diff --git a/src/scikit_build_core/program_search.py b/src/scikit_build_core/program_search.py
index 709503a68..282b5ee09 100644
--- a/src/scikit_build_core/program_search.py
+++ b/src/scikit_build_core/program_search.py
@@ -2,6 +2,7 @@
 
 import contextlib
 import json
+import os
 import shutil
 import subprocess
 import sys
@@ -33,7 +34,11 @@ def __dir__() -> list[str]:
 
 
 # Make sure we don't wait forever for programs to respond
-TIMEOUT = 10 if sys.platform.startswith("win") else 5
+# CI services can be really slow under load
+if os.environ.get("CI", ""):
+    TIMEOUT = 20
+else:
+    TIMEOUT = 10 if sys.platform.startswith("win") else 5
 
 
 class Program(NamedTuple):