diff --git a/circt.nix b/circt.nix
index b5a7ffd..e01ac36 100644
--- a/circt.nix
+++ b/circt.nix
@@ -33,7 +33,7 @@ let
     in
       "g${date}_${rev}";
 
-  tag = "1.84.0";
+  tag = "1.85.0";
   versionSuffix = mkVer circt-src;
   version = "${tag}${versionSuffix}";
 in stdenv.mkDerivation {