diff --git a/cubicweb_elasticsearch/__pkginfo__.py b/cubicweb_elasticsearch/__pkginfo__.py
index 6ed026c72fe27a6fddd82bc30060f15423ec0727..71ee4e17987cd832aac41fdb7749193233aa2845 100644
--- a/cubicweb_elasticsearch/__pkginfo__.py
+++ b/cubicweb_elasticsearch/__pkginfo__.py
@@ -14,7 +14,8 @@ description = "Simple ElasticSearch indexing integration for CubicWeb"
 web = "https://forge.extranet.logilab.fr/cubicweb/cubes/%s" % distname
 
 __depends__ = {
-    "cubicweb": ">= 3.28.0, < 3.35.0",
+    "cubicweb": ">= 3.28.0, < 3.36.0",
+    "six": ">= 1.4.0",
     "cwtags": None,
     "elasticsearch": ">=7.0.0,<8.0.0",
     "elasticsearch-dsl": ">=7.0.0,<8.0.0",