diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index f8b2891..33c2a61 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -8,8 +8,12 @@
 # Required
 version: 2
 
+build:
+  os: ubuntu-20.04
+  tools:
+    python: "3"
+
 python:
-  version: "3.x"
   install:
     - requirements: docs/requirements.txt
     - requirements: requirements.txt