diff --git a/external/external_build.cmake b/external/external_build.cmake
index c8fedcf..53037ed 100644
--- a/external/external_build.cmake
+++ b/external/external_build.cmake
@@ -56,19 +56,19 @@ if (ENABLE_SHARP)
   IF(NOT ENABLE_OPENMP)
     SET(SHARP_OPENMP --disable-openmp)
   ENDIF()
-  ExternalProject_Add(sharp
-    URL ${CMAKE_SOURCE_DIR}/external/libsharp-6077806.tar.gz
-    PREFIX ${BUILD_PREFIX}/sharp-prefix
-    BUILD_IN_SOURCE 1 
-    CONFIGURE_COMMAND autoconf && ./configure "CC=${CMAKE_C_COMPILER}" "CXX=${CMAKE_CXX_COMPILER}" --prefix=${DEP_BUILD} ${SHARP_OPENMP}
-    BUILD_COMMAND ${CMAKE_MAKE_PROGRAM}
-    INSTALL_COMMAND echo "No install"
-  )
   SET(CUTILS_LIBRARY ${DEP_BUILD}/lib/libc_utils.a)
   SET(FFTPACK_LIBRARY ${DEP_BUILD}/lib/libfftpack.a)
   SET(SHARP_LIBRARY ${DEP_BUILD}/lib/libsharp.a)
   SET(SHARP_LIBRARIES ${SHARP_LIBRARY} ${FFTPACK_LIBRARY} ${CUTILS_LIBRARY})
   SET(SHARP_INCLUDE_PATH ${DEP_BUILD}/include)
+  ExternalProject_Add(sharp
+    URL ${CMAKE_SOURCE_DIR}/external/libsharp-6077806.tar.gz
+    PREFIX ${BUILD_PREFIX}/sharp-prefix
+    BUILD_IN_SOURCE 1 
+    CONFIGURE_COMMAND autoconf && ./configure "CC=${CMAKE_C_COMPILER}" "CXX=${CMAKE_CXX_COMPILER}" --prefix=${DEP_BUILD} ${SHARP_OPENMP}
+    INSTALL_COMMAND echo "No install"
+    BUILD_BYPRODUCTS ${SHARP_LIBRARIES}
+  )
 endif (ENABLE_SHARP)
 
 
@@ -375,6 +375,7 @@ ExternalProject_Add(omptl
   BUILD_COMMAND echo "No build"
   PATCH_COMMAND patch -p1 -t -N < ${CMAKE_SOURCE_DIR}/external/patch-omptl
   INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_directory ${OMPTL_BUILD_DIR} ${EXT_INSTALL}/include/omptl
+  BUILD_BYPRODUCTS ${EXT_INSTALL}/include/omptl
 )
 include_directories(${EXT_INSTALL}/include)
 ##include_directories(${OMPTL_BUILD_DIR}/src/)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index a4c81e8..2cc4b29 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -92,11 +92,13 @@ if (BUILD_SHARED_LIBS)
      add_library(CosmoTool_static STATIC ${CosmoTool_SRCS} $<TARGET_OBJECTS:CosmoHDF5>)
      target_link_libraries(CosmoTool_static)
      set_property(TARGET CosmoTool_static PROPERTY POSITION_INDEPENDENT_CODE ON)
+     add_dependencies(CosmoTool_static ${cosmotool_DEPS})
   endif(BUILD_STATIC_LIBS)
 else (BUILD_SHARED_LIBS)
   add_library(CosmoTool STATIC ${CosmoTool_SRCS} $<TARGET_OBJECTS:CosmoHDF5>)
   target_link_libraries(CosmoTool)
   set_property(TARGET CosmoTool PROPERTY POSITION_INDEPENDENT_CODE ON)
+  add_dependencies(CosmoTool ${cosmotool_DEPS})
 endif (BUILD_SHARED_LIBS)
 
 IF(NOT COSMOTOOL_PYTHON_PACKAGING)