diff --git a/.github/workflows/extbuild.yml b/.github/workflows/extbuild.yml
index a067094..6567f3a 100644
--- a/.github/workflows/extbuild.yml
+++ b/.github/workflows/extbuild.yml
@@ -24,11 +24,6 @@ jobs:
     steps:
       - id: checkout-share
         uses: actions/checkout@v4
-      - id: checkout-genf90
-        uses: actions/checkout@v4
-        with:
-          path: ${GITHUB_WORKSPACE}/genf90
-          repository: PARALLELIO/genf90
       - id: load-env
         run: |
           sudo apt-get update
@@ -75,7 +70,7 @@ jobs:
           src_root: ${GITHUB_WORKSPACE}
           cmake_flags: " -Wno-dev -DCMAKE_BUILD_TYPE=DEBUG -DWERROR=ON  -DCMAKE_Fortran_FLAGS=\"-DCPRGNU -g -Wall \
           -ffree-form -ffree-line-length-none -fallow-argument-mismatch\" \
-          -DGENF90_PATH=${GITHUB_WORKSPACE}/genf90 -DCMAKE_MODULE_PATH=$ESMF_ROOT/cmake"
+          -DCMAKE_MODULE_PATH=$ESMF_ROOT/cmake"
       - name: Test CDEPS
         run: |
           cd build-share
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 47b0d59..9b7d46c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -54,16 +54,49 @@ set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} ${ESMF_F90COMPILEPATHS}")
 if("${COMPILER}" STREQUAL "nag")
   set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -D__NAG__")
 endif()
-file(GLOB GENF90SOURCES "src/*.F90.in")
+set(GENF90SOURCES src/shr_assert_mod.F90 src/shr_frz_mod.F90 src/shr_infnan_mod.F90)
+#file(GLOB GENF90SOURCES "src/*.F90.in")
 set(ENABLE_GENF90 ON)
+
+#===== genf90 =====
+if (DEFINED GENF90_PATH)
+  add_custom_target(genf90
+    DEPENDS ${GENF90_PATH}/genf90.pl)
+else ()
+  ExternalProject_Add (genf90
+    PREFIX ${CMAKE_CURRENT_BINARY_DIR}/genf90
+    GIT_REPOSITORY https://github.com/PARALLELIO/genf90
+    GIT_TAG update_cmake_interface  
+    UPDATE_COMMAND ""
+    CONFIGURE_COMMAND ""
+    BUILD_COMMAND ""
+    INSTALL_COMMAND "")
+  ExternalProject_Get_Property (genf90 SOURCE_DIR)
+  set (GENF90_PATH ${SOURCE_DIR})
+  unset (SOURCE_DIR)
+endif ()
+
+
 set(GENF90 "${GENF90_PATH}/genf90.pl")
-include(${CMAKE_SOURCE_DIR}/cmake/genf90_utils.cmake)
-process_genf90_source_list("${GENF90SOURCES}" ${CMAKE_CURRENT_BINARY_DIR} SHAREGENF90SRC)
+#include(${GENF90_PATH}/cmake/genf90_utils.cmake)
+
+#===== Fortran Source Generation with GenF90 =====
+foreach (SRC_FILE IN LISTS GENF90SOURCES)
+  list(APPEND SHAREGENF90SRC ${SRC_FILE})
+  add_custom_command (OUTPUT ${SRC_FILE}
+    COMMAND ${GENF90_PATH}/genf90.pl
+    ${CMAKE_CURRENT_SOURCE_DIR}/${SRC_FILE}.in > ${SRC_FILE}
+    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/${SRC_FILE}.in genf90)
+endforeach ()
+
+#process_genf90_source_list("${GENF90SOURCES}" ${CMAKE_CURRENT_BINARY_DIR} SHAREGENF90SRC)
+
 file(GLOB SOURCES "src/*.c" "src/*.F90" "src/water_isotopes/*.F90" "RandNum/src/*.F90" "RandNum/src/*/*.F90" "RandNum/src/*/*.c")
-list(APPEND SOURCES "${SHAREGENF90SRC}")
+#list(APPEND SOURCES "${SHAREGENF90SRC}")
 #add_definitions(-DCPRINTEL)
-
-add_library(share STATIC ${SOURCES})
+file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/src)
+add_library(share STATIC ${SOURCES} ${SHAREGENF90SRC})
+add_dependencies (share genf90)
 target_include_directories(share PRIVATE include RandNum/include)
 #target_include_directories(share PRIVATE RandNum/include)