diff --git a/docker/python-builder/scripts/install-from-bindep b/docker/python-builder/scripts/install-from-bindep
index 65419433e6..59686bfe34 100755
--- a/docker/python-builder/scripts/install-from-bindep
+++ b/docker/python-builder/scripts/install-from-bindep
@@ -35,7 +35,7 @@ fi
 # Add any requested extras to the list of things to install
 EXTRAS=""
 for extra in $* ; do
-    EXTRAS="${EXTRAS} -f /output/$extra/requirements.txt"
+    EXTRAS="${EXTRAS} -r /output/$extra/requirements.txt"
 done
 
 if [ -f /output/packages.txt ] ; then