diff --git a/pkgs/development/tools/parsing/re-flex/default.nix b/pkgs/development/tools/parsing/re-flex/default.nix
index 9b31a5ab5488..60bdaa4de103 100644
--- a/pkgs/development/tools/parsing/re-flex/default.nix
+++ b/pkgs/development/tools/parsing/re-flex/default.nix
@@ -6,13 +6,13 @@
 
 stdenv.mkDerivation rec {
   pname = "re-flex";
-  version = "4.4.0";
+  version = "4.5.0";
 
   src = fetchFromGitHub {
     owner = "Genivia";
     repo = "RE-flex";
     rev = "v${version}";
-    hash = "sha256-yMFz3KrB1eIzGg0LB3U0H+XQz/DKhJOyiG8ScW9Lm7A=";
+    hash = "sha256-Dc/nnzJtkLgfmYnilA9FtOPtlOwTqgXtNVWhypFu5hs=";
   };
 
   outputs = [ "out" "bin" "dev" ];