diff -Naur ORIG/CMakeLists.txt PATCHED/CMakeLists.txt
--- ORIG/CMakeLists.txt	2026-04-14 17:46:07.152657067 +0000
+++ PATCHED/CMakeLists.txt	2026-04-14 17:46:07.152657067 +0000
@@ -1,10 +1,12 @@
 # BASIC DEFINITIONS ====================================================
 
 # define minimum version of cmake
-cmake_minimum_required (VERSION 3.15)
+cmake_minimum_required(VERSION 3.15...4.0)
 
 cmake_policy(SET CMP0086 OLD)
 cmake_policy(SET CMP0078 OLD)
+cmake_policy(SET CMP0169 OLD)
+
 
 # define project name, version and its languages
 project(apfel LANGUAGES C CXX Fortran)
@@ -85,23 +87,29 @@
   endif()
 endif()
 if (LHAPDF_CONFIG AND APFEL_ENABLE_LHAPDF)
-  exec_program(${LHAPDF_CONFIG}
-    ARGS --cxxflags
+  execute_process(
+    COMMAND ${LHAPDF_CONFIG} --cxxflags
     OUTPUT_VARIABLE LHAPDF_CXX_FLAGS
+    OUTPUT_STRIP_TRAILING_WHITESPACE
   )
-  set(LHAPDF_CXX_FLAGS ${LHAPDF_CXX_FLAGS} CACHE STRING INTERNAL)
-  exec_program(${LHAPDF_CONFIG}
-    ARGS --libdir
+  set(LHAPDF_CXX_FLAGS "${LHAPDF_CXX_FLAGS}" CACHE STRING INTERNAL)
+
+  execute_process(
+    COMMAND ${LHAPDF_CONFIG} --libdir
     OUTPUT_VARIABLE LHAPDF_LIBDIR
+    OUTPUT_STRIP_TRAILING_WHITESPACE
   )
+
   find_library(LHAPDF_LIBRARY NAMES LHAPDF PATHS ${LHAPDF_LIBDIR})
-  set(LHAPDF_LIBRARIES ${LHAPDF_LIBRARY} CACHE STRING INTERNAL)
+  set(LHAPDF_LIBRARIES "${LHAPDF_LIBRARY}" CACHE STRING INTERNAL)
 
-  exec_program(${LHAPDF_CONFIG}
-    ARGS --incdir
+  execute_process(
+    COMMAND ${LHAPDF_CONFIG} --incdir
     OUTPUT_VARIABLE LHAPDF_INCLUDE_DIRS
+    OUTPUT_STRIP_TRAILING_WHITESPACE
   )
-  set(LHAPDF_INCLUDE_DIRS ${LHAPDF_INCLUDE_DIRS} CACHE STRING INTERNAL)
+  set(LHAPDF_INCLUDE_DIRS "${LHAPDF_INCLUDE_DIRS}" CACHE STRING INTERNAL)
+
   message(STATUS "APFEL: LHAPDF_INCLUDE_DIRS=${LHAPDF_INCLUDE_DIRS} LHAPDF_LIBRARIES=${LHAPDF_LIBRARIES}")
 else()
   add_compile_definitions(NOLHAPDF)
@@ -199,9 +207,9 @@
 
 ## Include directories #################################################
 
-include_directories(${PROJECT_SOURCE_DIR}/include)
-include_directories(${PROJECT_BINARY_DIR}/include)
-include_directories(${PROJECT_SOURCE_DIR}/src)
+#include_directories(${PROJECT_SOURCE_DIR}/include)
+#include_directories(${PROJECT_BINARY_DIR}/include)
+#include_directories(${PROJECT_SOURCE_DIR}/src)
 
 
 
@@ -213,7 +221,9 @@
 
 # Shared libraries  ####################################################
 add_library(APFEL SHARED ${libAPFELCCWrapObs_la_SOURCES} ${libAPFELCCWrapEvol_la_SOURCES} ${libAPFELCore_la_SOURCES})
-target_include_directories(APFEL PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
+target_include_directories(APFEL PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src> 
+                                        $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include> 
+                                        $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
 target_link_libraries(APFEL ${LHAPDF_LIBRARIES})
 if(CMAKE_SYSTEM_NAME MATCHES "Linux")
   target_link_options(APFEL PRIVATE "LINKER:-z,defs")
@@ -230,7 +240,9 @@
 add_library(APFEL::APFEL ALIAS APFEL)
 
 add_library(APFELevol SHARED ${libAPFELCCWrapEvol_la_SOURCES} ${libAPFELevol_la_SOURCES})
-target_include_directories(APFELevol PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
+target_include_directories(APFELevol PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src> 
+                                        $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include> 
+                                        $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
 target_link_libraries(APFELevol ${LHAPDF_LIBRARIES} APFEL)
 if(CMAKE_SYSTEM_NAME MATCHES "Linux")
   target_link_options(APFELevol PRIVATE "LINKER:-z,defs")
@@ -248,7 +260,9 @@
 
 # Static libraries  ####################################################
 add_library(APFEL_static STATIC ${libAPFELCCWrapObs_la_SOURCES} ${libAPFELCCWrapEvol_la_SOURCES} ${libAPFELCore_la_SOURCES})
-target_include_directories(APFEL_static PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
+target_include_directories(APFEL_static PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src> 
+                                        $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include> 
+                                        $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
 target_link_libraries(APFEL_static ${LHAPDF_LIBRARIES})
 target_compile_features(APFEL_static PRIVATE cxx_std_11)
 set_target_properties(APFEL_static PROPERTIES 
@@ -260,7 +274,9 @@
     )
 
 add_library(APFELevol_static STATIC ${libAPFELCCWrapEvol_la_SOURCES} ${libAPFELevol_la_SOURCES})
-target_include_directories(APFELevol_static PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
+target_include_directories(APFELevol_static PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src> 
+                                        $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include> 
+                                        $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>  ${LHAPDF_INCLUDE_DIRS})
 target_link_libraries(APFELevol_static ${LHAPDF_LIBRARIES})
 target_compile_features(APFELevol_static PRIVATE cxx_std_11)
 set_target_properties(APFELevol_static PROPERTIES 
