basic frankenphp support

fixes #17

nix/image/php-ext.nix

@@ -0,0 +1,44 @@
+{
+  lib,
+  php,
+  debug ? false,
+  enableBlackfire ? true,
+}: let
+  inherit (builtins) compareVersions;
+  inherit (lib) optionals;
+  withBlackfire = enableBlackfire && !debug && ((compareVersions php.version "8.1.0") == 1);
+in
+  {
+    enabled,
+    all,
+  }:
+    enabled
+    ++ (with all;
+      [
+        xdebug
+        excimer
+        inotify
+        redis
+        oci8
+        zip
+        pdo
+        pdo_pgsql
+        pdo_sqlite
+        pdo_mysql
+        pgsql
+        intl
+        curl
+        mbstring
+        pcntl
+        ldap
+        exif
+        gmp
+        apcu
+        ffi
+      ]
+      ++ optionals (!debug) [
+        smbclient # this breaks the build for no apparent reason
+      ]
+      ++ optionals withBlackfire [
+        blackfire
+      ])