nix: add development environment

Signed-off-by: Onur Özkan <work@onurozkan.dev>

flake.nix

@@ -0,0 +1,33 @@
+{
+  description = "Kaptan development environment";
+
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+
+  outputs = { nixpkgs, ... }:
+    let
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+      ];
+      forAllSystems = nixpkgs.lib.genAttrs systems;
+    in
+    {
+      devShells = forAllSystems (system:
+        let
+          pkgs = nixpkgs.legacyPackages.${system};
+          python = pkgs.python3.withPackages (pythonPackages: with pythonPackages; [
+            pymavlink
+            pyserial
+          ]);
+        in
+        {
+          default = pkgs.mkShell {
+            packages = [
+              pkgs.rustup
+              pkgs.dfu-util
+              python
+            ];
+          };
+        });
+    };
+}