diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3f307f0..eb30889 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -248,20 +248,26 @@
 endif()
 
 if(CMAKE_SYSTEM_NAME STREQUAL Darwin)
-  add_custom_target(module-map-symlinks
-                    ALL
-                    COMMAND
-                      ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/dispatch/darwin/module.modulemap" "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
-                    COMMAND
-                      ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/private/darwin/module.modulemap" "${CMAKE_SOURCE_DIR}/private/module.modulemap")
+  add_custom_command(OUTPUT
+                       "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
+                       "${CMAKE_SOURCE_DIR}/private/module.modulemap"
+                     COMMAND
+                       ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/dispatch/darwin/module.modulemap" "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
+                     COMMAND
+                       ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/private/darwin/module.modulemap" "${CMAKE_SOURCE_DIR}/private/module.modulemap")
 else()
-  add_custom_target(module-map-symlinks
-                    ALL
-                    COMMAND
-                      ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/dispatch/generic/module.modulemap" "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
-                    COMMAND
-                      ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/private/generic/module.modulemap" "${CMAKE_SOURCE_DIR}/private/module.modulemap")
+  add_custom_command(OUTPUT
+                       "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
+                       "${CMAKE_SOURCE_DIR}/private/module.modulemap"
+                     COMMAND
+                       ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/dispatch/generic/module.modulemap" "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
+                     COMMAND
+                       ${CMAKE_COMMAND} -E create_symlink "${CMAKE_SOURCE_DIR}/private/generic/module.modulemap" "${CMAKE_SOURCE_DIR}/private/module.modulemap")
 endif()
+add_custom_target(module-map-symlinks
+                  DEPENDS
+                     "${CMAKE_SOURCE_DIR}/dispatch/module.modulemap"
+                     "${CMAKE_SOURCE_DIR}/private/module.modulemap")
 configure_file("${CMAKE_SOURCE_DIR}/cmake/config.h.in"
                "${CMAKE_BINARY_DIR}/config/config_ac.h")
 add_definitions(-DHAVE_CONFIG_H)
diff --git a/cmake/modules/SwiftSupport.cmake b/cmake/modules/SwiftSupport.cmake
index b7a3e76..3f19070 100644
--- a/cmake/modules/SwiftSupport.cmake
+++ b/cmake/modules/SwiftSupport.cmake
@@ -4,7 +4,7 @@
 function(add_swift_library library)
   set(options)
   set(single_value_options MODULE_NAME;MODULE_LINK_NAME;MODULE_PATH;MODULE_CACHE_PATH;OUTPUT;TARGET)
-  set(multiple_value_options SOURCES;SWIFT_FLAGS;CFLAGS)
+  set(multiple_value_options SOURCES;SWIFT_FLAGS;CFLAGS;DEPENDS)
 
   cmake_parse_arguments(ASL "${options}" "${single_value_options}" "${multiple_value_options}" ${ARGN})
 
@@ -61,6 +61,7 @@
                      DEPENDS
                        ${ASL_SOURCES}
                        ${CMAKE_SWIFT_COMPILER}
+                       ${ASL_DEPENDS}
                      COMMAND
                        ${CMAKE_COMMAND} -E make_directory ${module_directory}
                      COMMAND
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 11c3a3d..2336908 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -100,9 +100,9 @@
                       -fmodule-map-file=${CMAKE_SOURCE_DIR}/dispatch/module.modulemap
                     SWIFT_FLAGS
                       -I ${CMAKE_SOURCE_DIR}
-                      ${swift_optimization_flags})
-  add_dependencies(swiftDispatch
-                     module-map-symlinks)
+                      ${swift_optimization_flags}
+                    DEPENDS
+                      ${CMAKE_SOURCE_DIR}/dispatch/module.modulemap)
   target_sources(dispatch
                  PRIVATE
                    swift/DispatchStubs.cc