>
+#include <boost/config/std/list.hpp>
+#include <boost/config/std/deque.hpp>
+#include <boost/config/std/set.hpp>
+#include <boost/config/std/map.hpp>
+#include <boost/config/std/utility.hpp>
+#include <boost/config/std/cstddef.hpp>
+#include <boost/config/std/iosfwd.hpp>
 
 #if !defined(BOOST_NO_CXX11_HDR_UNORDERED_SET)
-# include <unordered_set>
+# include <boost/config/std/unordered_set.hpp>
 #endif
 
 #if !defined(BOOST_NO_CXX11_HDR_UNORDERED_MAP)
-# include <unordered_map>
+# include <boost/config/std/unordered_map.hpp>
 #endif
 
 #if !defined(BOOST_NO_CXX11_HDR_ARRAY)
-# include <array>
+# include <boost/config/std/array.hpp>
 #endif
 
 #if !defined(BOOST_NO_CXX11_HDR_TUPLE)
-# include <tuple>
+# include <boost/config/std/tuple.hpp>
 #endif
 
 #if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
-# include <string_view>
+# include <boost/config/std/string_view.hpp>
 #endif
 
 //
diff --git a/test/typeinfo_test.cpp b/test/typeinfo_test.cpp
index 3e122bb1..a5214213 100644
--- a/test/typeinfo_test.cpp
+++ b/test/typeinfo_test.cpp
@@ -10,7 +10,7 @@
 
 #include <boost/core/typeinfo.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <iostream>
+#include <boost/config/std/iostream.hpp>
 
 int main()
 {
diff --git a/test/verbose_terminate_handler_fail.cpp b/test/verbose_terminate_handler_fail.cpp
index 31c6bc40..7b5b0fe1 100644
--- a/test/verbose_terminate_handler_fail.cpp
+++ b/test/verbose_terminate_handler_fail.cpp
@@ -10,7 +10,7 @@
 
 #include <boost/core/verbose_terminate_handler.hpp>
 #include <boost/throw_exception.hpp>
-#include <exception>
+#include <boost/config/std/exception.hpp>
 #include <stdlib.h>
 #if defined(_MSC_VER) && defined(_CPPLIB_VER) && defined(_DEBUG)
 # include <crtdbg.h>
diff --git a/test/visit_each_test.cpp b/test/visit_each_test.cpp
index d1fcc3cd..b8a1ce8c 100644
--- a/test/visit_each_test.cpp
+++ b/test/visit_each_test.cpp
@@ -10,7 +10,7 @@
 
 #include <boost/visit_each.hpp>
 #include <boost/core/lightweight_test.hpp>
-#include <string>
+#include <boost/config/std/string.hpp>
 
 struct X
 {
diff --git a/tools/install-cmake.sh b/tools/install-cmake.sh
new file mode 100755
index 00000000..d2fd0bba
--- /dev/null
+++ b/tools/install-cmake.sh
@@ -0,0 +1,15 @@
+#!/bin/bash
+#
+# Copyright (c) 2026 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
+
+set -e
+
+wget https://github.com/Kitware/CMake/releases/download/v4.2.3/cmake-4.2.3-linux-x86_64.tar.gz
+tar -xf cmake-4.2.3-linux-x86_64.tar.gz
+mv cmake-4.2.3-linux-x86_64 /opt/cmake
+update-alternatives --install /usr/bin/cmake cmake /opt/cmake/bin/cmake 100
+update-alternatives --install /usr/bin/ctest ctest /opt/cmake/bin/ctest 100
diff --git a/tools/setup_boost_with_modules.py b/tools/setup_boost_with_modules.py
new file mode 100644
index 00000000..4d2ee48b
--- /dev/null
+++ b/tools/setup_boost_with_modules.py
@@ -0,0 +1,28 @@
+#!/usr/bin/python
+
+# This is a temporary workaround to make CIs use the
+# "Boost with C++20 modules" proposal, instead of the regular develop branch
+# Call it instead of depinst
+
+from subprocess import check_call
+import os
+
+def main():
+
+    submodules = [
+        ('tools/cmake',         'https://github.com/anarthal/boost-cmake'),
+        ('libs/assert',         'https://github.com/anarthal/assert'),
+        ('libs/throw_exception','https://github.com/anarthal/throw_exception'),
+        ('libs/config',         'https://github.com/anarthal/config'),
+    ]
+
+    for submodule, url in submodules:
+        os.chdir(submodule)
+        check_call(['git', 'remote', 'add', 'modules', url])
+        check_call(['git', 'fetch', '--depth', '1', 'modules', 'feature/cxx20-modules'])
+        check_call(['git', 'checkout', 'modules/feature/cxx20-modules'])
+        os.chdir('../..')
+
+
+if __name__ == '__main__':
+    main()