diff --git a/.readthedocs.yml b/.readthedocs.yml
index bb991cc4..47fffd29 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -1,11 +1,13 @@
 version: 2
 
 build:
+  os: ubuntu-22.04
+  tools:
+    python: '3.8'
   apt_packages:
   - gfortran      # This is necessary for the `sisl` dependency of `aiida-siesta`
 
 python:
-  version: 3.8
   install:
   - method: pip
     path: .