diff --git a/cadCAD/engine/__init__.py b/cadCAD/engine/__init__.py
index e18a0b9f..19fa573f 100644
--- a/cadCAD/engine/__init__.py
+++ b/cadCAD/engine/__init__.py
@@ -241,7 +241,7 @@ def get_final_results(simulations: List[StateHistory],
                 ExpIDs, SubsetIDs, SubsetWindows, original_N, self.additional_objs
             )
 
-            if (self.additional_objs is not None and self.additional_objs['lazy_eval']):
+            if (self.additional_objs is not None and self.additional_objs.get('lazy_eval', False)):
                 final_result = get_final_results_lazy(
                     simulations_results, partial_state_updates, eps, sessions, remote_threshold)
             else:
diff --git a/cadCAD/engine/execution.py b/cadCAD/engine/execution.py
index 29073f4b..abd396a4 100644
--- a/cadCAD/engine/execution.py
+++ b/cadCAD/engine/execution.py
@@ -7,7 +7,6 @@
 import tempfile
 import pickle
 import sys
-from pympler import asizeof
 from memory_profiler import profile
 import dill
 
@@ -115,7 +114,9 @@ def parallelize_simulations(
 ):
 
     print(f'Execution Mode: parallelized')
-    lazy_eval = additional_objs['lazy_eval']
+    lazy_eval = False
+    if (additional_objs):
+        lazy_eval = additional_objs.get('lazy_eval', False)
 
     params = [
         (sim_exec, var_dict, states_list, config, env_processes,