diff --git a/containers/jug/setup_detectors.py b/containers/jug/setup_detectors.py
index a25ad9fba1464dcefbba4e06b076917acce35528..c9389cc0de789eb4d751478c030c5e935bc9810c 100755
--- a/containers/jug/setup_detectors.py
+++ b/containers/jug/setup_detectors.py
@@ -100,7 +100,7 @@ if __name__ == '__main__':
             ## patches
             if cfg.get('patches'):
                 for patch in cfg['patches']:
-                    cmd = ['curl -L {patch} | patch -p1 -d/tmp/det']
+                    cmd = [f'curl -L {patch} | patch -p1 -d/tmp/det']
                     print(' '.join(cmd))
                     subprocess.check_call(' '.join(cmd), shell=True)
             ## build