diff --git a/deny.toml b/deny.toml
index 381e6873..549b89a1 100644
--- a/deny.toml
+++ b/deny.toml
@@ -11,6 +11,7 @@ allow = [
     "MIT",
     "Unicode-DFS-2016",
     "WTFPL",
+    "Zlib",
 ]
 
 [advisories]