add compat for sr.ht

.build.yml

@@ -7,7 +7,8 @@ secrets:
 
 tasks:
   - check: |
-      nix flake check
+      cd dotfiles
+      nix-shell --pure --run 'nix-experimental flake check'
   - github_push: |
       set +xv
       cd dotfiles

shell.nix

@@ -0,0 +1,15 @@
+let
+  nixpkgs = import <nixpkgs> {};
+in
+  with nixpkgs;
+  stdenv.mkDerivation {
+    name = "legacy_shell";
+    buildInputs = [
+      (pkgs.writeShellScriptBin "nix-experimental" ''
+        exec ${pkgs.nixUnstable}/bin/nix --experimental-features "nix-command flakes" "$@"
+      '')
+      git
+    ];
+    shellHook = ''
+    '';
+  }