diff --git a/docs/requirements.txt b/docs/requirements.txt
index 6746934..424dc41 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,4 +1,5 @@
 pipenv
 sphinx>=6.1.3
+numpydoc
 docutils>=0.19
 furo==2021.11.16