added justfile.

flake.nix

@@ -2,21 +2,21 @@
   description = "A very basic flake";
 
   inputs = {
-    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { self, nixpkgs }:
-      let
-      supportedSystems = [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ];
-      forEachSupportedSystem = f: nixpkgs.lib.genAttrs supportedSystems (system: f {
-        pkgs = import nixpkgs { inherit system; };
-      });
+  outputs = {
+    self,
+    nixpkgs,
+    flake-utils,
+  }:
+    flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = import nixpkgs {inherit system;};
     in
-    {
-      devShells = forEachSupportedSystem ({ pkgs }: {
-        default = pkgs.mkShell {
-          packages = with pkgs; [ texliveFull ];
+      with pkgs; {
+        devShells.default = mkShell {
+          buildInputs = [texliveFull];
         };
       });
-    };
 }