diff --git a/requirements.txt b/requirements.txt
index f0140eba236..d4c5ad265a1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 autograd<1.7
 beartype<0.18.0
-dill<0.3.8
+dill<0.3.9
 fastkde>=1.0.24, <1.0.31
 graph-scheduler>=1.1.1, <1.3.0
 graphviz<0.21.0