diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8df9107..b912a5f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -5,26 +5,11 @@ project(tl-expected
   VERSION 1.0.0
   LANGUAGES CXX)
 
-include(CMakePackageConfigHelpers)
-include(CMakeDependentOption)
-include(GNUInstallDirs)
-include(FetchContent)
-include(CTest)
 
 if (NOT DEFINED CMAKE_CXX_STANDARD)
   set(CMAKE_CXX_STANDARD 14)
 endif()
 
-option(EXPECTED_BUILD_PACKAGE "Build package files as well" ON)
-
-cmake_dependent_option(EXPECTED_BUILD_TESTS
-  "Enable tl::expected tests" ON
-  "BUILD_TESTING" OFF)
-
-cmake_dependent_option(EXPECTED_BUILD_PACKAGE_DEB
-  "Create a DEB" ON
-  "EXPECTED_BUILD_PACKAGE" OFF)
-
 add_library(expected INTERFACE)
 target_include_directories(expected
   INTERFACE
@@ -35,83 +20,102 @@ if (NOT CMAKE_SOURCE_DIR STREQUAL PROJECT_SOURCE_DIR)
   add_library(tl::expected ALIAS expected)
 endif()
 
-# Installation help
-configure_package_config_file(
-  "${PROJECT_SOURCE_DIR}/cmake/${PROJECT_NAME}-config.cmake.in"
-  "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
-  INSTALL_DESTINATION "share/cmake/${PROJECT_NAME}")
-
-write_basic_package_version_file(
-  "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config-version.cmake"
-  COMPATIBILITY SameMajorVersion
-  ARCH_INDEPENDENT)
-
-install(TARGETS expected
-  EXPORT ${PROJECT_NAME}-targets
-  INCLUDES DESTINATION "${CMAKE_INSTALL_DATADIR}")
-
-install(EXPORT ${PROJECT_NAME}-targets
-  DESTINATION "${CMAKE_INSTALL_DATADIR}/cmake/${PROJECT_NAME}"
-  NAMESPACE tl::
-  FILE "${PROJECT_NAME}-targets.cmake")
-
-install(FILES
-  "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config-version.cmake"
-  "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
-  DESTINATION "${CMAKE_INSTALL_DATADIR}/cmake/${PROJECT_NAME}")
-
-install(DIRECTORY "include/" TYPE INCLUDE)
-
-if(EXPECTED_BUILD_TESTS)
-  set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
-  set(CATCH_INSTALL_HELPERS OFF)
-  set(CATCH_BUILD_TESTING OFF)
-  set(CATCH_INSTALL_DOCS OFF)
-  FetchContent_Declare(Catch2 URL
-    https://github.com/catchorg/Catch2/archive/v2.9.2.zip) 
-  FetchContent_MakeAvailable(Catch2)
-
-  file(GLOB test-sources CONFIGURE_DEPENDS tests/*.cpp)
-  list(FILTER test-sources EXCLUDE REGEX "tests/test.cpp")
-  add_executable(${PROJECT_NAME}-tests "${test-sources}")
-  target_compile_options(${PROJECT_NAME}-tests PRIVATE
-    $<$<NOT:$<CXX_COMPILER_ID:MSVC>>:-Wall -Wextra>)
-
-  target_link_libraries(${PROJECT_NAME}-tests
-    PRIVATE
-      Catch2::Catch2
-      expected)
-  add_test(NAME tl::expected::tests COMMAND ${PROJECT_NAME}-tests)
-endif()
+if(CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
+  # Project is configured as root (not subdirectory) -> include tests and packaging
+  include(CMakePackageConfigHelpers)
+  include(CMakeDependentOption)
+  include(GNUInstallDirs)
+  include(FetchContent)
+  include(CTest)
 
-if (NOT EXPECTED_BUILD_PACKAGE)
-  return()
-endif()
+  option(EXPECTED_BUILD_PACKAGE "Build package files as well" ON)
 
-list(APPEND source-generators TBZ2 TGZ TXZ ZIP)
+  cmake_dependent_option(EXPECTED_BUILD_TESTS
+    "Enable tl::expected tests" ON
+    "BUILD_TESTING" OFF)
 
-if (CMAKE_HOST_WIN32)
-  list(APPEND binary-generators "WIX")
-endif()
+  cmake_dependent_option(EXPECTED_BUILD_PACKAGE_DEB
+    "Create a DEB" ON
+    "EXPECTED_BUILD_PACKAGE" OFF)
 
-if (EXPECTED_BUILD_PACKAGE_DEB)
-  list(APPEND binary-generators "DEB")
-endif()
+  # Installation help
+  configure_package_config_file(
+    "${PROJECT_SOURCE_DIR}/cmake/${PROJECT_NAME}-config.cmake.in"
+    "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
+    INSTALL_DESTINATION "share/cmake/${PROJECT_NAME}")
 
-if (EXPECTED_BUILD_RPM)
-  list(APPEND binary-generators "RPM")
-endif()
+  write_basic_package_version_file(
+    "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config-version.cmake"
+    COMPATIBILITY SameMajorVersion
+    ARCH_INDEPENDENT)
+
+  install(TARGETS expected
+    EXPORT ${PROJECT_NAME}-targets
+    INCLUDES DESTINATION "${CMAKE_INSTALL_DATADIR}")
+
+  install(EXPORT ${PROJECT_NAME}-targets
+    DESTINATION "${CMAKE_INSTALL_DATADIR}/cmake/${PROJECT_NAME}"
+    NAMESPACE tl::
+    FILE "${PROJECT_NAME}-targets.cmake")
+
+  install(FILES
+    "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config-version.cmake"
+    "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
+    DESTINATION "${CMAKE_INSTALL_DATADIR}/cmake/${PROJECT_NAME}")
+
+  install(DIRECTORY "include/" TYPE INCLUDE)
+
+  if(EXPECTED_BUILD_TESTS)
+    set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
+    set(CATCH_INSTALL_HELPERS OFF)
+    set(CATCH_BUILD_TESTING OFF)
+    set(CATCH_INSTALL_DOCS OFF)
+    FetchContent_Declare(Catch2 URL
+      https://github.com/catchorg/Catch2/archive/v2.9.2.zip)
+    FetchContent_MakeAvailable(Catch2)
+
+    file(GLOB test-sources CONFIGURE_DEPENDS tests/*.cpp)
+    list(FILTER test-sources EXCLUDE REGEX "tests/test.cpp")
+    add_executable(${PROJECT_NAME}-tests "${test-sources}")
+    target_compile_options(${PROJECT_NAME}-tests PRIVATE
+      $<$<NOT:$<CXX_COMPILER_ID:MSVC>>:-Wall -Wextra>)
+
+    target_link_libraries(${PROJECT_NAME}-tests
+      PRIVATE
+        Catch2::Catch2
+        expected)
+    add_test(NAME tl::expected::tests COMMAND ${PROJECT_NAME}-tests)
+  endif()
+
+  if (NOT EXPECTED_BUILD_PACKAGE)
+    return()
+  endif()
+
+  list(APPEND source-generators TBZ2 TGZ TXZ ZIP)
+
+  if (CMAKE_HOST_WIN32)
+    list(APPEND binary-generators "WIX")
+  endif()
+
+  if (EXPECTED_BUILD_PACKAGE_DEB)
+    list(APPEND binary-generators "DEB")
+  endif()
+
+  if (EXPECTED_BUILD_RPM)
+    list(APPEND binary-generators "RPM")
+  endif()
 
 
-set(CPACK_SOURCE_GENERATOR ${source-generators})
-set(CPACK_GENERATOR ${binary-generators})
+  set(CPACK_SOURCE_GENERATOR ${source-generators})
+  set(CPACK_GENERATOR ${binary-generators})
 
-set(CPACK_PACKAGE_FILE_NAME "${PROJECT_NAME}-${PROJECT_VERSION}")
-set(CPACK_SOURCE_PACKAGE_FILE_NAME "${CPACK_PACKAGE_FILE_NAME}")
+  set(CPACK_PACKAGE_FILE_NAME "${PROJECT_NAME}-${PROJECT_VERSION}")
+  set(CPACK_SOURCE_PACKAGE_FILE_NAME "${CPACK_PACKAGE_FILE_NAME}")
 
-set(CPACK_DEBIAN_PACKAGE_MAINTAINER "Sy Brand")
+  set(CPACK_DEBIAN_PACKAGE_MAINTAINER "Sy Brand")
 
-list(APPEND CPACK_SOURCE_IGNORE_FILES /.git/ /build/ .gitignore .DS_Store)
+  list(APPEND CPACK_SOURCE_IGNORE_FILES /.git/ /build/ .gitignore .DS_Store)
 
-include(CPack)
+  include(CPack)
 
+endif()
\ No newline at end of file