diff --git a/pytato/scalar_expr.py b/pytato/scalar_expr.py
index a84ca09aa..04bf69cb4 100644
--- a/pytato/scalar_expr.py
+++ b/pytato/scalar_expr.py
@@ -30,11 +30,11 @@
 
 from pymbolic.mapper import (WalkMapper as WalkMapperBase, IdentityMapper as
         IdentityMapperBase)
-from pymbolic.mapper.substitutor import (SubstitutionMapper as
+from pymbolic.mapper.substitutor import (CachedSubstitutionMapper as
         SubstitutionMapperBase)
-from pymbolic.mapper.dependency import (DependencyMapper as
+from pymbolic.mapper.dependency import (CachedDependencyMapper as
         DependencyMapperBase)
-from pymbolic.mapper.evaluator import (EvaluationMapper as
+from pymbolic.mapper.evaluator import (CachedEvaluationMapper as
         EvaluationMapperBase)
 from pymbolic.mapper.distributor import (DistributeMapper as
         DistributeMapperBase)