use correct musl stdenv on aarch64-linux

Author: Mic92

flake.nix

@@ -90,11 +90,17 @@
             buildPackages = final.buildPackages;
           };
 
-          nix-installer-static = installerPackage {
-            pkgs = final.pkgsCross.musl64;
-            stdenv = final.pkgsCross.musl64.stdenv;
-            buildPackages = final.pkgsBuildHost;
-          };
+          nix-installer-static =
+            let
+              muslPkgs = if final.stdenv.hostPlatform.isAarch64
+                then final.pkgsCross.aarch64-multiplatform-musl
+                else final.pkgsCross.musl64;
+            in
+            installerPackage {
+              pkgs = muslPkgs;
+              stdenv = muslPkgs.stdenv;
+              buildPackages = final.pkgsBuildHost;
+            };
         };