diff --git a/pyfstat/grid_based_searches.py b/pyfstat/grid_based_searches.py
index 6c1c46457f073481a3569f217c5df63dae006fd7..2dee0c6b6e43c6a78148a97f7b16e7a0735cda6a 100644
--- a/pyfstat/grid_based_searches.py
+++ b/pyfstat/grid_based_searches.py
@@ -5,6 +5,9 @@ import os
 import logging
 import itertools
 from collections import OrderedDict
+import datetime
+import getpass
+import socket
 
 import numpy as np
 import matplotlib