diff --git a/luamml-patches-amsmath.sty b/luamml-patches-amsmath.sty
index f8933c4..fa6ec7e 100644
--- a/luamml-patches-amsmath.sty
+++ b/luamml-patches-amsmath.sty
@@ -406,3 +406,10 @@
     }
   }
 }
+
+\cs_set:Npn \env@cases {
+  \let \@ifnextchar \new@ifnextchar
+  \left \lbrace
+    \def \arraystretch {1.2}
+    \array {@{}l@{\quad \luamml_flag_ignore:}l@{}}
+}