diff --git a/pkgs/by-name/op/opendmarc/package.nix b/pkgs/by-name/op/opendmarc/package.nix
index 815abcd88711..34bafbc67d8b 100644
--- a/pkgs/by-name/op/opendmarc/package.nix
+++ b/pkgs/by-name/op/opendmarc/package.nix
@@ -27,6 +27,11 @@ stdenv.mkDerivation rec {
     "doc"
   ];
 
+  env.NIX_CFLAGS_COMPILE = toString [
+    # gcc15 build failure
+    "-std=gnu17"
+  ];
+
   buildInputs = [ perl ];
   nativeBuildInputs = [
     autoreconfHook