diff --git a/release.nix b/release.nix
index 33b3db5673..6708719094 100644
--- a/release.nix
+++ b/release.nix
@@ -23,7 +23,7 @@ let
         inherit officialRelease;
 
         buildInputs =
-          [ curl bison flex2535 perl libxml2 libxslt w3m bzip2
+          [ curl bison flex perl libxml2 libxslt w3m bzip2
             tetex dblatex nukeReferences pkgconfig sqlite git
           ];