add flake devshell

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1736817698,
+        "narHash": "sha256-1m+JP9RUsbeLVv/tF1DX3Ew9Vl/fatXnlh/g5k3jcSk=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "2b1fca3296ddd1602d2c4f104a4050e006f4b0cb",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,40 @@
+{
+  description = "Development Shell For this repository";
+
+  nixConfig = {
+    extra-substituters = [
+      "https://nix-community.cachix.org"
+    ];
+    extra-trusted-public-keys = [
+      "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
+    ];
+  };
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+  };
+
+  outputs =
+    {
+      nixpkgs,
+      ... }:
+    let
+      system = "x86_64-linux";
+      pkgs = import nixpkgs {
+        inherit system;
+        config.allowUnfree = true;
+      };
+    in
+    {
+      # TODO: i want to compile my keyboard using nix as a build system
+      devShells."${system}".default = pkgs.mkShell {
+        packages = with pkgs; [
+          keymapviz
+          qmk
+        ];
+        shellHook = ''
+          echo 'Welcome to my keyboard development.'
+        '';
+      };
+    };
+}