diff --git a/requirements.txt b/requirements.txt
index c0654147..d09327c1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,5 @@
-matplotlib==3.5.0
+matplotlib==3.5.1
+numpy==1.21.5 # for matplotlib compatibility
 unidiff
 docker==4.1.0; python_version < '3.10'
 docker==5.0.3; python_version >= '3.10'  # (Jammy)