diff --git a/scripts/nightly.yaml b/scripts/nightly.yaml
index 3a439d3a9..b3130f5a8 100644
--- a/scripts/nightly.yaml
+++ b/scripts/nightly.yaml
@@ -55,7 +55,7 @@ stages:
         cd ..
         cd doc
         python mk_api_doc.py --z3py-package-path=../build/python/z3
-        ocamldoc -html -d api/html/ml -sort -hide Z3 -I +z3arith -I ../build/api/ml ../build/api/ml/z3enums.mli ../build/api/ml/z3.mli
+        ocamldoc -html -d api/html/ml -sort -hide Z3 -I +zarith -I ../build/api/ml ../build/api/ml/z3enums.mli ../build/api/ml/z3.mli
         cd ..
     - script: zip -r api.zip doc/api
     - script: cp api.zip $(Build.ArtifactStagingDirectory)/.