diff --git a/pkgs/development/tools/haskell/BNFC/default.nix b/pkgs/development/tools/haskell/BNFC/default.nix
index c06b5eacc24..e737a02a4ac 100644
--- a/pkgs/development/tools/haskell/BNFC/default.nix
+++ b/pkgs/development/tools/haskell/BNFC/default.nix
@@ -2,8 +2,8 @@
 
 cabal.mkDerivation (self: {
   pname = "BNFC";
-  version = "2.4.2.0";
-  sha256 = "0nnalzsql1k5y3s93g5y2hy2gcdsrbi8r7cwzmdcy4vyy589pin0";
+  version = "2.4.2.1";
+  sha256 = "0a6ic9mqkxk2gql7dzik2bhm5iikgx035wxlz8iafxf45159dl14";
   isLibrary = false;
   isExecutable = true;
   buildDepends = [ mtl ];