diff --git a/composer.json-dist b/composer.json-dist
index 52c1c4d..44cd627 100644
--- a/composer.json-dist
+++ b/composer.json-dist
@@ -1,31 +1,27 @@
 {
     "name": "kolab/syncroton",
     "description": "The ActiveSync Service for Kolab",
     "license": "AGPL-3.0+",
-    "repositories": [
-        {
-            "type": "vcs",
-            "url": "https://git.kolab.org/diffusion/PNL/php-net_ldap.git"
-        }
-    ],
     "require": {
-        "php": ">=5.4.0",
+        "php": ">=7.2.0",
         "pear/pear-core-minimal": "~1.10.1",
         "pear/net_socket": "~1.2.1",
         "pear/auth_sasl": "~1.1.0",
+        "pear/http_request2": "~2.5.0",
         "pear/net_idna2": "~0.2.0",
         "pear/mail_mime": "~1.10.0",
         "pear/net_smtp": "~1.7.1",
         "pear/net_ldap2": "~2.2.0",
         "pear/net_sieve": "~1.4.0",
         "sabre/vobject": "~4.5.1",
         "kolab/net_ldap3": "dev-master",
         "zf1s/zend-controller": "~1.12.20",
         "zf1s/zend-json": "~1.12.20",
         "zf1s/zend-log": "~1.12.20"
     },
     "require-dev": {
         "guzzlehttp/guzzle": "^7.3.0",
-        "phpunit/phpunit": "^4.8 || ^5.7 || ^6 || ^7 || ^9"
+        "phpstan/phpstan": "^1.2",
+        "phpunit/phpunit": "^8 || ^9"
     }
 }
diff --git a/phpstan.bootstrap.php b/phpstan.bootstrap.php
new file mode 100644
index 0000000..0ac20df
--- /dev/null
+++ b/phpstan.bootstrap.php
@@ -0,0 +1,12 @@
+<?php
+
+// environment initialization
+
+require_once 'lib/init.php';
+
+set_include_path(implode(PATH_SEPARATOR, [
+    'lib/plugins/libkolab/lib',
+    'lib/plugins/libcalendaring',
+    'lib/plugins/libcalendaring/lib',
+    ini_get('include_path'),
+]));
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..d2c6cda
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,22 @@
+parameters:
+    bootstrapFiles:
+        - phpstan.bootstrap.php
+
+    excludePaths:
+        - vendor
+        - lib/plugins
+        - lib/ext/Roundcube
+        - lib/ext/Syncroton
+
+    ignoreErrors:
+        - |Access to an undefined property Syncroton_Model_.*|
+
+    paths:
+        - lib
+        - tests
+
+    level: 2
+
+    scanDirectories:
+        - lib/ext
+