diff --git a/.gitignore b/.gitignore
index 7ddbf75..a9127cb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,7 @@
 /vendor/
+/phpdoc/
 
 /.idea/
+/.phpdoc/
+/.phpunit.result.cache
+/.php_cs.cache
diff --git a/.php_cs.dist b/.php_cs.dist
new file mode 100644
index 0000000..ba2fb31
--- /dev/null
+++ b/.php_cs.dist
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+$finder = PhpCsFixer\Finder::create()
+    ->exclude('vendor')
+    ->in(__DIR__)
+;
+
+$customRules = [
+  '@Symfony' => true,
+  'array_syntax' => ['syntax' => 'short'],
+  'concat_space' => ['spacing' => 'one'],
+  'increment_style' => ['style' => 'post'],
+  'declare_strict_types' => true,
+  'phpdoc_summary' => false,
+];
+
+$psr12Rules = [
+  '@PSR2' => true,
+  'blank_line_after_opening_tag' => true,
+  'braces' => ['allow_single_line_closure' => true],
+  'compact_nullable_typehint' => true,
+  'concat_space' => ['spacing' => 'one'],
+  'declare_equal_normalize' => ['space' => 'none'],
+  'function_typehint_space' => true,
+  'new_with_braces' => true,
+  'method_argument_space' => ['on_multiline' => 'ensure_fully_multiline'],
+  'no_empty_statement' => true,
+  'no_leading_import_slash' => true,
+  'no_leading_namespace_whitespace' => true,
+  'no_whitespace_in_blank_line' => true,
+  'return_type_declaration' => ['space_before' => 'none'],
+  'single_trait_insert_per_statement' => true,
+];
+
+return PhpCsFixer\Config::create()
+  ->setRules($customRules + $psr12Rules)
+  ->setFinder($finder)
+;
diff --git a/composer.json b/composer.json
index af45f3e..aecf3a9 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
     "require": {
         "php": "~7.4",
         "google/apiclient": "^2.8",
-        "wizaplace/php-etl": "^1.2"
+        "wizaplace/php-etl": "<=1.2.1"
     },
     "autoload": {
         "psr-4": {
diff --git a/composer.lock b/composer.lock
index 4964c13..c7709b9 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "7818bb11934e586dad6507ed2de7c408",
+    "content-hash": "5c9e6eed8e4da83c4c91a9c8701e1d00",
     "packages": [
         {
             "name": "firebase/php-jwt",
diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index d4dcf38..75d6aa2 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -6,4 +6,5 @@
     <rule ref="PSR12"/>
     <rule ref="Generic.PHP.Syntax"/>
     <file>src</file>
+    <file>tests</file>
 </ruleset>
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 5fc0feb..48d2fbd 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -3,28 +3,13 @@ parameters:
     level: 6
     paths:
         - src
+        - tests
     checkMissingIterableValueType: false
     checkGenericClassInNonGenericObjectType: false
     ignoreErrors:
         -
-            message: '~^Variable method call on ~'
-            path: src/Database/Query.php
-
+            message: '~^Call to an undefined method Prophecy\\Prophecy\\ObjectProphecy::~'
+            path: tests/Extractors/GoogleAnalyticsTest.php
         -
-            message: '~^Variable method call on ~'
-            path: src/Database/Statement.php
-
-        -
-            message: '~^Variable method call on ~'
-            path: src/Etl.php
-
-        -
-            message: '~^Variable property access on ~'
-            path: src/Row.php
-
-        -
-            message: '~^Variable property access on ~'
-            path: src/Step.php
-        -
-            message: '~^Dynamic call to static method XMLReader::open\(\)\.~'
-            path: src/Extractors\Xml.php
+            message: '~^Access to an undefined property Prophecy\\Prophecy\\ObjectProphecy::~'
+            path: tests/Extractors/GoogleAnalyticsTest.php
diff --git a/src/Extractors/GoogleAnalytics.php b/src/Extractors/GoogleAnalytics.php
index 6a72573..2bb862f 100644
--- a/src/Extractors/GoogleAnalytics.php
+++ b/src/Extractors/GoogleAnalytics.php
@@ -53,7 +53,14 @@
  *
  * ### Input
  *
- * {@see GoogleAnalytics::$input}
+ * By default, the input is all the web properties the Google client has access to.
+ * However, an array of property names may be specified to limit the extraction to
+ * a smaller set of properties. (In the example below, property names correspond to
+ * the web site name, but that is not necessarily true for all GA users.)
+ *
+ * ```php
+ * $input = ['www.example.com', 'demo.example.com'];
+ * ```
  *
  * ### Options
  *  - Dimensions (required) {@see GoogleAnalytics::$dimensions}
@@ -66,24 +73,8 @@ class GoogleAnalytics extends Extractor
 {
     private const REPORT_PAGE_SIZE = 1000;
 
-    /**
-     * The input source.
-     *
-     * By default, the input is all the web properties the Google client has access to.
-     * However, an array of property names may be specified to limit the extraction to
-     * a smaller set of properties. (In the example below, property names correspond to
-     * the web site name, but that is not necessarily true for all GA users.)
-     *
-     * ```php
-     * $input = ['www.example.com', 'demo.example.com'];
-     * ```
-     *
-     * @var string[]
-     */
-    protected array $input = [];
-
-    /** @var string[] */
-    protected array $availableOptions = ['startDate', 'endDate', 'views', 'dimensions', 'metrics'];
+    /** @var array */
+    protected $availableOptions = ['startDate', 'endDate', 'views', 'dimensions', 'metrics'];
 
     /**
      * The dimension or dimensions used to group analytics data (frequently "ga:date").
@@ -203,9 +194,6 @@ public function extract(): \Generator
 
             $request = $this->reportRequest($profileSummary->getId());
             $reports = $this->reportingService->reports->batchGet($request);
-            if (empty($reports)) {
-                print_r($request);
-            }
 
             /** @var \Google_Service_AnalyticsReporting_Report $report */
             foreach ($reports as $report) {
diff --git a/tests/Extractors/GoogleAnalyticsTest.php b/tests/Extractors/GoogleAnalyticsTest.php
index 553cb41..4295016 100644
--- a/tests/Extractors/GoogleAnalyticsTest.php
+++ b/tests/Extractors/GoogleAnalyticsTest.php
@@ -11,32 +11,29 @@
 
 namespace PhpEtl\GoogleAnalytics\Tests\Extractors;
 
-use PhpEtl\GoogleAnalytics\Tests\TestCase;
 use PhpEtl\GoogleAnalytics\Extractors\GoogleAnalytics;
+use PhpEtl\GoogleAnalytics\Tests\TestCase;
 use Wizaplace\Etl\Row;
 
 /**
- * Class GoogleAnalyticsTest
- *
- * @package Tests\Extractors
+ * Tests GoogleAnalytics.
  */
 class GoogleAnalyticsTest extends TestCase
 {
-
     protected array $input = [];
 
     protected array $options = [
         'startDate' => '2010-11-11',
         'dimensions' => ['ga:date'],
-        'metrics' => [['name' => 'ga:pageviews', 'type' => 'INTEGER']]
+        'metrics' => [['name' => 'ga:pageviews', 'type' => 'INTEGER']],
     ];
 
     /** @test */
-    public function defaultOptions()
+    public function defaultOptions(): void
     {
         $expected = [
-            new Row(['id' => 1, 'name' => 'John Doe', 'email' => 'johndoe@email.com']),
-            new Row(['id' => 2, 'name' => 'Jane Doe', 'email' => 'janedoe@email.com']),
+            new Row(['id' => '1', 'name' => 'John Doe', 'email' => 'johndoe@email.com']),
+            new Row(['id' => '2', 'name' => 'Jane Doe', 'email' => 'janedoe@email.com']),
         ];
 
         $profile = $this->prophesize(\Google_Service_Analytics_ProfileSummary::class);
diff --git a/tests/TestCase.php b/tests/TestCase.php
index adb974e..ab7cfb9 100644
--- a/tests/TestCase.php
+++ b/tests/TestCase.php
@@ -16,31 +16,28 @@
 use Wizaplace\Etl\Transformers\Transformer;
 
 /**
- * Class TestCase
- *
- * @package Tests
+ * Base class for PHP-ETL tests.
  */
 abstract class TestCase extends BaseTestCase
 {
-
     /**
-     * @param $step
-     * @param $data
+     * @param Transformer|Loader $step
+     * @param array              $data
      */
-    protected function execute($step, $data)
+    protected function execute($step, $data): void
     {
+        $step->initialize();
+
         if ($step instanceof Transformer) {
-            $method = 'transform';
+            foreach ($data as $row) {
+                $step->transform($row);
+            }
         }
 
         if ($step instanceof Loader) {
-            $method = 'load';
-        }
-
-        $step->initialize();
-
-        foreach ($data as $row) {
-            $step->$method($row);
+            foreach ($data as $row) {
+                $step->load($row);
+            }
         }
 
         $step->finalize();