diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f24cc4bc01ca5e7a16f093fdbd8028e08d7fce3b..c28d5b9cc6534c01849654bb0d6a5056818f817d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -47,6 +47,8 @@ reuse:
 # among others, the "rules" section.
 build-docs:
   extends: [.workspace, .build-docs]
+  variables:
+    CI_ONIRO_INSTANCE_SIZE: s3.large.2
   script:
     - !reference [.workspace, script]
     - !reference [.build-docs, script]