diff --git a/setup.cfg b/setup.cfg
index 6aa0573..3c5aba1 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -71,10 +71,11 @@ tests =
     pytest-cov
 stan =
     pystan
-    arviz
+    arviz[all]
 all =
     %(doc)s
     %(tests)s
+    %(stan)s
 
 [options.package_data]
 * =