add flake nix

Author: sfmok

flake.nix

@@ -0,0 +1,34 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    phps.url = "github:fossar/nix-phps";
+    devenv.url = "github:cachix/devenv";
+    systems.url = "github:nix-systems/default";
+  };
+
+  outputs = inputs @ { self, flake-parts, ... }: flake-parts.lib.mkFlake { inherit inputs; } {
+    systems = import inputs.systems;
+
+    imports = [
+      inputs.devenv.flakeModule
+    ];
+
+    perSystem = { config, self', inputs', pkgs, system, lib, ... }: {
+      _module.args.pkgs = import self.inputs.nixpkgs {
+        inherit system;
+        overlays = [
+          inputs.phps.overlays.default
+        ];
+      };
+
+      devenv.shells.default = {
+        name = "php-dev-env";
+
+        packages = [
+          pkgs.php82
+          pkgs.php82.packages.composer
+        ];
+      };
+    };
+  };
+}