nix: add flake

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1722062969,
+        "narHash": "sha256-QOS0ykELUmPbrrUGmegAUlpmUFznDQeR4q7rFhl8eQg=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "b73c2221a46c13557b1b3be9c2070cc42cf01eb3",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,11 @@
+{
+  description = "A very basic flake";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
+  };
+
+  outputs = { self, nixpkgs }: {
+    devShells.x86_64-linux.default = import ./shell.nix { pkgs = nixpkgs.legacyPackages.x86_64-linux; };
+  };
+}