diff --git a/CMakeLists.txt b/CMakeLists.txt

index c5d5f610..7095173e 100644

--- a/CMakeLists.txt

+++ b/CMakeLists.txt

@@ -275,6 +275,7 @@ endif ()



Target.

add_executable (app ${SOURCES} ${RESOURCES})

+add_dependencies (app ext-deps)

set_target_properties (app PROPERTIES OUTPUT_NAME lagrange)

target_include_directories (app PUBLIC

 src

diff --git a/Depends.cmake b/Depends.cmake

index 174d5eb6..657f90aa 100644

--- a/Depends.cmake

+++ b/Depends.cmake

@@ -8,6 +8,8 @@ find_program (MESON_EXECUTABLE meson DOC "Meson build system")

find_program (NINJA_EXECUTABLE ninja DOC "Ninja build tool")

include (ExternalProject)



+set (_dependsToBuild)

+

if (ENABLE_HARFBUZZ AND EXISTS ${CMAKE_SOURCE_DIR}/lib/harfbuzz/CMakeLists.txt)

 # Find HarfBuzz with pkg-config.

 if (NOT ENABLE_HARFBUZZ_MINIMAL AND PKG_CONFIG_FOUND)

@@ -30,10 +32,9 @@ if (ENABLE_HARFBUZZ AND EXISTS ${CMAKE_SOURCE_DIR}/lib/harfbuzz/CMakeLists.txt)

                                     --prefix ${_dst}

             BUILD_COMMAND       ${NINJA_EXECUTABLE}

             INSTALL_COMMAND     ${NINJA_EXECUTABLE} install

- STEP_TARGETS install

         )

+ list (APPEND _dependsToBuild harfbuzz-ext)

         add_library (harfbuzz-lib INTERFACE)

- add_dependencies (harfbuzz-lib harfbuzz-ext-install harfbuzz-ext)

         target_include_directories (harfbuzz-lib INTERFACE ${_dst}/include/harfbuzz)

         if (MSYS)

             # Link dynamically.

@@ -97,21 +98,22 @@ if (ENABLE_FRIBIDI AND EXISTS ${CMAKE_SOURCE_DIR}/lib/fribidi)

                                     --prefix ${_dst}

             BUILD_COMMAND       ${NINJA_EXECUTABLE}

             INSTALL_COMMAND     ${NINJA_EXECUTABLE} install

- STEP_TARGETS install

             BUILD_BYPRODUCTS    ${_dst}/lib/libfribidi.a

         )

+ list (APPEND _dependsToBuild fribidi-ext)

     else ()

         message (FATAL_ERROR

             "GNU FriBidi must be built with Meson. Please install Meson and Ninja and try again, or provide FriBidi via pkg-config.")

     endif ()

     add_library (fribidi-lib INTERFACE)

- add_dependencies (fribidi-lib fribidi-ext-install fribidi-ext)

     target_include_directories (fribidi-lib INTERFACE ${_dst}/include)

     target_link_libraries (fribidi-lib INTERFACE ${_dst}/lib/libfribidi.a)

     set (FRIBIDI_FOUND YES)

 endif ()

endif ()



+add_custom_target (ext-deps DEPENDS ${_dependsToBuild})

+

if (NOT EXISTS ${CMAKE_SOURCE_DIR}/lib/the_Foundation/CMakeLists.txt)

 set (INSTALL_THE_FOUNDATION YES)

 find_package (the_Foundation REQUIRED)