From b21de511c334e8a68d16db31da433a67eda3eda9 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Wed, 25 Mar 2026 18:30:38 +0000
Subject: [PATCH 1/9] support import std

---
 CMakeLists.txt                                | 45 +++++++++++++------
 include/boost/stacktrace/detail/addr_base.hpp |  2 +
 .../boost/stacktrace/detail/frame_decl.hpp    |  2 +
 .../boost/stacktrace/detail/frame_unwind.ipp  |  2 +
 .../boost/stacktrace/detail/to_dec_array.hpp  |  2 +
 .../boost/stacktrace/detail/to_hex_array.hpp  |  2 +
 .../boost/stacktrace/detail/void_ptr_cast.hpp |  2 +
 include/boost/stacktrace/frame.hpp            |  2 +
 include/boost/stacktrace/safe_dump_to.hpp     |  2 +
 include/boost/stacktrace/stacktrace.hpp       |  2 +
 include/boost/stacktrace/stacktrace_fwd.hpp   |  2 +
 modules/boost_stacktrace_addr2line.cppm       |  6 +++
 modules/boost_stacktrace_backtrace.cppm       |  6 +++
 modules/boost_stacktrace_basic.cppm           |  6 +++
 modules/boost_stacktrace_dump.cppm            |  9 +++-
 modules/boost_stacktrace_noop.cppm            |  6 +++
 .../samples/usage_sample_from_exception.cpp   |  5 ++-
 17 files changed, 86 insertions(+), 17 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 909a353e..625f2af6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,18 +7,24 @@ cmake_minimum_required(VERSION 3.8...4.20)
 
 project(boost_stacktrace VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX)
 
-function(stacktrace_add_module name)
+function(stacktrace_add_module name import_std)
   target_sources(${name}
     PUBLIC
       FILE_SET CXX_MODULES
       BASE_DIRS ${CMAKE_CURRENT_LIST_DIR}/modules
       FILES ${CMAKE_CURRENT_LIST_DIR}/modules/${name}.cppm
   )
-  target_compile_features(${name} PUBLIC cxx_std_23)
   target_compile_definitions(${name} PUBLIC BOOST_USE_MODULES)
+
+  if(${import_std})
+    target_compile_features(${name} PUBLIC cxx_std_23)
+    target_compile_definitions(${name} PRIVATE BOOST_STACKTRACE_USE_STD_MODULE)
+  else()
+    target_compile_features(${name} PUBLIC cxx_std_20)
+  endif()
 endfunction()
 
-function(stacktrace_add_library suffix opt public_libs libs defs add_module)
+function(stacktrace_add_library suffix opt public_libs libs defs add_module import_std)
 
   if(NOT opt)
     return()
@@ -50,7 +56,7 @@ function(stacktrace_add_library suffix opt public_libs libs defs add_module)
   )
 
   if (add_module)
-    stacktrace_add_module(boost_stacktrace_${suffix})
+    stacktrace_add_module(boost_stacktrace_${suffix} ${import_std})
   else()
     target_sources(boost_stacktrace_${suffix}
       PRIVATE
@@ -129,23 +135,33 @@ else()
   set(_enable_non_noop_backend FALSE)
 endif()
 
-if(NOT BOOST_USE_MODULES)
+if(BOOST_USE_MODULES)
+  if (CMAKE_CXX_STANDARD AND CMAKE_CXX_STANDARD IN_LIST CMAKE_CXX_COMPILER_IMPORT_STD AND CMAKE_CXX_MODULE_STD)
+    message(STATUS "Using `import std;`")
+    set(__import_std ON)
+  else()
+    message(STATUS "`import std;` is not available")
+    set(__import_std OFF)
+  endif()
+  unset(__standard)
+else()
   set(BOOST_USE_MODULES OFF)
+  set(__import_std OFF)
 endif()
 
-stacktrace_add_library(dump ${_enable_non_noop_backend} "" "" "" ${BOOST_USE_MODULES})
-stacktrace_add_library(noop ${BOOST_STACKTRACE_ENABLE_NOOP} "" "" "" ${BOOST_USE_MODULES})
-stacktrace_add_library(backtrace ${BOOST_STACKTRACE_ENABLE_BACKTRACE} Boost::stacktrace_dump "backtrace;${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES})
-stacktrace_add_library(addr2line ${BOOST_STACKTRACE_ENABLE_ADDR2LINE} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES})
-stacktrace_add_library(basic ${BOOST_STACKTRACE_ENABLE_BASIC} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES})
-stacktrace_add_library(windbg ${BOOST_STACKTRACE_ENABLE_WINDBG} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1" ${BOOST_USE_MODULES})
-stacktrace_add_library(windbg_cached ${BOOST_STACKTRACE_ENABLE_WINDBG_CACHED} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1" ${BOOST_USE_MODULES})
+stacktrace_add_library(dump ${_enable_non_noop_backend} "" "" "" ${BOOST_USE_MODULES} ${__import_std})
+stacktrace_add_library(noop ${BOOST_STACKTRACE_ENABLE_NOOP} "" "" "" ${BOOST_USE_MODULES} ${__import_std})
+stacktrace_add_library(backtrace ${BOOST_STACKTRACE_ENABLE_BACKTRACE} Boost::stacktrace_dump "backtrace;${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES} ${__import_std})
+stacktrace_add_library(addr2line ${BOOST_STACKTRACE_ENABLE_ADDR2LINE} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES} ${__import_std})
+stacktrace_add_library(basic ${BOOST_STACKTRACE_ENABLE_BASIC} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES} ${__import_std})
+stacktrace_add_library(windbg ${BOOST_STACKTRACE_ENABLE_WINDBG} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1" ${BOOST_USE_MODULES} ${__import_std})
+stacktrace_add_library(windbg_cached ${BOOST_STACKTRACE_ENABLE_WINDBG_CACHED} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1" ${BOOST_USE_MODULES} ${__import_std})
 
 # boost_stacktrace, default library
 
 if(BOOST_USE_MODULES)
   add_library(boost_stacktrace)
-  stacktrace_add_module(boost_stacktrace boost_stacktrace)
+  stacktrace_add_module(boost_stacktrace ${__import_std})
   set(__scope PUBLIC)
 
   foreach(backend noop backtrace addr2line basic windbg windbg_cached)
@@ -157,6 +173,7 @@ else()
   add_library(boost_stacktrace INTERFACE)
   set(__scope INTERFACE)
 endif()
+unset(__import_std)
 
 target_include_directories(boost_stacktrace ${__scope} "${CMAKE_CURRENT_LIST_DIR}/include")
 add_library(Boost::stacktrace ALIAS boost_stacktrace)
@@ -182,7 +199,7 @@ target_link_libraries(boost_stacktrace ${__scope} Boost::stacktrace_${__default_
 
 # Boost::stacktrace_from_exception is never the default
 if(_enable_non_noop_backend)
-  stacktrace_add_library(from_exception ${BOOST_STACKTRACE_ENABLE_FROM_EXCEPTION} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" FALSE)
+  stacktrace_add_library(from_exception ${BOOST_STACKTRACE_ENABLE_FROM_EXCEPTION} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" FALSE FALSE)
   unset(_enable_non_noop_backend)
 endif()
 
diff --git a/include/boost/stacktrace/detail/addr_base.hpp b/include/boost/stacktrace/detail/addr_base.hpp
index b16ac2ba..736cc6fa 100644
--- a/include/boost/stacktrace/detail/addr_base.hpp
+++ b/include/boost/stacktrace/detail/addr_base.hpp
@@ -12,10 +12,12 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <fstream>
 #include <sstream>
 #include <cstdint>
 #include <cstdlib>
+#endif
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/frame_decl.hpp b/include/boost/stacktrace/detail/frame_decl.hpp
index 28ce5645..9a506fd0 100644
--- a/include/boost/stacktrace/detail/frame_decl.hpp
+++ b/include/boost/stacktrace/detail/frame_decl.hpp
@@ -15,7 +15,9 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <string>
+#endif
 
 #if !defined(BOOST_USE_MODULES)
 #include <boost/stacktrace/safe_dump_to.hpp>
diff --git a/include/boost/stacktrace/detail/frame_unwind.ipp b/include/boost/stacktrace/detail/frame_unwind.ipp
index 5a7cbea1..5401b5fb 100644
--- a/include/boost/stacktrace/detail/frame_unwind.ipp
+++ b/include/boost/stacktrace/detail/frame_unwind.ipp
@@ -20,7 +20,9 @@
 #include <boost/stacktrace/detail/addr_base.hpp>
 #include <boost/core/demangle.hpp>
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <cstdio>
+#endif
 
 #ifdef BOOST_STACKTRACE_USE_BACKTRACE
 #   include <boost/stacktrace/detail/libbacktrace_impls.hpp>
diff --git a/include/boost/stacktrace/detail/to_dec_array.hpp b/include/boost/stacktrace/detail/to_dec_array.hpp
index dc5372e3..9db5a979 100644
--- a/include/boost/stacktrace/detail/to_dec_array.hpp
+++ b/include/boost/stacktrace/detail/to_dec_array.hpp
@@ -12,8 +12,10 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <array>
 #include <cstddef>  // std::size_t
+#endif
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/to_hex_array.hpp b/include/boost/stacktrace/detail/to_hex_array.hpp
index ee9a6b15..957d389f 100644
--- a/include/boost/stacktrace/detail/to_hex_array.hpp
+++ b/include/boost/stacktrace/detail/to_hex_array.hpp
@@ -12,8 +12,10 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <array>
 #include <type_traits>
+#endif
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/void_ptr_cast.hpp b/include/boost/stacktrace/detail/void_ptr_cast.hpp
index f275ecfb..ebbfe1e2 100644
--- a/include/boost/stacktrace/detail/void_ptr_cast.hpp
+++ b/include/boost/stacktrace/detail/void_ptr_cast.hpp
@@ -13,7 +13,9 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <type_traits>
+#endif
 
 #if defined(__GNUC__) && defined(__GNUC_MINOR__) && (__GNUC__ * 100 + __GNUC_MINOR__ > 301)
 #   pragma GCC system_header
diff --git a/include/boost/stacktrace/frame.hpp b/include/boost/stacktrace/frame.hpp
index 5402e949..0266f81a 100644
--- a/include/boost/stacktrace/frame.hpp
+++ b/include/boost/stacktrace/frame.hpp
@@ -15,8 +15,10 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <iosfwd>
 #include <string>
+#endif
 
 #include <boost/stacktrace/detail/frame_decl.hpp>
 #include <boost/stacktrace/detail/push_options.h>
diff --git a/include/boost/stacktrace/safe_dump_to.hpp b/include/boost/stacktrace/safe_dump_to.hpp
index bd47710a..1e8726d5 100644
--- a/include/boost/stacktrace/safe_dump_to.hpp
+++ b/include/boost/stacktrace/safe_dump_to.hpp
@@ -19,7 +19,9 @@
 #   pragma once
 #endif
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <cstddef>
+#endif
 
 #if defined(BOOST_WINDOWS)
 #include <boost/winapi/config.hpp>
diff --git a/include/boost/stacktrace/stacktrace.hpp b/include/boost/stacktrace/stacktrace.hpp
index 5be946f5..767d63d8 100644
--- a/include/boost/stacktrace/stacktrace.hpp
+++ b/include/boost/stacktrace/stacktrace.hpp
@@ -18,6 +18,7 @@
 #include <boost/core/no_exceptions_support.hpp>
 #include <boost/container_hash/hash_fwd.hpp>
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <iosfwd>
 #include <string>
 #include <vector>
@@ -25,6 +26,7 @@
 #ifndef BOOST_NO_CXX11_HDR_TYPE_TRAITS
 #   include <type_traits>
 #endif
+#endif
 
 #include <boost/stacktrace/stacktrace_fwd.hpp>
 #include <boost/stacktrace/detail/frame_decl.hpp>
diff --git a/include/boost/stacktrace/stacktrace_fwd.hpp b/include/boost/stacktrace/stacktrace_fwd.hpp
index 00735c23..035ea338 100644
--- a/include/boost/stacktrace/stacktrace_fwd.hpp
+++ b/include/boost/stacktrace/stacktrace_fwd.hpp
@@ -11,8 +11,10 @@
 
 #if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
+#ifndef BOOST_STACKTRACE_USE_STD_MODULE
 #include <cstddef>
 #include <memory>
+#endif
 
 /// @file stacktrace_fwd.hpp This header contains only forward declarations of
 /// boost::stacktrace::frame, boost::stacktrace::basic_stacktrace, boost::stacktrace::stacktrace
diff --git a/modules/boost_stacktrace_addr2line.cppm b/modules/boost_stacktrace_addr2line.cppm
index a521b4ee..4e2f8630 100644
--- a/modules/boost_stacktrace_addr2line.cppm
+++ b/modules/boost_stacktrace_addr2line.cppm
@@ -14,6 +14,7 @@ module;
 #include <boost/container_hash/hash_fwd.hpp>
 #include <boost/predef.h>
 
+#if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <array>
 #include <iosfwd>
 #include <string>
@@ -25,12 +26,17 @@ module;
 #include <string>
 #include <type_traits>
 #include <cxxabi.h>
+#endif
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
 #define BOOST_STACKTRACE_LINK
 
 export module boost.stacktrace.addr2line;
 
+#if defined(BOOST_STACKTRACE_USE_STD_MODULE)
+import std;
+#endif
+
 import boost.stacktrace.dump;
 
 #ifdef __clang__
diff --git a/modules/boost_stacktrace_backtrace.cppm b/modules/boost_stacktrace_backtrace.cppm
index 459bfd2c..0c96a5a7 100644
--- a/modules/boost_stacktrace_backtrace.cppm
+++ b/modules/boost_stacktrace_backtrace.cppm
@@ -16,6 +16,7 @@ module;
 
 #include <backtrace.h>
 
+#if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <array>
 #include <iosfwd>
 #include <string>
@@ -27,6 +28,7 @@ module;
 #include <string>
 #include <type_traits>
 #include <cxxabi.h>
+#endif
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
 #define BOOST_STACKTRACE_LINK
@@ -37,6 +39,10 @@ module;
 
 export module boost.stacktrace.backtrace;
 
+#if defined(BOOST_STACKTRACE_USE_STD_MODULE)
+import std;
+#endif
+
 import boost.stacktrace.dump;
 
 #ifdef __clang__
diff --git a/modules/boost_stacktrace_basic.cppm b/modules/boost_stacktrace_basic.cppm
index 5eaaaf7a..460ff34e 100644
--- a/modules/boost_stacktrace_basic.cppm
+++ b/modules/boost_stacktrace_basic.cppm
@@ -14,6 +14,7 @@ module;
 #include <boost/container_hash/hash_fwd.hpp>
 #include <boost/predef.h>
 
+#if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <array>
 #include <iosfwd>
 #include <string>
@@ -25,12 +26,17 @@ module;
 #include <string>
 #include <type_traits>
 #include <cxxabi.h>
+#endif
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
 #define BOOST_STACKTRACE_LINK
 
 export module boost.stacktrace.basic;
 
+#if defined(BOOST_STACKTRACE_USE_STD_MODULE)
+import std;
+#endif
+
 import boost.stacktrace.dump;
 
 #ifdef __clang__
diff --git a/modules/boost_stacktrace_dump.cppm b/modules/boost_stacktrace_dump.cppm
index ae666d13..bba020c0 100644
--- a/modules/boost_stacktrace_dump.cppm
+++ b/modules/boost_stacktrace_dump.cppm
@@ -10,9 +10,12 @@ module;
 #include <boost/config.hpp>
 #include <boost/predef.h>
 
+#if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
+#include <stdio.h>
+#endif
+
 #include <fcntl.h>
 #include <unwind.h>
-#include <stdio.h>
 #include <sys/stat.h>
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
@@ -24,6 +27,10 @@ module;
 
 export module boost.stacktrace.dump;
 
+#if defined(BOOST_STACKTRACE_USE_STD_MODULE)
+import std;
+#endif
+
 #ifdef __clang__
 #   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
 #endif
diff --git a/modules/boost_stacktrace_noop.cppm b/modules/boost_stacktrace_noop.cppm
index 050251db..633612a1 100644
--- a/modules/boost_stacktrace_noop.cppm
+++ b/modules/boost_stacktrace_noop.cppm
@@ -9,14 +9,20 @@ module;
 
 #include <boost/config.hpp>
 
+#if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <vector>
 #include <memory>
+#endif
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
 #define BOOST_STACKTRACE_LINK
 
 export module boost.stacktrace.noop;
 
+#if defined(BOOST_STACKTRACE_USE_STD_MODULE)
+import std;
+#endif
+
 #ifdef __clang__
 #   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
 #endif
diff --git a/modules/samples/usage_sample_from_exception.cpp b/modules/samples/usage_sample_from_exception.cpp
index 5cac1f2a..9461a326 100644
--- a/modules/samples/usage_sample_from_exception.cpp
+++ b/modules/samples/usage_sample_from_exception.cpp
@@ -6,7 +6,7 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #include <iostream>
-#include <stdexcept>
+#include <map>
 
 #include <boost/config.hpp>
 
@@ -15,7 +15,8 @@
 namespace {
 
 BOOST_NOINLINE void foo() {
-    throw std::logic_error{"Foo"};
+    std::map<int, int> m;
+    m.at(1);
 }
 
 BOOST_NOINLINE void bar() {

From f9ecb7ade6b1478a5b70e29f78e320b780e09b77 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sun, 29 Mar 2026 11:48:40 +0000
Subject: [PATCH 2/9] add import std CI

---
 .github/workflows/ci.yml | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 659a4383..82aec04d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -94,10 +94,28 @@ jobs:
           make -j"$(nproc)"
           make install
 
+      - name: Run modules tests
+        if: ${{matrix.toolset == 'clang-19'}}
+        run: |
+          cd ../boost-root/libs/$LIBRARY
+          cmake -S test/cmake_subdir_test \
+                -B build_module \
+                -GNinja \
+                -DBOOST_USE_MODULES=1 \
+                -DBUILD_TESTING=1 \
+                -DCMAKE_CXX_STANDARD=23 \
+                -DCMAKE_CXX_COMPILER=${{matrix.compiler}} \
+                -DCMAKE_CXX_FLAGS="-stdlib=libc++ -I/home/runner/.local/include" \
+                -DCMAKE_EXE_LINKER_FLAGS="-L/home/runner/.local" \
+                -DCMAKE_CXX_MODULE_STD=ON \
+                -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=0e5b6991-d74f-4b3d-a41c-cf096e0b2508
+          cmake --build build_module
+          ctest --test-dir build_module -VV
+          rm -rf build_module
+
       - name: Run modules tests without 'import std;'
         if: ${{matrix.toolset == 'clang-19'}}
         run: |
-          pwd
           cd ../boost-root/libs/$LIBRARY
           cmake -S test/cmake_subdir_test \
                 -B build_module \

From b140f0bc54e71c799ad57a8ad7c2ff25c752c11e Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sun, 29 Mar 2026 12:02:48 +0000
Subject: [PATCH 3/9] try fix noop module

---
 modules/boost_stacktrace_noop.cppm | 1 +
 1 file changed, 1 insertion(+)

diff --git a/modules/boost_stacktrace_noop.cppm b/modules/boost_stacktrace_noop.cppm
index 633612a1..3519d955 100644
--- a/modules/boost_stacktrace_noop.cppm
+++ b/modules/boost_stacktrace_noop.cppm
@@ -8,6 +8,7 @@
 module;
 
 #include <boost/config.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
 
 #if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <vector>

From 801cad4339f1d50996070ef8b63fbc1de4dee561 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sat, 11 Apr 2026 14:52:33 +0000
Subject: [PATCH 4/9] fix build

---
 include/boost/stacktrace/safe_dump_to.hpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/boost/stacktrace/safe_dump_to.hpp b/include/boost/stacktrace/safe_dump_to.hpp
index 7e2566b9..2947c85e 100644
--- a/include/boost/stacktrace/safe_dump_to.hpp
+++ b/include/boost/stacktrace/safe_dump_to.hpp
@@ -19,9 +19,11 @@
 #   pragma once
 #endif
 
-#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT) && !defined(BOOST_STACKTRACE_USE_STD_MODULE)
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <cstddef>
-#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT) && !defined(BOOST_STACKTRACE_USE_STD_MODULE)
+#endif // !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 
 #if defined(BOOST_WINDOWS)
 #include <boost/winapi/config.hpp>

From aa8294a905538839ab677f016843e8f49ba577d8 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sat, 2 May 2026 07:37:06 +0000
Subject: [PATCH 5/9] use env

---
 .github/workflows/ci.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9c677720..5a7e5deb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -105,8 +105,8 @@ jobs:
                 -DBUILD_TESTING=1 \
                 -DCMAKE_CXX_STANDARD=23 \
                 -DCMAKE_CXX_COMPILER=${{matrix.compiler}} \
-                -DCMAKE_CXX_FLAGS="-stdlib=libc++ -I/home/runner/.local/include" \
-                -DCMAKE_EXE_LINKER_FLAGS="-L/home/runner/.local" \
+                -DCMAKE_CXX_FLAGS="-stdlib=libc++ -I$HOME/.local/include" \
+                -DCMAKE_EXE_LINKER_FLAGS="-L$HOME/.local" \
                 -DCMAKE_CXX_MODULE_STD=ON \
                 -DCMAKE_EXPERIMENTAL_CXX_IMPORT_STD=0e5b6991-d74f-4b3d-a41c-cf096e0b2508
           cmake --build build_module

From 88c70019b465c51b51a8eef7c07141fbffc8f80c Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sat, 2 May 2026 07:49:05 +0000
Subject: [PATCH 6/9] better check

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 00d50733..87318c80 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -136,7 +136,7 @@ else()
 endif()
 
 if(BOOST_USE_MODULES)
-  if (CMAKE_CXX_STANDARD AND CMAKE_CXX_STANDARD IN_LIST CMAKE_CXX_COMPILER_IMPORT_STD AND CMAKE_CXX_MODULE_STD)
+  if ((CMAKE_CXX_STANDARD IN_LIST CMAKE_CXX_COMPILER_IMPORT_STD) AND CMAKE_CXX_MODULE_STD)
     message(STATUS "Using `import std;`")
     set(__import_std ON)
   else()

From 3291c638ffb62ae2ab23ef757bb9676a34ce0db4 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sat, 2 May 2026 07:53:02 +0000
Subject: [PATCH 7/9] fix warning

---
 modules/samples/usage_sample_from_exception.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/samples/usage_sample_from_exception.cpp b/modules/samples/usage_sample_from_exception.cpp
index 9461a326..832e8796 100644
--- a/modules/samples/usage_sample_from_exception.cpp
+++ b/modules/samples/usage_sample_from_exception.cpp
@@ -16,7 +16,7 @@ namespace {
 
 BOOST_NOINLINE void foo() {
     std::map<int, int> m;
-    m.at(1);
+    std::ignore = m.at(1);
 }
 
 BOOST_NOINLINE void bar() {

From f966b6a1e63d1fbdaef2f8e65db5e0235547bef9 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <33493672+fdr400@users.noreply.github.com>
Date: Tue, 5 May 2026 20:29:10 +0300
Subject: [PATCH 8/9] feat boost.stacktrace: C++20 modules support (#230)

- Introduce `boost.stacktrace_dump` module for safe_dump interface
- Introduce `boost.stacktrace_<backend>` module for each unwind/collect implementation method
- Introduce `boost.stacktrace` module exposing best available backend implementation

Also many tests was added for checking all available backend build and also header only library version
Moreover, there are some checks for `Boost::stacktrace_<backend>` and  `Boost::stacktrace_from_exception` compatibility

---------

Co-authored-by: Fedor Osetrov <fdr400@Fedors-MacBook-Pro.local>
---
 .github/workflows/ci.yml                      | 57 ++++++++++++++--
 .gitignore                                    |  3 +
 CMakeLists.txt                                | 67 ++++++++++++++-----
 include/boost/stacktrace.hpp                  |  7 +-
 .../stacktrace/detail/addr2line_impls.hpp     | 11 +--
 include/boost/stacktrace/detail/addr_base.hpp |  2 +
 .../stacktrace/detail/addr_base_msvc.hpp      |  2 +
 .../stacktrace/detail/backend_config.hpp      | 24 +++++++
 .../boost/stacktrace/detail/collect_msvc.ipp  |  6 +-
 .../stacktrace/detail/collect_unwind.ipp      |  6 +-
 include/boost/stacktrace/detail/config.hpp    | 26 +++++++
 .../boost/stacktrace/detail/frame_decl.hpp    | 19 +++++-
 .../boost/stacktrace/detail/frame_msvc.ipp    | 19 +++---
 .../boost/stacktrace/detail/frame_unwind.ipp  |  9 ++-
 .../stacktrace/detail/libbacktrace_impls.hpp  |  9 ++-
 .../detail/location_from_symbol.hpp           |  3 +
 .../stacktrace/detail/safe_dump_posix.ipp     |  5 +-
 .../boost/stacktrace/detail/safe_dump_win.ipp |  6 +-
 .../boost/stacktrace/detail/to_dec_array.hpp  |  2 +
 .../boost/stacktrace/detail/to_hex_array.hpp  |  2 +
 .../stacktrace/detail/try_dec_convert.hpp     |  2 +
 .../boost/stacktrace/detail/void_ptr_cast.hpp |  4 +-
 include/boost/stacktrace/frame.hpp            | 12 +++-
 include/boost/stacktrace/safe_dump_to.hpp     | 23 ++++++-
 include/boost/stacktrace/stacktrace.hpp       | 20 +++++-
 include/boost/stacktrace/stacktrace_fwd.hpp   | 11 +++
 include/boost/stacktrace/this_thread.hpp      | 11 ++-
 modules/boost_stacktrace.cppm                 |  9 +++
 modules/boost_stacktrace_addr2line.cppm       | 49 ++++++++++++++
 modules/boost_stacktrace_backtrace.cppm       | 47 +++++++++++++
 modules/boost_stacktrace_basic.cppm           | 44 ++++++++++++
 modules/boost_stacktrace_dump.cppm            | 45 +++++++++++++
 modules/boost_stacktrace_noop.cppm            | 33 +++++++++
 modules/boost_stacktrace_windbg.cppm          | 29 ++++++++
 modules/boost_stacktrace_windbg_cached.cppm   | 30 +++++++++
 modules/samples/usage_sample.cpp              | 34 ++++++++++
 .../samples/usage_sample_from_exception.cpp   | 34 ++++++++++
 test/cmake_subdir_test/CMakeLists.txt         | 46 ++++++++++---
 test/cmake_subdir_test/main.cpp               |  2 +-
 test/test.cpp                                 |  5 +-
 test/test_from_exception.cpp                  |  4 +-
 test/test_from_exception_none.cpp             |  4 +-
 test/test_torture.cpp                         |  2 +-
 test/test_trivial.cpp                         |  4 +-
 test/test_void_ptr_cast.cpp                   |  4 +-
 45 files changed, 709 insertions(+), 84 deletions(-)
 create mode 100644 .gitignore
 create mode 100644 include/boost/stacktrace/detail/backend_config.hpp
 create mode 100644 include/boost/stacktrace/detail/config.hpp
 create mode 100644 modules/boost_stacktrace.cppm
 create mode 100644 modules/boost_stacktrace_addr2line.cppm
 create mode 100644 modules/boost_stacktrace_backtrace.cppm
 create mode 100644 modules/boost_stacktrace_basic.cppm
 create mode 100644 modules/boost_stacktrace_dump.cppm
 create mode 100644 modules/boost_stacktrace_noop.cppm
 create mode 100644 modules/boost_stacktrace_windbg.cppm
 create mode 100644 modules/boost_stacktrace_windbg_cached.cppm
 create mode 100644 modules/samples/usage_sample.cpp
 create mode 100644 modules/samples/usage_sample_from_exception.cpp

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fe74c890..79eec1e2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -27,10 +27,21 @@ jobs:
           - toolset: gcc-9
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-22.04
-            install: g++-9
+            install: [g++-9]
           - toolset: clang-15
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-22.04
+          - toolset: clang-19
+            compiler: clang++-19
+            cxxstd: "20"
+            os: ubuntu-24.04
+            install: &cxx19
+              - clang-19
+              - llvm-19
+              - libclang-rt-19-dev
+              - libc++-19-dev
+              - libc++abi-19-dev
+              - clang-tools-19
           # TODO: fix and uncomment
           #- toolset: clang
           #  cxxstd: "03,11,14,17,2a"
@@ -45,7 +56,7 @@ jobs:
 
       - name: Install packages
         if: matrix.install
-        run: sudo apt install ${{matrix.install}}
+        run: sudo apt install -y ${{join(matrix.install, ' ')}}
 
       - name: Setup Boost
         run: |
@@ -71,6 +82,35 @@ jobs:
           ./bootstrap.sh
           ./b2 -d0 headers
           ./b2 -j4 variant=debug tools/inspect
+      
+      - name: Build libbacktrace
+        if: ${{matrix.toolset == 'clang-19'}}
+        run: |
+          # libc++ do not have bundled libbacktrace implementation
+          git clone --depth=1 https://github.com/ianlancetaylor/libbacktrace.git
+          cd libbacktrace
+          CC=clang-19 OBJCOPY=/usr/bin/llvm-objcopy NM=/usr/bin/llvm-nm \
+            ./configure --prefix="$HOME/.local" --with-system-libunwind
+          make -j"$(nproc)"
+          make install
+
+      - name: Run modules tests without 'import std;'
+        if: ${{matrix.toolset == 'clang-19'}}
+        run: |
+          pwd
+          cd ../boost-root/libs/$LIBRARY
+          cmake -S test/cmake_subdir_test \
+                -B build_module \
+                -GNinja \
+                -DBOOST_USE_MODULES=1 \
+                -DBUILD_TESTING=1 \
+                -DCMAKE_CXX_STANDARD=20 \
+                -DCMAKE_CXX_COMPILER=${{matrix.compiler}} \
+                -DCMAKE_CXX_FLAGS="-stdlib=libc++ -I$HOME/.local/include" \
+                -DCMAKE_EXE_LINKER_FLAGS="-L$HOME/.local"
+          cmake --build build_module
+          ctest --test-dir build_module -VV
+          rm -rf build_module
 
       - name: Run tests
         run: |
@@ -205,11 +245,14 @@ jobs:
 
       - name: Use library with add_subdirectory
         run: |
-          cd ../boost-root/libs/$LIBRARY/test/cmake_subdir_test
-          mkdir __build__ && cd __build__
-          cmake -DBUILD_SHARED_LIBS=${{matrix.shared}} ..
-          cmake --build .
-          ctest --output-on-failure --no-tests=error
+          cd ../boost-root/libs/$LIBRARY
+          cmake -S test/cmake_subdir_test -B __build__ \
+            -GNinja \
+            -DBUILD_SHARED_LIBS=${{matrix.shared}}
+
+          cmake --build __build__
+          ctest --test-dir __build__ --output-on-failure --no-tests=error
+          rm -rf __build__
 
   posix-cmake-install:
     strategy:
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 00000000..a77efcd9
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+build?*
+.cache
+.vscode
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d642defe..36c97e50 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,7 +7,18 @@ cmake_minimum_required(VERSION 3.8...4.20)
 
 project(boost_stacktrace VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX)
 
-function(stacktrace_add_library suffix opt public_libs libs defs)
+function(stacktrace_add_module name)
+  target_sources(${name}
+    PUBLIC
+      FILE_SET CXX_MODULES
+      BASE_DIRS "${CMAKE_CURRENT_LIST_DIR}/modules"
+      FILES "${CMAKE_CURRENT_LIST_DIR}/modules/${name}.cppm"
+  )
+  target_compile_features(${name} PUBLIC cxx_std_20)
+  target_compile_definitions(${name} PUBLIC BOOST_USE_MODULES)
+endfunction()
+
+function(stacktrace_add_library suffix opt public_libs libs defs add_module)
 
   if(NOT opt)
     return()
@@ -38,10 +49,14 @@ function(stacktrace_add_library suffix opt public_libs libs defs)
       ${defs}
   )
 
-  target_sources(boost_stacktrace_${suffix}
-    PRIVATE
-      ${CMAKE_CURRENT_LIST_DIR}/src/${suffix}.cpp
-  )
+  if (add_module)
+    stacktrace_add_module(boost_stacktrace_${suffix})
+  else()
+    target_sources(boost_stacktrace_${suffix}
+      PRIVATE
+        "${CMAKE_CURRENT_LIST_DIR}/src/${suffix}.cpp"
+    )
+  endif()
 
   if(BUILD_SHARED_LIBS)
     target_compile_definitions(boost_stacktrace_${suffix} PUBLIC BOOST_STACKTRACE_DYN_LINK)
@@ -110,24 +125,40 @@ if(BOOST_STACKTRACE_ENABLE_BACKTRACE OR
    BOOST_STACKTRACE_ENABLE_WINDBG_CACHED
   )
   set(_enable_non_noop_backend TRUE)
+else()
+  set(_enable_non_noop_backend FALSE)
 endif()
 
-if(_enable_non_noop_backend)
-  stacktrace_add_library(dump ON "" "" "")
+if(NOT BOOST_USE_MODULES)
+  set(BOOST_USE_MODULES OFF)
 endif()
-stacktrace_add_library(noop ${BOOST_STACKTRACE_ENABLE_NOOP} "" "" "")
-stacktrace_add_library(backtrace ${BOOST_STACKTRACE_ENABLE_BACKTRACE} Boost::stacktrace_dump "backtrace;${CMAKE_DL_LIBS}" "")
-stacktrace_add_library(addr2line ${BOOST_STACKTRACE_ENABLE_ADDR2LINE} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "")
-stacktrace_add_library(basic ${BOOST_STACKTRACE_ENABLE_BASIC} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "")
-stacktrace_add_library(windbg ${BOOST_STACKTRACE_ENABLE_WINDBG} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1")
-stacktrace_add_library(windbg_cached ${BOOST_STACKTRACE_ENABLE_WINDBG_CACHED} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1")
+
+stacktrace_add_library(dump ${_enable_non_noop_backend} "" "" "" ${BOOST_USE_MODULES})
+stacktrace_add_library(noop ${BOOST_STACKTRACE_ENABLE_NOOP} "" "" "" ${BOOST_USE_MODULES})
+stacktrace_add_library(backtrace ${BOOST_STACKTRACE_ENABLE_BACKTRACE} Boost::stacktrace_dump "backtrace;${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES})
+stacktrace_add_library(addr2line ${BOOST_STACKTRACE_ENABLE_ADDR2LINE} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES})
+stacktrace_add_library(basic ${BOOST_STACKTRACE_ENABLE_BASIC} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" ${BOOST_USE_MODULES})
+stacktrace_add_library(windbg ${BOOST_STACKTRACE_ENABLE_WINDBG} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1" ${BOOST_USE_MODULES})
+stacktrace_add_library(windbg_cached ${BOOST_STACKTRACE_ENABLE_WINDBG_CACHED} Boost::stacktrace_dump "dbgeng;ole32" "_GNU_SOURCE=1" ${BOOST_USE_MODULES})
 
 # boost_stacktrace, default library
 
-add_library(boost_stacktrace INTERFACE)
+if(BOOST_USE_MODULES)
+  add_library(boost_stacktrace)
+  stacktrace_add_module(boost_stacktrace boost_stacktrace)
+  set(__scope PUBLIC)
 
-target_include_directories(boost_stacktrace INTERFACE include)
+  foreach(backend noop backtrace addr2line basic windbg windbg_cached)
+    if (TARGET boost_stacktrace_${backend})
+      target_compile_definitions(boost_stacktrace_${backend} INTERFACE BOOST_STACKTRACE_BACKEND_MODULE=${backend})
+    endif()
+  endforeach()
+else()
+  add_library(boost_stacktrace INTERFACE)
+  set(__scope INTERFACE)
+endif()
 
+target_include_directories(boost_stacktrace ${__scope} "${CMAKE_CURRENT_LIST_DIR}/include")
 add_library(Boost::stacktrace ALIAS boost_stacktrace)
 
 if(BOOST_STACKTRACE_ENABLE_WINDBG)
@@ -147,13 +178,13 @@ else()
 endif()
 
 message(STATUS "Boost.stacktrace default backend: ${__default_stacktrace_backend}")
-target_link_libraries(boost_stacktrace INTERFACE Boost::stacktrace_${__default_stacktrace_backend})
+target_link_libraries(boost_stacktrace ${__scope} Boost::stacktrace_${__default_stacktrace_backend})
 
 # Boost::stacktrace_from_exception is never the default
 if(_enable_non_noop_backend)
-  stacktrace_add_library(from_exception ${BOOST_STACKTRACE_ENABLE_FROM_EXCEPTION} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "")
-  unset(_enable_non_noop_backend)
+  stacktrace_add_library(from_exception ${BOOST_STACKTRACE_ENABLE_FROM_EXCEPTION} Boost::stacktrace_dump "${CMAKE_DL_LIBS}" "" FALSE)
 endif()
+unset(_enable_non_noop_backend)
 
 if(BUILD_TESTING)
   add_subdirectory(test)
diff --git a/include/boost/stacktrace.hpp b/include/boost/stacktrace.hpp
index 697102dc..036c3c0d 100644
--- a/include/boost/stacktrace.hpp
+++ b/include/boost/stacktrace.hpp
@@ -7,7 +7,10 @@
 #ifndef BOOST_STACKTRACE_HPP
 #define BOOST_STACKTRACE_HPP
 
-#include <boost/config.hpp>
+#include <boost/stacktrace/detail/backend_config.hpp>
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
@@ -17,4 +20,6 @@
 #include <boost/stacktrace/safe_dump_to.hpp>
 #include <boost/stacktrace/this_thread.hpp>
 
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #endif // BOOST_STACKTRACE_HPP
diff --git a/include/boost/stacktrace/detail/addr2line_impls.hpp b/include/boost/stacktrace/detail/addr2line_impls.hpp
index 255ea7f6..f2e3b293 100644
--- a/include/boost/stacktrace/detail/addr2line_impls.hpp
+++ b/include/boost/stacktrace/detail/addr2line_impls.hpp
@@ -12,18 +12,21 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/detail/addr_base.hpp>
-#include <boost/stacktrace/detail/to_hex_array.hpp>
-#include <boost/stacktrace/detail/to_dec_array.hpp>
-#include <boost/stacktrace/detail/try_dec_convert.hpp>
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <boost/core/demangle.hpp>
+
 #include <cstdio>
 #include <cstring>
 
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <signal.h>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
+#include <boost/stacktrace/detail/addr_base.hpp>
+#include <boost/stacktrace/detail/to_hex_array.hpp>
+#include <boost/stacktrace/detail/to_dec_array.hpp>
+#include <boost/stacktrace/detail/try_dec_convert.hpp>
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/addr_base.hpp b/include/boost/stacktrace/detail/addr_base.hpp
index b16ac2ba..5df86bcb 100644
--- a/include/boost/stacktrace/detail/addr_base.hpp
+++ b/include/boost/stacktrace/detail/addr_base.hpp
@@ -12,10 +12,12 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <fstream>
 #include <sstream>
 #include <cstdint>
 #include <cstdlib>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/addr_base_msvc.hpp b/include/boost/stacktrace/detail/addr_base_msvc.hpp
index 7d429871..34959131 100644
--- a/include/boost/stacktrace/detail/addr_base_msvc.hpp
+++ b/include/boost/stacktrace/detail/addr_base_msvc.hpp
@@ -12,6 +12,7 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <cstdio>
 #include <cstdint>
 #include <memory>
@@ -27,6 +28,7 @@
 #include <psapi.h>
 #undef WIN32_LEAN_AND_MEAN
 #endif
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 namespace boost { namespace stacktrace { namespace detail {
   inline std::uintptr_t get_own_proc_addr_base(const void* addr) {
diff --git a/include/boost/stacktrace/detail/backend_config.hpp b/include/boost/stacktrace/detail/backend_config.hpp
new file mode 100644
index 00000000..9e27eb60
--- /dev/null
+++ b/include/boost/stacktrace/detail/backend_config.hpp
@@ -0,0 +1,24 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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_STACKTRACE_DETAIL_BACKEND_CONFIG_HPP
+#define BOOST_STACKTRACE_DETAIL_BACKEND_CONFIG_HPP
+
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+# include <boost/config.hpp>
+# ifdef BOOST_HAS_PRAGMA_ONCE
+#  pragma once
+# endif
+#endif
+
+#include "boost/stacktrace/detail/config.hpp"
+
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_STACKTRACE_INTERFACE_UNIT) && !defined(BOOST_STACKTRACE_INTERNAL_BUILD_LIBS)
+    import boost.stacktrace.BOOST_STACKTRACE_BACKEND_MODULE;
+#endif
+
+#endif
diff --git a/include/boost/stacktrace/detail/collect_msvc.ipp b/include/boost/stacktrace/detail/collect_msvc.ipp
index 879d9d74..353a85d1 100644
--- a/include/boost/stacktrace/detail/collect_msvc.ipp
+++ b/include/boost/stacktrace/detail/collect_msvc.ipp
@@ -12,9 +12,11 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/safe_dump_to.hpp>
-
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <boost/winapi/stack_backtrace.hpp>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#include <boost/stacktrace/safe_dump_to.hpp>
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/collect_unwind.ipp b/include/boost/stacktrace/detail/collect_unwind.ipp
index b738e62e..7fcae4f7 100644
--- a/include/boost/stacktrace/detail/collect_unwind.ipp
+++ b/include/boost/stacktrace/detail/collect_unwind.ipp
@@ -12,8 +12,7 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/safe_dump_to.hpp>
-
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 // On iOS 32-bit ARM architecture _Unwind_Backtrace function doesn't exist, symbol is undefined.
 // Forcing libc backtrace() function usage.
 #include <boost/predef.h>
@@ -28,11 +27,14 @@
 #include <unwind.h>
 #endif
 #include <cstdio>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #if !defined(_GNU_SOURCE) && !defined(BOOST_STACKTRACE_GNU_SOURCE_NOT_REQUIRED) && !defined(BOOST_WINDOWS)
 #error "Boost.Stacktrace requires `_Unwind_Backtrace` function. Define `_GNU_SOURCE` macro or `BOOST_STACKTRACE_GNU_SOURCE_NOT_REQUIRED` if _Unwind_Backtrace is available without `_GNU_SOURCE`."
 #endif
 
+#include <boost/stacktrace/safe_dump_to.hpp>
+
 namespace boost { namespace stacktrace { namespace detail {
 
 #if !defined(BOOST_STACKTRACE_USE_LIBC_BACKTRACE_FUNCTION)
diff --git a/include/boost/stacktrace/detail/config.hpp b/include/boost/stacktrace/detail/config.hpp
new file mode 100644
index 00000000..031fb629
--- /dev/null
+++ b/include/boost/stacktrace/detail/config.hpp
@@ -0,0 +1,26 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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_STACKTRACE_DETAIL_CONFIG_HPP
+#define BOOST_STACKTRACE_DETAIL_CONFIG_HPP
+
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+# include <boost/config.hpp>
+# ifdef BOOST_HAS_PRAGMA_ONCE
+#  pragma once
+# endif
+#endif
+
+#ifdef BOOST_STACKTRACE_INTERFACE_UNIT
+# define BOOST_STACKTRACE_BEGIN_MODULE_EXPORT export {
+# define BOOST_STACKTRACE_END_MODULE_EXPORT }
+#else
+# define BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+# define BOOST_STACKTRACE_END_MODULE_EXPORT
+#endif
+
+#endif
diff --git a/include/boost/stacktrace/detail/frame_decl.hpp b/include/boost/stacktrace/detail/frame_decl.hpp
index 8920e212..64eaf623 100644
--- a/include/boost/stacktrace/detail/frame_decl.hpp
+++ b/include/boost/stacktrace/detail/frame_decl.hpp
@@ -7,14 +7,22 @@
 #ifndef BOOST_STACKTRACE_DETAIL_FRAME_DECL_HPP
 #define BOOST_STACKTRACE_DETAIL_FRAME_DECL_HPP
 
-#include <boost/config.hpp>
+#include <boost/stacktrace/detail/config.hpp>
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <string>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#if !defined(BOOST_USE_MODULES)
+#include <boost/stacktrace/safe_dump_to.hpp>
+#endif
 
-#include <boost/stacktrace/safe_dump_to.hpp> // boost::stacktrace::detail::native_frame_ptr_t
 #include <boost/stacktrace/detail/void_ptr_cast.hpp>
 
 #include <boost/stacktrace/detail/push_options.h>
@@ -22,6 +30,8 @@
 /// @file boost/stacktrace/detail/frame_decl.hpp
 /// Use <boost/stacktrace/frame.hpp> header instead of this one!
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 namespace boost { namespace stacktrace {
 
 /// @class boost::stacktrace::frame boost/stacktrace/detail/frame_decl.hpp <boost/stacktrace/frame.hpp>
@@ -146,7 +156,10 @@ namespace detail {
 
 }} // namespace boost::stacktrace
 
-
 #include <boost/stacktrace/detail/pop_options.h>
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #endif // BOOST_STACKTRACE_DETAIL_FRAME_DECL_HPP
diff --git a/include/boost/stacktrace/detail/frame_msvc.ipp b/include/boost/stacktrace/detail/frame_msvc.ipp
index 4d782761..12f5e09c 100644
--- a/include/boost/stacktrace/detail/frame_msvc.ipp
+++ b/include/boost/stacktrace/detail/frame_msvc.ipp
@@ -12,16 +12,9 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/frame.hpp>
-
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <boost/core/demangle.hpp>
 #include <boost/core/noncopyable.hpp>
-#include <boost/stacktrace/detail/to_dec_array.hpp>
-#include <boost/stacktrace/detail/to_hex_array.hpp>
-
-#ifndef BOOST_STACKTRACE_DISABLE_OFFSET_ADDR_BASE
-#include <boost/stacktrace/detail/addr_base_msvc.hpp>
-#endif
 
 #ifdef WIN32_LEAN_AND_MEAN
 #include <windows.h>
@@ -36,6 +29,16 @@
 #include "dbgeng.h"
 
 #include <mutex>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#include <boost/stacktrace/frame.hpp>
+
+#include <boost/stacktrace/detail/to_dec_array.hpp>
+#include <boost/stacktrace/detail/to_hex_array.hpp>
+
+#ifndef BOOST_STACKTRACE_DISABLE_OFFSET_ADDR_BASE
+#include <boost/stacktrace/detail/addr_base_msvc.hpp>
+#endif
 
 #if defined(__clang__) || defined(BOOST_MSVC)
 #   pragma comment(lib, "ole32.lib")
diff --git a/include/boost/stacktrace/detail/frame_unwind.ipp b/include/boost/stacktrace/detail/frame_unwind.ipp
index 5a7cbea1..40ad842f 100644
--- a/include/boost/stacktrace/detail/frame_unwind.ipp
+++ b/include/boost/stacktrace/detail/frame_unwind.ipp
@@ -12,15 +12,18 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+#include <boost/core/demangle.hpp>
+
+#include <cstdio>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #include <boost/stacktrace/frame.hpp>
 
 #include <boost/stacktrace/detail/to_hex_array.hpp>
 #include <boost/stacktrace/detail/location_from_symbol.hpp>
 #include <boost/stacktrace/detail/to_dec_array.hpp>
 #include <boost/stacktrace/detail/addr_base.hpp>
-#include <boost/core/demangle.hpp>
-
-#include <cstdio>
 
 #ifdef BOOST_STACKTRACE_USE_BACKTRACE
 #   include <boost/stacktrace/detail/libbacktrace_impls.hpp>
diff --git a/include/boost/stacktrace/detail/libbacktrace_impls.hpp b/include/boost/stacktrace/detail/libbacktrace_impls.hpp
index bde53f22..616bd820 100644
--- a/include/boost/stacktrace/detail/libbacktrace_impls.hpp
+++ b/include/boost/stacktrace/detail/libbacktrace_impls.hpp
@@ -12,9 +12,7 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/detail/to_hex_array.hpp>
-#include <boost/stacktrace/detail/to_dec_array.hpp>
-#include <boost/stacktrace/detail/location_from_symbol.hpp>
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <boost/core/demangle.hpp>
 
 #ifdef BOOST_STACKTRACE_BACKTRACE_INCLUDE_FILE
@@ -22,6 +20,11 @@
 #else
 #   include <backtrace.h>
 #endif
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#include <boost/stacktrace/detail/to_hex_array.hpp>
+#include <boost/stacktrace/detail/to_dec_array.hpp>
+#include <boost/stacktrace/detail/location_from_symbol.hpp>
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/location_from_symbol.hpp b/include/boost/stacktrace/detail/location_from_symbol.hpp
index ea88c3e6..9dbd5f6f 100644
--- a/include/boost/stacktrace/detail/location_from_symbol.hpp
+++ b/include/boost/stacktrace/detail/location_from_symbol.hpp
@@ -12,11 +12,13 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
 #   include <dlfcn.h>
 #else
 #   include <boost/winapi/dll.hpp>
 #endif
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #ifdef _AIX
 /* AIX doesn't provide dladdr syscall.
@@ -26,6 +28,7 @@
 
 #include <sys/ldr.h>
 #include <sys/debug.h>
+
 #include <cstring>
 #include <string>
 #include <vector>
diff --git a/include/boost/stacktrace/detail/safe_dump_posix.ipp b/include/boost/stacktrace/detail/safe_dump_posix.ipp
index a5cc86ef..2ff13ac7 100644
--- a/include/boost/stacktrace/detail/safe_dump_posix.ipp
+++ b/include/boost/stacktrace/detail/safe_dump_posix.ipp
@@ -12,12 +12,13 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/safe_dump_to.hpp>
-
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <unistd.h>     // ::write
 #include <fcntl.h>      // ::open
 #include <sys/stat.h>   // S_IWUSR and friends
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
+#include <boost/stacktrace/safe_dump_to.hpp>
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/safe_dump_win.ipp b/include/boost/stacktrace/detail/safe_dump_win.ipp
index 9b998ce0..a8cf6c34 100644
--- a/include/boost/stacktrace/detail/safe_dump_win.ipp
+++ b/include/boost/stacktrace/detail/safe_dump_win.ipp
@@ -12,14 +12,16 @@
 #   pragma once
 #endif
 
-#include <boost/stacktrace/safe_dump_to.hpp>
-
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <boost/core/noncopyable.hpp>
 
 #include <boost/winapi/get_current_process.hpp>
 #include <boost/winapi/file_management.hpp>
 #include <boost/winapi/handles.hpp>
 #include <boost/winapi/access_rights.hpp>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#include <boost/stacktrace/safe_dump_to.hpp>
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/to_dec_array.hpp b/include/boost/stacktrace/detail/to_dec_array.hpp
index dc5372e3..fdba1ba4 100644
--- a/include/boost/stacktrace/detail/to_dec_array.hpp
+++ b/include/boost/stacktrace/detail/to_dec_array.hpp
@@ -12,8 +12,10 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <array>
 #include <cstddef>  // std::size_t
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/to_hex_array.hpp b/include/boost/stacktrace/detail/to_hex_array.hpp
index ee9a6b15..98c54e63 100644
--- a/include/boost/stacktrace/detail/to_hex_array.hpp
+++ b/include/boost/stacktrace/detail/to_hex_array.hpp
@@ -12,8 +12,10 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <array>
 #include <type_traits>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/try_dec_convert.hpp b/include/boost/stacktrace/detail/try_dec_convert.hpp
index 4d5f2478..0f026549 100644
--- a/include/boost/stacktrace/detail/try_dec_convert.hpp
+++ b/include/boost/stacktrace/detail/try_dec_convert.hpp
@@ -12,7 +12,9 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <cstdlib>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 namespace boost { namespace stacktrace { namespace detail {
 
diff --git a/include/boost/stacktrace/detail/void_ptr_cast.hpp b/include/boost/stacktrace/detail/void_ptr_cast.hpp
index f275ecfb..9e83e9be 100644
--- a/include/boost/stacktrace/detail/void_ptr_cast.hpp
+++ b/include/boost/stacktrace/detail/void_ptr_cast.hpp
@@ -13,7 +13,9 @@
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <type_traits>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #if defined(__GNUC__) && defined(__GNUC_MINOR__) && (__GNUC__ * 100 + __GNUC_MINOR__ > 301)
 #   pragma GCC system_header
@@ -22,7 +24,7 @@
 namespace boost { namespace stacktrace { namespace detail {
 
 // GCC warns when reinterpret_cast between function pointer and object pointer occur.
-// This functionsuppress the warnings and ensures that such casts are safe.
+// This function suppress the warnings and ensures that such casts are safe.
 template <class To, class From>
 To void_ptr_cast(From* v) noexcept {
     static_assert(
diff --git a/include/boost/stacktrace/frame.hpp b/include/boost/stacktrace/frame.hpp
index d14f8e7d..734eed81 100644
--- a/include/boost/stacktrace/frame.hpp
+++ b/include/boost/stacktrace/frame.hpp
@@ -7,13 +7,18 @@
 #ifndef BOOST_STACKTRACE_FRAME_HPP
 #define BOOST_STACKTRACE_FRAME_HPP
 
-#include <boost/config.hpp>
+#include <boost/stacktrace/detail/backend_config.hpp>
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <iosfwd>
 #include <string>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #include <boost/stacktrace/detail/frame_decl.hpp>
 #include <boost/stacktrace/detail/push_options.h>
@@ -32,6 +37,8 @@ void* boost_stacktrace_impl_return_nullptr() { return nullptr; }
 }
 #endif
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 namespace boost { namespace stacktrace {
 
 /// Comparison operators that provide platform dependant ordering and have O(1) complexity; are Async-Handler-Safe.
@@ -58,6 +65,8 @@ std::basic_ostream<CharT, TraitsT>& operator<<(std::basic_ostream<CharT, TraitsT
 
 }} // namespace boost::stacktrace
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
 /// @cond
 
 #include <boost/stacktrace/detail/pop_options.h>
@@ -73,5 +82,6 @@ std::basic_ostream<CharT, TraitsT>& operator<<(std::basic_ostream<CharT, TraitsT
 #endif
 /// @endcond
 
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #endif // BOOST_STACKTRACE_FRAME_HPP
diff --git a/include/boost/stacktrace/safe_dump_to.hpp b/include/boost/stacktrace/safe_dump_to.hpp
index 474d6619..42c28237 100644
--- a/include/boost/stacktrace/safe_dump_to.hpp
+++ b/include/boost/stacktrace/safe_dump_to.hpp
@@ -7,16 +7,25 @@
 #ifndef BOOST_STACKTRACE_SAFE_DUMP_TO_HPP
 #define BOOST_STACKTRACE_SAFE_DUMP_TO_HPP
 
-#include <boost/config.hpp>
+#include <boost/stacktrace/detail/config.hpp>
+
+#if defined(BOOST_USE_MODULES) && !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+    import boost.stacktrace.dump;
+#endif
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <cstddef>
 
 #if defined(BOOST_WINDOWS)
 #include <boost/winapi/config.hpp>
 #endif
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #include <boost/stacktrace/detail/push_options.h>
 
@@ -35,7 +44,9 @@ namespace boost { namespace stacktrace {
 /// @cond
 namespace detail {
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
     using native_frame_ptr_t = const void*;
+BOOST_STACKTRACE_END_MODULE_EXPORT
     enum helper{ max_frames_dump = 128 };
 
     BOOST_STACKTRACE_FUNCTION std::size_t from_dump(const char* filename, native_frame_ptr_t* out_frames);
@@ -48,6 +59,8 @@ namespace detail {
 #endif
 
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 struct this_thread_frames { // struct is required to avoid warning about usage of inline+BOOST_NOINLINE
     BOOST_NOINLINE BOOST_STACKTRACE_FUNCTION static std::size_t collect(native_frame_ptr_t* out_frames, std::size_t max_frames_count, std::size_t skip) noexcept;
 
@@ -79,9 +92,13 @@ struct this_thread_frames { // struct is required to avoid warning about usage o
     }
 };
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
 } // namespace detail
 /// @endcond
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 /// @brief Stores current function call sequence into the memory.
 ///
 /// @b Complexity: O(N) where N is call sequence length, O(1) if BOOST_STACKTRACE_USE_NOOP is defined.
@@ -199,6 +216,8 @@ BOOST_FORCEINLINE std::size_t safe_dump_to(std::size_t skip, std::size_t max_dep
 
 }} // namespace boost::stacktrace
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
 #ifdef BOOST_INTEL
 #   pragma warning(pop)
 #endif
@@ -223,4 +242,6 @@ BOOST_FORCEINLINE std::size_t safe_dump_to(std::size_t skip, std::size_t max_dep
 #   endif
 #endif
 
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #endif // BOOST_STACKTRACE_SAFE_DUMP_TO_HPP
diff --git a/include/boost/stacktrace/stacktrace.hpp b/include/boost/stacktrace/stacktrace.hpp
index f0000dd5..6070a405 100644
--- a/include/boost/stacktrace/stacktrace.hpp
+++ b/include/boost/stacktrace/stacktrace.hpp
@@ -7,11 +7,15 @@
 #ifndef BOOST_STACKTRACE_STACKTRACE_HPP
 #define BOOST_STACKTRACE_STACKTRACE_HPP
 
-#include <boost/config.hpp>
+#include <boost/stacktrace/detail/backend_config.hpp>
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
 
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <boost/core/no_exceptions_support.hpp>
 #include <boost/container_hash/hash_fwd.hpp>
 
@@ -22,9 +26,9 @@
 #ifndef BOOST_NO_CXX11_HDR_TYPE_TRAITS
 #   include <type_traits>
 #endif
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #include <boost/stacktrace/stacktrace_fwd.hpp>
-#include <boost/stacktrace/safe_dump_to.hpp>
 #include <boost/stacktrace/detail/frame_decl.hpp>
 #include <boost/stacktrace/frame.hpp>
 
@@ -58,9 +62,15 @@ namespace impl {
 
 #if defined(__GNUC__) && defined(__ELF__)
 
+#if defined(BOOST_USE_MODULES)
+extern "C++"
+#endif
 BOOST_NOINLINE BOOST_SYMBOL_VISIBLE __attribute__((weak))
 const char* current_exception_stacktrace() noexcept;
 
+#if defined(BOOST_USE_MODULES)
+extern "C++"
+#endif
 BOOST_NOINLINE BOOST_SYMBOL_VISIBLE __attribute__((weak))
 bool& ref_capture_stacktraces_at_throw() noexcept;
 
@@ -68,6 +78,8 @@ bool& ref_capture_stacktraces_at_throw() noexcept;
 
 } // namespace impl
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 /// Class that on construction copies minimal information about call stack into its internals and provides access to that information.
 /// @tparam Allocator Allocator to use during stack capture.
 template <class Allocator>
@@ -482,10 +494,14 @@ std::basic_ostream<CharT, TraitsT>& operator<<(std::basic_ostream<CharT, TraitsT
 /// This is the typedef to use unless you'd like to provide a specific allocator to boost::stacktrace::basic_stacktrace.
 typedef basic_stacktrace<> stacktrace;
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
 }} // namespace boost::stacktrace
 
 #ifdef BOOST_INTEL
 #   pragma warning(pop)
 #endif
 
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #endif // BOOST_STACKTRACE_STACKTRACE_HPP
diff --git a/include/boost/stacktrace/stacktrace_fwd.hpp b/include/boost/stacktrace/stacktrace_fwd.hpp
index 6b0ee28d..764591b7 100644
--- a/include/boost/stacktrace/stacktrace_fwd.hpp
+++ b/include/boost/stacktrace/stacktrace_fwd.hpp
@@ -7,13 +7,21 @@
 #ifndef BOOST_STACKTRACE_STACKTRACE_FWD_HPP
 #define BOOST_STACKTRACE_STACKTRACE_FWD_HPP
 
+#include <boost/stacktrace/detail/backend_config.hpp>
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
+#if !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 #include <cstddef>
 #include <memory>
+#endif // !defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 /// @file stacktrace_fwd.hpp This header contains only forward declarations of
 /// boost::stacktrace::frame, boost::stacktrace::basic_stacktrace, boost::stacktrace::stacktrace
 /// and does not include any other Boost headers.
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 /// @cond
 namespace boost { namespace stacktrace {
 
@@ -24,5 +32,8 @@ typedef basic_stacktrace<> stacktrace;
 }} // namespace boost::stacktrace
 /// @endcond
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
 
 #endif // BOOST_STACKTRACE_STACKTRACE_FWD_HPP
diff --git a/include/boost/stacktrace/this_thread.hpp b/include/boost/stacktrace/this_thread.hpp
index 6b4f9daa..29dbc4ce 100644
--- a/include/boost/stacktrace/this_thread.hpp
+++ b/include/boost/stacktrace/this_thread.hpp
@@ -7,13 +7,18 @@
 #ifndef BOOST_STACKTRACE_THIS_THREAD_HPP
 #define BOOST_STACKTRACE_THIS_THREAD_HPP
 
-#include <boost/config.hpp>
+#include <boost/stacktrace/detail/backend_config.hpp>
+
+#if !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
 
 #include <boost/stacktrace/stacktrace.hpp>
 
+BOOST_STACKTRACE_BEGIN_MODULE_EXPORT
+
 namespace boost { namespace stacktrace { namespace this_thread {
 
 /// @brief Invoking the function with the enable parameter equal to `true`
@@ -59,4 +64,8 @@ inline bool get_capture_stacktraces_at_throw() noexcept {
 
 }}} // namespace boost::stacktrace::this_thread
 
+BOOST_STACKTRACE_END_MODULE_EXPORT
+
+#endif // !defined(BOOST_USE_MODULES) || defined(BOOST_STACKTRACE_INTERFACE_UNIT)
+
 #endif // BOOST_STACKTRACE_THIS_THREAD_HPP
diff --git a/modules/boost_stacktrace.cppm b/modules/boost_stacktrace.cppm
new file mode 100644
index 00000000..35cfe4b1
--- /dev/null
+++ b/modules/boost_stacktrace.cppm
@@ -0,0 +1,9 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+export module boost.stacktrace;
+export import boost.stacktrace.BOOST_STACKTRACE_BACKEND_MODULE;
diff --git a/modules/boost_stacktrace_addr2line.cppm b/modules/boost_stacktrace_addr2line.cppm
new file mode 100644
index 00000000..c331c9c6
--- /dev/null
+++ b/modules/boost_stacktrace_addr2line.cppm
@@ -0,0 +1,49 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#ifndef _GNU_SOURCE
+#   define _GNU_SOURCE
+#endif
+
+#include <boost/config.hpp>
+#include <boost/core/no_exceptions_support.hpp>
+#include <boost/core/demangle.hpp>
+#include <boost/core/noncopyable.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/predef.h>
+
+#include <vector>
+#include <fstream>
+#include <sstream>
+#include <cxxabi.h>
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+
+#include <dlfcn.h>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.addr2line;
+
+import boost.stacktrace.dump;
+
+#ifdef __clang__
+#   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#endif
+
+#include <boost/stacktrace/stacktrace.hpp>
+#include <boost/stacktrace/this_thread.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#define BOOST_STACKTRACE_USE_ADDR2LINE
+#include <boost/stacktrace/detail/frame_unwind.ipp>
diff --git a/modules/boost_stacktrace_backtrace.cppm b/modules/boost_stacktrace_backtrace.cppm
new file mode 100644
index 00000000..ae95d564
--- /dev/null
+++ b/modules/boost_stacktrace_backtrace.cppm
@@ -0,0 +1,47 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#ifndef _GNU_SOURCE
+#   define _GNU_SOURCE
+#endif
+
+#include <boost/config.hpp>
+#include <boost/core/no_exceptions_support.hpp>
+#include <boost/core/demangle.hpp>
+#include <boost/core/noncopyable.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/predef.h>
+
+#include <backtrace.h>
+
+#include <vector>
+#include <fstream>
+#include <sstream>
+#include <cxxabi.h>
+
+#include <dlfcn.h>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.backtrace;
+
+import boost.stacktrace.dump;
+
+#ifdef __clang__
+#   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#endif
+
+#include <boost/stacktrace/stacktrace.hpp>
+#include <boost/stacktrace/this_thread.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#define BOOST_STACKTRACE_USE_BACKTRACE
+#include <boost/stacktrace/detail/frame_unwind.ipp>
diff --git a/modules/boost_stacktrace_basic.cppm b/modules/boost_stacktrace_basic.cppm
new file mode 100644
index 00000000..ae3a22e1
--- /dev/null
+++ b/modules/boost_stacktrace_basic.cppm
@@ -0,0 +1,44 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#ifndef _GNU_SOURCE
+#   define _GNU_SOURCE
+#endif
+
+#include <boost/config.hpp>
+#include <boost/core/no_exceptions_support.hpp>
+#include <boost/core/demangle.hpp>
+#include <boost/core/noncopyable.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/predef.h>
+
+#include <vector>
+#include <fstream>
+#include <sstream>
+#include <cxxabi.h>
+
+#include <dlfcn.h>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.basic;
+
+import boost.stacktrace.dump;
+
+#ifdef __clang__
+#   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#endif
+
+#include <boost/stacktrace/stacktrace.hpp>
+#include <boost/stacktrace/this_thread.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#include <boost/stacktrace/detail/frame_unwind.ipp>
diff --git a/modules/boost_stacktrace_dump.cppm b/modules/boost_stacktrace_dump.cppm
new file mode 100644
index 00000000..b9762769
--- /dev/null
+++ b/modules/boost_stacktrace_dump.cppm
@@ -0,0 +1,45 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#ifndef _GNU_SOURCE
+#   define _GNU_SOURCE
+#endif
+
+#include <boost/config.hpp>
+#include <boost/predef.h>
+
+#include <fcntl.h>
+#include <unwind.h>
+#include <stdio.h>
+#include <sys/stat.h>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.dump;
+
+#ifdef __clang__
+#   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#endif
+
+#include <boost/stacktrace/safe_dump_to.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#if defined(BOOST_WINDOWS)
+#    include <boost/stacktrace/detail/safe_dump_win.ipp>
+#else
+#    include <boost/stacktrace/detail/safe_dump_posix.ipp>
+#endif
+#if defined(BOOST_WINDOWS) && !defined(BOOST_WINAPI_IS_MINGW) // MinGW does not provide RtlCaptureStackBackTrace. MinGW-w64 does.
+#    include <boost/stacktrace/detail/collect_msvc.ipp>
+#else
+#    include <boost/stacktrace/detail/collect_unwind.ipp>
+#endif
+
diff --git a/modules/boost_stacktrace_noop.cppm b/modules/boost_stacktrace_noop.cppm
new file mode 100644
index 00000000..80ef6f06
--- /dev/null
+++ b/modules/boost_stacktrace_noop.cppm
@@ -0,0 +1,33 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#include <boost/config.hpp>
+#include <boost/core/no_exceptions_support.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
+
+#include <vector>
+#include <memory>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.noop;
+
+#ifdef __clang__
+#   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
+#endif
+
+#include <boost/stacktrace/safe_dump_to.hpp>
+#include <boost/stacktrace/stacktrace.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#include <boost/stacktrace/detail/frame_noop.ipp>
+#include <boost/stacktrace/detail/safe_dump_noop.ipp>
+#include <boost/stacktrace/detail/collect_noop.ipp>
diff --git a/modules/boost_stacktrace_windbg.cppm b/modules/boost_stacktrace_windbg.cppm
new file mode 100644
index 00000000..af537442
--- /dev/null
+++ b/modules/boost_stacktrace_windbg.cppm
@@ -0,0 +1,29 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#include <boost/config.hpp>
+#include <boost/core/no_exceptions_support.hpp>
+#include <boost/core/demangle.hpp>
+#include <boost/core/noncopyable.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/predef.h>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.windbg;
+
+import boost.stacktrace.dump;
+
+#include <boost/stacktrace/stacktrace.hpp>
+#include <boost/stacktrace/this_thread.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#include <boost/stacktrace/detail/frame_msvc.ipp>
diff --git a/modules/boost_stacktrace_windbg_cached.cppm b/modules/boost_stacktrace_windbg_cached.cppm
new file mode 100644
index 00000000..fb374a2e
--- /dev/null
+++ b/modules/boost_stacktrace_windbg_cached.cppm
@@ -0,0 +1,30 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+module;
+
+#include <boost/config.hpp>
+#include <boost/core/no_exceptions_support.hpp>
+#include <boost/core/demangle.hpp>
+#include <boost/core/noncopyable.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/predef.h>
+
+#define BOOST_STACKTRACE_INTERFACE_UNIT
+#define BOOST_STACKTRACE_LINK
+
+export module boost.stacktrace.windbg;
+
+import boost.stacktrace.dump;
+
+#include <boost/stacktrace/stacktrace.hpp>
+#include <boost/stacktrace/this_thread.hpp>
+
+module :private;
+#define BOOST_STACKTRACE_INTERNAL_BUILD_LIBS
+#define BOOST_STACKTRACE_USE_WINDBG_CACHED
+#include <boost/stacktrace/detail/frame_msvc.ipp>
diff --git a/modules/samples/usage_sample.cpp b/modules/samples/usage_sample.cpp
new file mode 100644
index 00000000..d3ef2bee
--- /dev/null
+++ b/modules/samples/usage_sample.cpp
@@ -0,0 +1,34 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+#include <iostream>
+#include <boost/config.hpp>
+
+#if defined(STACKTRACE_MODULE)
+import STACKTRACE_MODULE;
+#else
+import boost.stacktrace;
+#endif
+
+namespace {
+
+BOOST_NOINLINE void foo() {
+    auto trace = boost::stacktrace::stacktrace{};
+    std::cerr << trace;
+}
+
+BOOST_NOINLINE void bar() {
+    foo();
+}
+
+}
+
+int main() {
+    bar();
+
+    return 0;
+}
diff --git a/modules/samples/usage_sample_from_exception.cpp b/modules/samples/usage_sample_from_exception.cpp
new file mode 100644
index 00000000..5cac1f2a
--- /dev/null
+++ b/modules/samples/usage_sample_from_exception.cpp
@@ -0,0 +1,34 @@
+// Copyright Antony Polukhin, 2025-2026.
+// Copyright Fedor Osetrov, 2025-2026.
+//
+// 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)
+
+#include <iostream>
+#include <stdexcept>
+
+#include <boost/config.hpp>
+
+#include <boost/stacktrace.hpp>
+
+namespace {
+
+BOOST_NOINLINE void foo() {
+    throw std::logic_error{"Foo"};
+}
+
+BOOST_NOINLINE void bar() {
+    foo();
+}
+
+}
+
+int main() {
+    try {
+        bar();
+    } catch (const std::exception& ex) {
+        const auto trace = boost::stacktrace::stacktrace::from_current_exception();
+        std::cerr << "Exception: " << ex.what() << ", trace:\n" << trace << '\n';
+    }
+}
diff --git a/test/cmake_subdir_test/CMakeLists.txt b/test/cmake_subdir_test/CMakeLists.txt
index b852a471..049a5572 100644
--- a/test/cmake_subdir_test/CMakeLists.txt
+++ b/test/cmake_subdir_test/CMakeLists.txt
@@ -40,13 +40,39 @@ endforeach()
 enable_testing()
 add_subdirectory(../.. boostorg/stacktrace)
 
-add_executable(main main.cpp)
-target_link_libraries(main Boost::stacktrace)
-
-add_executable(main_header_only main.cpp)
-target_include_directories(main_header_only PRIVATE ../../include)
-target_compile_definitions(main_header_only PRIVATE "_GNU_SOURCE=1")
-target_link_libraries(main_header_only PRIVATE Boost::core Boost::container_hash Boost::predef Boost::winapi)
-
-add_test(NAME main COMMAND main)
-add_test(NAME main_header_only COMMAND main_header_only)
+add_executable(stacktrace_main main.cpp)
+target_link_libraries(stacktrace_main Boost::stacktrace)
+
+add_executable(stacktrace_main_header_only main.cpp)
+target_include_directories(stacktrace_main_header_only PRIVATE ../../include)
+target_compile_definitions(stacktrace_main_header_only PRIVATE "_GNU_SOURCE=1")
+target_link_libraries(stacktrace_main_header_only PRIVATE Boost::core Boost::container_hash Boost::predef Boost::winapi)
+
+add_test(NAME stacktrace_main COMMAND stacktrace_main)
+add_test(NAME stacktrace_main_header_only COMMAND stacktrace_main_header_only)
+
+if (BOOST_USE_MODULES)
+    add_executable(boost_stacktrace_module_usage ../../modules/samples/usage_sample.cpp)
+    target_link_libraries(boost_stacktrace_module_usage PRIVATE Boost::stacktrace)
+    add_test(NAME boost_stacktrace_module_usage COMMAND boost_stacktrace_module_usage)
+
+    add_executable(boost_stacktrace_from_exception_module_usage ../../modules/samples/usage_sample_from_exception.cpp)
+    target_link_libraries(boost_stacktrace_from_exception_module_usage PRIVATE Boost::stacktrace Boost::stacktrace_from_exception)
+    add_test(NAME boost_stacktrace_from_exception_module_usage COMMAND boost_stacktrace_from_exception_module_usage)
+
+    foreach(backend noop basic addr2line backtrace)
+      if (NOT TARGET Boost::stacktrace_${backend})
+        message(STATUS "Skipping ${backend} backend")
+        continue()
+      endif()
+      add_executable(boost_stacktrace_module_usage_${backend} ../../modules/samples/usage_sample.cpp)
+      target_link_libraries(boost_stacktrace_module_usage_${backend} PRIVATE Boost::stacktrace_${backend})
+      target_compile_definitions(boost_stacktrace_module_usage_${backend} PRIVATE STACKTRACE_MODULE=boost.stacktrace.${backend})
+      add_test(NAME boost_stacktrace_module_usage_${backend} COMMAND boost_stacktrace_module_usage_${backend})
+
+      add_executable(boost_stacktrace_from_exception_module_usage_${backend} ../../modules/samples/usage_sample_from_exception.cpp)
+      target_link_libraries(boost_stacktrace_from_exception_module_usage_${backend} PRIVATE Boost::stacktrace_${backend} Boost::stacktrace_from_exception)
+      target_compile_definitions(boost_stacktrace_from_exception_module_usage_${backend} PRIVATE STACKTRACE_MODULE=boost.stacktrace.${backend})
+      add_test(NAME boost_stacktrace_from_exception_module_usage_${backend} COMMAND boost_stacktrace_from_exception_module_usage_${backend})
+    endforeach()
+endif()
diff --git a/test/cmake_subdir_test/main.cpp b/test/cmake_subdir_test/main.cpp
index 28a59714..3bb5024c 100644
--- a/test/cmake_subdir_test/main.cpp
+++ b/test/cmake_subdir_test/main.cpp
@@ -3,8 +3,8 @@
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
-#include <boost/stacktrace/stacktrace.hpp>
 #include <iostream>
+#include <boost/stacktrace/stacktrace.hpp>
 
 int main()
 {
diff --git a/test/test.cpp b/test/test.cpp
index ff8c0a84..8333c0d1 100644
--- a/test/test.cpp
+++ b/test/test.cpp
@@ -4,9 +4,6 @@
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 
-#include <boost/stacktrace/stacktrace_fwd.hpp>
-
-#include <boost/stacktrace.hpp>
 #include <fstream>
 #include <iostream>
 #include <sstream>
@@ -18,6 +15,8 @@
 
 #include "test_impl.hpp"
 
+#include <boost/stacktrace.hpp>
+
 using boost::stacktrace::stacktrace;
 using boost::stacktrace::frame;
 
diff --git a/test/test_from_exception.cpp b/test/test_from_exception.cpp
index db5b36eb..47aad23f 100644
--- a/test/test_from_exception.cpp
+++ b/test/test_from_exception.cpp
@@ -4,13 +4,13 @@
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 
-#include <boost/stacktrace.hpp>
-
 #include <iostream>
 #include <thread>
 
 #include <boost/core/lightweight_test.hpp>
 
+#include <boost/stacktrace.hpp>
+
 namespace boost { namespace stacktrace { namespace impl {
   void assert_no_pending_traces() noexcept;
 }}}
diff --git a/test/test_from_exception_none.cpp b/test/test_from_exception_none.cpp
index a9762634..e3c4a4e5 100644
--- a/test/test_from_exception_none.cpp
+++ b/test/test_from_exception_none.cpp
@@ -4,10 +4,10 @@
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 
-#include <boost/stacktrace.hpp>
-
 #include <boost/core/lightweight_test.hpp>
 
+#include <boost/stacktrace.hpp>
+
 using boost::stacktrace::stacktrace;
 
 
diff --git a/test/test_torture.cpp b/test/test_torture.cpp
index 2df475de..2008b2dc 100644
--- a/test/test_torture.cpp
+++ b/test/test_torture.cpp
@@ -11,8 +11,8 @@
 // test and `top` does.
 
 
-#include <boost/stacktrace.hpp>
 #include <iostream>
+#include <boost/stacktrace.hpp>
 
 #include "test_impl.hpp"
 
diff --git a/test/test_trivial.cpp b/test/test_trivial.cpp
index be21cc4b..98c6bd14 100644
--- a/test/test_trivial.cpp
+++ b/test/test_trivial.cpp
@@ -6,10 +6,10 @@
 
 // See https://github.com/boostorg/stacktrace/issues/116
 
-#include <boost/stacktrace/stacktrace.hpp>
-
 #include <iostream>
 
+#include <boost/stacktrace/stacktrace.hpp>
+
 int main() {
   std::cout << boost::stacktrace::stacktrace() << std::endl;
 }
diff --git a/test/test_void_ptr_cast.cpp b/test/test_void_ptr_cast.cpp
index 5e569649..8d28d78e 100644
--- a/test/test_void_ptr_cast.cpp
+++ b/test/test_void_ptr_cast.cpp
@@ -4,10 +4,10 @@
 // (See accompanying file LICENSE_1_0.txt
 // or copy at http://www.boost.org/LICENSE_1_0.txt)
 
-#include <boost/stacktrace/detail/void_ptr_cast.hpp>
-
 #include <boost/core/lightweight_test.hpp>
 
+#include <boost/stacktrace/detail/void_ptr_cast.hpp>
+
 int foo1_func(int) { return 0; }
 void foo2_func(int, int, ...) {}
 

From 28ea4a11387185cd57957328c879c55f2901af03 Mon Sep 17 00:00:00 2001
From: Fedor Osetrov <fiosetrova@gmail.com>
Date: Sat, 9 May 2026 07:48:50 +0000
Subject: [PATCH 9/9] fix build

---
 CMakeLists.txt                                  | 3 +++
 modules/boost_stacktrace_addr2line.cppm         | 9 ---------
 modules/boost_stacktrace_backtrace.cppm         | 9 ---------
 modules/boost_stacktrace_basic.cppm             | 9 ---------
 modules/boost_stacktrace_dump.cppm              | 9 ---------
 modules/boost_stacktrace_noop.cppm              | 8 --------
 modules/samples/usage_sample_from_exception.cpp | 8 --------
 7 files changed, 3 insertions(+), 52 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 87318c80..c753f23f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -136,6 +136,9 @@ else()
 endif()
 
 if(BOOST_USE_MODULES)
+  if(NOT CMAKE_CXX_STANDARD)
+    set(CMAKE_CXX_STANDARD 20)
+  endif()
   if ((CMAKE_CXX_STANDARD IN_LIST CMAKE_CXX_COMPILER_IMPORT_STD) AND CMAKE_CXX_MODULE_STD)
     message(STATUS "Using `import std;`")
     set(__import_std ON)
diff --git a/modules/boost_stacktrace_addr2line.cppm b/modules/boost_stacktrace_addr2line.cppm
index 310948d9..b8dee270 100644
--- a/modules/boost_stacktrace_addr2line.cppm
+++ b/modules/boost_stacktrace_addr2line.cppm
@@ -18,18 +18,12 @@ module;
 #include <boost/container_hash/hash_fwd.hpp>
 #include <boost/predef.h>
 
-<<<<<<< HEAD
 #if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
-=======
->>>>>>> develop
 #include <vector>
 #include <fstream>
 #include <sstream>
 #include <cxxabi.h>
-<<<<<<< HEAD
 #endif
-=======
->>>>>>> develop
 
 #include <sys/types.h>
 #include <sys/wait.h>
@@ -42,13 +36,10 @@ module;
 
 export module boost.stacktrace.addr2line;
 
-<<<<<<< HEAD
 #if defined(BOOST_STACKTRACE_USE_STD_MODULE)
 import std;
 #endif
 
-=======
->>>>>>> develop
 import boost.stacktrace.dump;
 
 #ifdef __clang__
diff --git a/modules/boost_stacktrace_backtrace.cppm b/modules/boost_stacktrace_backtrace.cppm
index 9f5c31b8..9860c200 100644
--- a/modules/boost_stacktrace_backtrace.cppm
+++ b/modules/boost_stacktrace_backtrace.cppm
@@ -20,18 +20,12 @@ module;
 
 #include <backtrace.h>
 
-<<<<<<< HEAD
 #if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
-=======
->>>>>>> develop
 #include <vector>
 #include <fstream>
 #include <sstream>
 #include <cxxabi.h>
-<<<<<<< HEAD
 #endif
-=======
->>>>>>> develop
 
 #include <dlfcn.h>
 
@@ -40,13 +34,10 @@ module;
 
 export module boost.stacktrace.backtrace;
 
-<<<<<<< HEAD
 #if defined(BOOST_STACKTRACE_USE_STD_MODULE)
 import std;
 #endif
 
-=======
->>>>>>> develop
 import boost.stacktrace.dump;
 
 #ifdef __clang__
diff --git a/modules/boost_stacktrace_basic.cppm b/modules/boost_stacktrace_basic.cppm
index 98044c6b..15985c92 100644
--- a/modules/boost_stacktrace_basic.cppm
+++ b/modules/boost_stacktrace_basic.cppm
@@ -18,18 +18,12 @@ module;
 #include <boost/container_hash/hash_fwd.hpp>
 #include <boost/predef.h>
 
-<<<<<<< HEAD
 #if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
-=======
->>>>>>> develop
 #include <vector>
 #include <fstream>
 #include <sstream>
 #include <cxxabi.h>
-<<<<<<< HEAD
 #endif
-=======
->>>>>>> develop
 
 #include <dlfcn.h>
 
@@ -38,13 +32,10 @@ module;
 
 export module boost.stacktrace.basic;
 
-<<<<<<< HEAD
 #if defined(BOOST_STACKTRACE_USE_STD_MODULE)
 import std;
 #endif
 
-=======
->>>>>>> develop
 import boost.stacktrace.dump;
 
 #ifdef __clang__
diff --git a/modules/boost_stacktrace_dump.cppm b/modules/boost_stacktrace_dump.cppm
index 48cea357..b1fb6d8d 100644
--- a/modules/boost_stacktrace_dump.cppm
+++ b/modules/boost_stacktrace_dump.cppm
@@ -14,18 +14,12 @@ module;
 #include <boost/config.hpp>
 #include <boost/predef.h>
 
-<<<<<<< HEAD
 #if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <stdio.h>
 #endif
 
 #include <fcntl.h>
 #include <unwind.h>
-=======
-#include <fcntl.h>
-#include <unwind.h>
-#include <stdio.h>
->>>>>>> develop
 #include <sys/stat.h>
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
@@ -33,13 +27,10 @@ module;
 
 export module boost.stacktrace.dump;
 
-<<<<<<< HEAD
 #if defined(BOOST_STACKTRACE_USE_STD_MODULE)
 import std;
 #endif
 
-=======
->>>>>>> develop
 #ifdef __clang__
 #   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
 #endif
diff --git a/modules/boost_stacktrace_noop.cppm b/modules/boost_stacktrace_noop.cppm
index cf4acfb8..789fe4bd 100644
--- a/modules/boost_stacktrace_noop.cppm
+++ b/modules/boost_stacktrace_noop.cppm
@@ -11,28 +11,20 @@ module;
 #include <boost/core/no_exceptions_support.hpp>
 #include <boost/container_hash/hash_fwd.hpp>
 
-<<<<<<< HEAD
 #if !defined(BOOST_STACKTRACE_USE_STD_MODULE)
 #include <vector>
 #include <memory>
 #endif
-=======
-#include <vector>
-#include <memory>
->>>>>>> develop
 
 #define BOOST_STACKTRACE_INTERFACE_UNIT
 #define BOOST_STACKTRACE_LINK
 
 export module boost.stacktrace.noop;
 
-<<<<<<< HEAD
 #if defined(BOOST_STACKTRACE_USE_STD_MODULE)
 import std;
 #endif
 
-=======
->>>>>>> develop
 #ifdef __clang__
 #   pragma clang diagnostic ignored "-Winclude-angled-in-module-purview"
 #endif
diff --git a/modules/samples/usage_sample_from_exception.cpp b/modules/samples/usage_sample_from_exception.cpp
index 5a11a078..832e8796 100644
--- a/modules/samples/usage_sample_from_exception.cpp
+++ b/modules/samples/usage_sample_from_exception.cpp
@@ -6,11 +6,7 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #include <iostream>
-<<<<<<< HEAD
 #include <map>
-=======
-#include <stdexcept>
->>>>>>> develop
 
 #include <boost/config.hpp>
 
@@ -19,12 +15,8 @@
 namespace {
 
 BOOST_NOINLINE void foo() {
-<<<<<<< HEAD
     std::map<int, int> m;
     std::ignore = m.at(1);
-=======
-    throw std::logic_error{"Foo"};
->>>>>>> develop
 }
 
 BOOST_NOINLINE void bar() {