diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b20576c..47d4c37 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,4 +1,4 @@
-name: GitHub Actions CI
+name: CI
 
 on:
   pull_request:
@@ -18,47 +18,202 @@ jobs:
       matrix:
         include:
           - name: "g++-13"
-            os: ubuntu-latest
+            os: ubuntu-24.04
             packages: "g++-13"
             toolset: "gcc-13"
-          - name: "clang-15"
-            os: ubuntu-latest
-            packages: "clang-15"
-            toolset: "clang-15"
+            cxxstd: 11,14,17,20,2b
+          - name: "clang-19"
+            os: ubuntu-24.04
+            packages: "clang-19"
+            toolset: "clang-19"
+            cxxstd: 11,14,17,20,2b
           - name: "xcode"
             os: macos-latest
             toolset: "clang"
+            cxxstd: 11,14,17,20,2b
     runs-on: ${{matrix.os}}
     steps:
       - uses: actions/checkout@main
-      - name: Install
+      - name: Install packages
         if: matrix.packages
         run: |
-          sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y
           sudo apt-get -o Acquire::Retries=3 update -y
           sudo apt-get -o Acquire::Retries=3 -y install ${{matrix.packages}}
-      - name: Setup
+      - 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: $REF
-          BOOST_BRANCH=develop && ( test "${GITHUB_REF_NAME}" == "master" || test "${GITHUB_REF_NAME}" == "modular" ) && BOOST_BRANCH=${GITHUB_REF_NAME} || true
-          BOOST_GIT=https://github.com/${GITHUB_REPOSITORY/sort/boost}.git
-          echo BOOST_GIT: ${BOOST_GIT}
-          echo BOOST_BRANCH: ${BOOST_BRANCH}
+          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          echo BOOST_BRANCH: $BOOST_BRANCH
           cd ..
-          git clone -b "${BOOST_BRANCH}" --depth 1 "${BOOST_GIT}" boost-root
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
           cd boost-root
-          git submodule update --init --jobs 3 tools/boostdep libs/assert libs/config libs/core libs/test libs/sort
-          python tools/boostdep/depinst/depinst.py -X test -g "--jobs 3" test
-          python tools/boostdep/depinst/depinst.py -X test -g "--jobs 3" sort
-          rm -rf libs/sort/*
-          cp -r $GITHUB_WORKSPACE/* libs/sort
+          cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
+          git submodule update --init tools/boostdep
+          python3 tools/boostdep/depinst/depinst.py --git_args "--jobs 3" $LIBRARY
           ./bootstrap.sh
           ./b2 -d0 headers
-      - name: Test
+      - name: Run tests
         run: |
           cd ../boost-root
-          ./b2 -j3 libs/sort/test toolset=${{matrix.toolset}} cxxstd=11,14,17,20
+          ./b2 -j3 libs/$LIBRARY/test toolset=${{matrix.toolset}} cxxstd=${{matrix.cxxstd}} variant=debug,release
+
+  posix-cmake-subdir:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+          - os: macos-latest
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        if: matrix.install
+        run: sudo apt install ${{matrix.install}}
+
+      - 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 --git_args "--jobs 3" $LIBRARY
+
+      - name: Use library with add_subdirectory
+        run: |
+          cd ../boost-root/libs/$LIBRARY/test/cmake_subdir_test
+          mkdir __build__ && cd __build__
+          cmake ..
+          cmake --build .
+          ctest --output-on-failure --no-tests=error
+
+  posix-cmake-install:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+          - os: macos-latest
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        if: matrix.install
+        run: sudo apt install ${{matrix.install}}
+
+      - 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 --git_args "--jobs 3" $LIBRARY
+
+      - name: Configure
+        run: |
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_INCLUDE_LIBRARIES=$LIBRARY -DCMAKE_INSTALL_PREFIX=~/.local ..
+
+      - 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 -DCMAKE_INSTALL_PREFIX=~/.local ..
+          cmake --build .
+          ctest --output-on-failure --no-tests=error
+
+  posix-cmake-test:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+          - os: macos-latest
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install packages
+        if: matrix.install
+        run: sudo apt install ${{matrix.install}}
+
+      - 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 --git_args "--jobs 3" $LIBRARY
+
+      - name: Configure
+        run: |
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_INCLUDE_LIBRARIES=$LIBRARY -DBUILD_TESTING=ON ..
+
+      - 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
diff --git a/test/cmake_install_test/CMakeLists.txt b/test/cmake_install_test/CMakeLists.txt
new file mode 100644
index 0000000..60e8202
--- /dev/null
+++ b/test/cmake_install_test/CMakeLists.txt
@@ -0,0 +1,17 @@
+# Copyright 2018, 2019 Peter Dimov
+# 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)
+
+project(cmake_install_test LANGUAGES CXX)
+
+find_package(boost_sort REQUIRED)
+
+add_executable(main main.cpp)
+target_link_libraries(main Boost::sort)
+
+enable_testing()
+add_test(main main)
+
+add_custom_target(check VERBATIM COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)
diff --git a/test/cmake_install_test/main.cpp b/test/cmake_install_test/main.cpp
new file mode 100644
index 0000000..5e04369
--- /dev/null
+++ b/test/cmake_install_test/main.cpp
@@ -0,0 +1,8 @@
+#include <boost/sort/spreadsort/integer_sort.hpp>
+
+int main()
+{
+    int v[] = { 1, 2, 3, 0 };
+    boost::sort::spreadsort::integer_sort( v + 0, v + 4 );
+    return v[ 0 ];
+}
diff --git a/test/cmake_subdir_test/CMakeLists.txt b/test/cmake_subdir_test/CMakeLists.txt
new file mode 100644
index 0000000..3a9a009
--- /dev/null
+++ b/test/cmake_subdir_test/CMakeLists.txt
@@ -0,0 +1,18 @@
+# Copyright 2018, 2019 Peter Dimov
+# 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)
+
+project(cmake_subdir_test LANGUAGES CXX)
+
+set(BOOST_INCLUDE_LIBRARIES sort)
+add_subdirectory(../../../.. boostorg/boost)
+
+add_executable(main main.cpp)
+target_link_libraries(main Boost::sort)
+
+enable_testing()
+add_test(main main)
+
+add_custom_target(check VERBATIM COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)
diff --git a/test/cmake_subdir_test/main.cpp b/test/cmake_subdir_test/main.cpp
new file mode 100644
index 0000000..5e04369
--- /dev/null
+++ b/test/cmake_subdir_test/main.cpp
@@ -0,0 +1,8 @@
+#include <boost/sort/spreadsort/integer_sort.hpp>
+
+int main()
+{
+    int v[] = { 1, 2, 3, 0 };
+    boost::sort::spreadsort::integer_sort( v + 0, v + 4 );
+    return v[ 0 ];
+}