diff --git a/CMakeLists.txt b/CMakeLists.txt
index 65992691c8b..8f68aab4ea3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -59,7 +59,10 @@ function(message)
 endfunction()
 
 option(PROFILE_TESTS "Profile tests" OFF)
-set(PYTHON python3)
+
+# Add CCF_PYTHON_PRELAUNCH=unbuffer to env when calling cmake to get coloured
+# test output
+set(PYTHON "$ENV{CCF_PYTHON_PRELAUNCH}" python3)
 
 set(DISTRIBUTE_PERF_TESTS
     ""