diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..1157b0c
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,31 @@
+{
+  description = "selenium — lunar/poetic esoteric language that compiles to C";
+
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
+
+  outputs = { self, nixpkgs }:
+    let
+      systems = [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ];
+      forAllSystems = nixpkgs.lib.genAttrs systems;
+    in {
+      devShells = forAllSystems (system:
+        let pkgs = nixpkgs.legacyPackages.${system}; in
+        {
+          default = pkgs.mkShell {
+            packages = with pkgs; [
+              python3
+              python3Packages.pip
+              python3Packages.virtualenv
+              python3Packages.setuptools
+            ];
+
+            shellHook = ''
+              echo "selenium dev shell ready (Python 3 + setuptools)"
+            '';
+          };
+        }
+      );
+
+      formatter = forAllSystems (pkgs: pkgs.nixfmt-rfc-style);
+    };
+}