diff --git a/pkgs/by-name/mm64baserom/package.nix b/pkgs/by-name/mm64baserom/package.nix
new file mode 100644
index 000000000..94f232f30
--- /dev/null
+++ b/pkgs/by-name/mm64baserom/package.nix
@@ -0,0 +1,8 @@
+# this derivation is consumed by the upstream `zelda64recomp` package via overlay/override.
+# it replaces the upstream `requireFile` expression with an equivalent expression that's actually buildable (what a concept).
+{ fetchzip }:
+fetchzip {
+  name = "mm.us.rev1.rom.z64";
+  url = "https://serve.emulatorgames.net/roms/nintendo-64/Legend%20of%20Zelda,%20The%20-%20Majora's%20Mask%20(U)%20%5b!%5d.zip";
+  hash = "sha256-gZ2WUFaBYYKE8EOlvj0/5TwNKsFeiVxMGbJMSgAGVuA=";
+}