Add flake for PHP 8.4

Author: dantleech

flake.lock

@@ -0,0 +1,57 @@
+# this is a WIP flake for development and experimentation only
+{
+  description = "phpactor/phpactor";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+  };
+
+  outputs = inputs @ {
+    self,
+    flake-parts,
+    ...
+  }:
+    flake-parts.lib.mkFlake {inherit inputs;} {
+      # This flake is for Linux (x86) and Apple (darwin) systems
+      # If you need more systems, inspect `nixpkgs.lib.systems.flakeExposed` and
+      # add them to this list.
+      #
+      # $ nix repl "<nixpkgs>"
+      # nix-repl> lib.systems.flakeExposed
+      systems = ["x86_64-linux" "aarch64-linux"];
+
+      perSystem = {
+        pkgs,
+        system,
+        ...
+      }: let 
+        phpWithXdebug = (pkgs.php84.buildEnv {
+          extensions = ({ enabled, all }: enabled ++ (with all; [
+            xdebug
+          ]));
+          extraConfig = ''
+            xdebug.mode=debug
+          '';
+        });
+      in {
+        # Run `nix fmt` to reformat the nix files
+        formatter = pkgs.alejandra;
+
+        # Run `nix develop` to enter the development shell
+        devShells.default = pkgs.mkShellNoCC {
+          name = "php-devshell";
+
+          buildInputs = [
+            phpWithXdebug
+            pkgs.php84.packages.composer
+          ];
+          shellHook = ''
+          if [ ! -d ".venv" ]; then
+            python3 -m venv .venv;
+          fi
+          source .venv/bin/activate;'';
+        };
+      };
+    };
+}
+