diff --git a/composer.json b/composer.json
index 3344b85..3393400 100644
--- a/composer.json
+++ b/composer.json
@@ -8,8 +8,10 @@
     "symplify/easy-coding-standard": "9.3.12"
   },
   "require-dev": {
+    "composer/composer": "2.*",
     "jetbrains/phpstorm-attributes": "^1.0",
-    "phpunit/phpunit": "^9.5"
+    "phpunit/phpunit": "^9.5",
+    "symfony/console": "^5.3"
   },
   "authors": [
     {
@@ -29,6 +31,10 @@
   "scripts": {
     "ecs": "./vendor/bin/ecs check",
     "ecsf": "./vendor/bin/ecs check --fix",
-    "test": "./vendor/bin/phpunit tests --colors always"
+    "test": "./vendor/bin/phpunit tests --colors always",
+    "unit": "./vendor/bin/phpunit tests/unit --colors always",
+    "e2e": "./vendor/bin/phpunit tests/codestyle --colors always",
+    "ecs-tmp": "./vendor/bin/ecs check --config ./tests/codestyle/config.php",
+    "ecsf-tmp": "./vendor/bin/ecs check --config ./tests/codestyle/config.php --fix"
   }
 }
diff --git a/ecs.php b/ecs.php
index d0629d2..17db614 100644
--- a/ecs.php
+++ b/ecs.php
@@ -6,7 +6,7 @@
 use Blumilk\Codestyle\Configuration\Defaults\Paths;
 
 $config = new Config(
-    paths: new Paths("examples", "src", "tests")
+    paths: new Paths("src", "tests/unit", "tests/codestyle/CodestyleTest.php")
 );
 
 return $config->config();
diff --git a/examples/arrow_functions.php b/examples/arrow_functions.php
deleted file mode 100644
index 0ac0a35..0000000
--- a/examples/arrow_functions.php
+++ /dev/null
@@ -1,5 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-array_filter([1, 2, 3, 4], fn(int $i): bool => $i % 2 === 0);
diff --git a/tests/codestyle/CodestyleTest.php b/tests/codestyle/CodestyleTest.php
new file mode 100644
index 0000000..0c3d63d
--- /dev/null
+++ b/tests/codestyle/CodestyleTest.php
@@ -0,0 +1,64 @@
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
+class CodestyleTest extends TestCase
+{
+    protected function setUp(): void
+    {
+        $this->clearTempDirectory();
+    }
+
+    protected function tearDown(): void
+    {
+        $this->clearTempDirectory();
+    }
+
+    /**
+     * @throws Exception
+     */
+    public function testFixtures(): void
+    {
+        $fixtures = scandir(__DIR__ . "/fixtures");
+        $fixtures = array_filter($fixtures, fn(string $dir): bool => !str_contains($dir, "."));
+
+        foreach ($fixtures as $fixture) {
+            $this->testFixture($fixture);
+        }
+    }
+
+    /**
+     * @throws Exception
+     */
+    protected function runComposerEcsCommand(bool $fix = false): bool
+    {
+        $command = $fix ? "ecsf-tmp" : "ecs-tmp";
+        $result = 0;
+        $output = null;
+
+        exec("./vendor/bin/composer " . $command, $output, $result);
+
+        return $result === 0;
+    }
+
+    /**
+     * @throws Exception
+     */
+    protected function testFixture(string $name): void
+    {
+        copy(__DIR__ . "/fixtures/${name}/actual.php", __DIR__ . "/tmp/${name}.php");
+        $this->assertFalse($this->runComposerEcsCommand());
+        $this->assertTrue($this->runComposerEcsCommand(true));
+        $this->assertFileEquals(__DIR__ . "/fixtures/${name}/expected.php", __DIR__ . "/tmp/${name}.php");
+    }
+
+    protected function clearTempDirectory(): void
+    {
+        $files = glob(__DIR__ . "/tmp/*.php");
+        foreach ($files as $file) {
+            unlink($file);
+        }
+    }
+}
diff --git a/tests/codestyle/config.php b/tests/codestyle/config.php
new file mode 100644
index 0000000..4f813b4
--- /dev/null
+++ b/tests/codestyle/config.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+use Blumilk\Codestyle\Config;
+use Blumilk\Codestyle\Configuration\Defaults\Paths;
+
+$config = new Config(
+    paths: new Paths("./tests/codestyle/tmp")
+);
+
+return $config->config();
diff --git a/tests/codestyle/fixtures/singleQuotes/actual.php b/tests/codestyle/fixtures/singleQuotes/actual.php
new file mode 100644
index 0000000..1fdae36
--- /dev/null
+++ b/tests/codestyle/fixtures/singleQuotes/actual.php
@@ -0,0 +1,8 @@
+<?php
+
+declare(strict_types=1);
+
+echo 'Test';
+
+$array = [];
+$array['test'] = 'test';
diff --git a/tests/codestyle/fixtures/singleQuotes/expected.php b/tests/codestyle/fixtures/singleQuotes/expected.php
new file mode 100644
index 0000000..9885204
--- /dev/null
+++ b/tests/codestyle/fixtures/singleQuotes/expected.php
@@ -0,0 +1,8 @@
+<?php
+
+declare(strict_types=1);
+
+echo "Test";
+
+$array = [];
+$array["test"] = "test";
diff --git a/tests/codestyle/fixtures/strictTypes/actual.php b/tests/codestyle/fixtures/strictTypes/actual.php
new file mode 100644
index 0000000..724d118
--- /dev/null
+++ b/tests/codestyle/fixtures/strictTypes/actual.php
@@ -0,0 +1,5 @@
+<?php
+
+class StrictTypesExample
+{
+}
diff --git a/tests/codestyle/fixtures/strictTypes/expected.php b/tests/codestyle/fixtures/strictTypes/expected.php
new file mode 100644
index 0000000..299d16a
--- /dev/null
+++ b/tests/codestyle/fixtures/strictTypes/expected.php
@@ -0,0 +1,7 @@
+<?php
+
+declare(strict_types=1);
+
+class StrictTypesExample
+{
+}
diff --git a/tests/codestyle/fixtures/unionTypes/actual.php b/tests/codestyle/fixtures/unionTypes/actual.php
new file mode 100644
index 0000000..696f903
--- /dev/null
+++ b/tests/codestyle/fixtures/unionTypes/actual.php
@@ -0,0 +1,11 @@
+<?php
+
+class UnionTypesExample
+{
+    public int|string $something;
+
+    public function do(): void {
+        $i = 1+1;
+        json_encode([$i], JSON_THROW_ON_ERROR|JSON_UNESCAPED_SLASHES);
+    }
+}
diff --git a/examples/union_types.php b/tests/codestyle/fixtures/unionTypes/expected.php
similarity index 77%
rename from examples/union_types.php
rename to tests/codestyle/fixtures/unionTypes/expected.php
index f8d4e59..d0a87ec 100644
--- a/examples/union_types.php
+++ b/tests/codestyle/fixtures/unionTypes/expected.php
@@ -2,13 +2,10 @@
 
 declare(strict_types=1);
 
-class Whatever
+class UnionTypesExample
 {
     public int|string $something;
 
-    /**
-     * @throws JsonException
-     */
     public function do(): void
     {
         $i = 1 + 1;
diff --git a/tests/codestyle/tmp/.gitignore b/tests/codestyle/tmp/.gitignore
new file mode 100644
index 0000000..d6b7ef3
--- /dev/null
+++ b/tests/codestyle/tmp/.gitignore
@@ -0,0 +1,2 @@
+*
+!.gitignore
diff --git a/tests/AdditionalRulesConfigurationTest.php b/tests/unit/AdditionalRulesConfigurationTest.php
similarity index 100%
rename from tests/AdditionalRulesConfigurationTest.php
rename to tests/unit/AdditionalRulesConfigurationTest.php
diff --git a/tests/LaravelPathsConfigurationTest.php b/tests/unit/LaravelPathsConfigurationTest.php
similarity index 100%
rename from tests/LaravelPathsConfigurationTest.php
rename to tests/unit/LaravelPathsConfigurationTest.php
diff --git a/tests/PathsConfigurationTest.php b/tests/unit/PathsConfigurationTest.php
similarity index 100%
rename from tests/PathsConfigurationTest.php
rename to tests/unit/PathsConfigurationTest.php
diff --git a/tests/SetsConfigurationTest.php b/tests/unit/SetsConfigurationTest.php
similarity index 100%
rename from tests/SetsConfigurationTest.php
rename to tests/unit/SetsConfigurationTest.php
diff --git a/tests/SkippedRulesConfigurationTest.php b/tests/unit/SkippedRulesConfigurationTest.php
similarity index 100%
rename from tests/SkippedRulesConfigurationTest.php
rename to tests/unit/SkippedRulesConfigurationTest.php