add rust programming tooling

templates/rust/flake.nix

@@ -0,0 +1,20 @@
+{
+  description = "Basic Rust project";
+  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+  outputs = { self, nixpkgs }:
+    let
+      forAllSystems = nixpkgs.lib.genAttrs [
+        "x86_64-linux"
+        "x86_64-darwin"
+        "aarch64-linux"
+        "aarch64-darwin"
+      ];
+    in {
+      devShells = forAllSystems (system:
+        let pkgs = import nixpkgs { inherit system; };
+        in {
+          default =
+            pkgs.mkShell { buildInputs = with pkgs; [ gcc rustc cargo ]; };
+        });
+    };
+}