diff --git a/owlps-positioner/CMakeLists.txt b/owlps-positioner/CMakeLists.txt
index 37001e1..355b0b1 100644
--- a/owlps-positioner/CMakeLists.txt
+++ b/owlps-positioner/CMakeLists.txt
@@ -167,8 +167,17 @@ set(TESTS_SRC_FILES
   )
 
 # Create the test runner's source
+set(TEST_POSITIONER_FILE_DEPS
+  ${TESTS_SRC_FILES}
+  ${TESTS_DIR}/valuetraits.hh
+  ${TESTS_DIR}/testutil.hh)
 add_custom_command(OUTPUT test_positioner.cc
-  COMMAND cxxtestgen --error-printer --include=${TESTS_DIR}/valuetraits.hh --include=${TESTS_DIR}/testutil.hh -o test_positioner.cc ${TESTS_SRC_FILES})
+  COMMAND cxxtestgen --error-printer
+  --include=${TESTS_DIR}/valuetraits.hh
+  --include=${TESTS_DIR}/testutil.hh -o test_positioner.cc
+  ${TESTS_SRC_FILES}
+  DEPENDS ${TEST_POSITIONER_FILE_DEPS})
+
 
 # Compile the test runner
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})