diff --git a/.travis.yml b/.travis.yml
index 36245cb..e145c58 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,9 @@
 language: php
 dist: trusty
 php:
+  - "7.4"
+  - "7.3"
+  - "7.2"
   - "7.1"
   - "7.0"
   - "5.6"
diff --git a/composer.json b/composer.json
index db5d1c0..bb7dcd1 100644
--- a/composer.json
+++ b/composer.json
@@ -1,20 +1,28 @@
 {
-    "name": "mikehaertl/php-shellcommand",
-    "description": "An object oriented interface to shell commands",
-    "keywords": ["shell"],
-    "license": "MIT",
-    "authors": [
-        {
-            "name": "Michael Härtl",
-            "email": "haertl.mike@gmail.com"
-        }
-    ],
-    "require": {
-	"php": ">= 5.4.0"
-    },
-    "autoload": {
-        "psr-4": {
-            "mikehaertl\\shellcommand\\": "src/"
-        }
+  "name": "mikehaertl/php-shellcommand",
+  "description": "An object oriented interface to shell commands",
+  "keywords": ["shell"],
+  "license": "MIT",
+  "authors": [
+    {
+      "name": "Michael Härtl",
+      "email": "haertl.mike@gmail.com"
     }
+  ],
+  "require": {
+    "php": ">= 5.4.0"
+  },
+  "require-dev": {
+      "phpunit/phpunit": ">4.0 <8"
+  },
+  "autoload": {
+    "psr-4": {
+      "mikehaertl\\shellcommand\\": "src/"
+    }
+  },
+  "autoload-dev": {
+      "psr-4": {
+          "tests\\": "tests"
+      }
+  }
 }
diff --git a/tests/BlockingCommandTest.php b/tests/BlockingCommandTest.php
index 838c98c..538623d 100644
--- a/tests/BlockingCommandTest.php
+++ b/tests/BlockingCommandTest.php
@@ -1,7 +1,10 @@
 <?php
+namespace tests;
+
+use PHPUnit\Framework\TestCase;
 use mikehaertl\shellcommand\Command;
 
-class BlockingCommandTest extends \PHPUnit\Framework\TestCase
+class BlockingCommandTest extends TestCase
 {
     public function setUp()
     {
diff --git a/tests/CommandTest.php b/tests/CommandTest.php
index 281e932..9cf72fa 100644
--- a/tests/CommandTest.php
+++ b/tests/CommandTest.php
@@ -1,7 +1,10 @@
 <?php
+namespace tests;
+
+use PHPUnit\Framework\TestCase;
 use mikehaertl\shellcommand\Command;
 
-class CommandTest extends \PHPUnit\Framework\TestCase
+class CommandTest extends TestCase
 {
     public function setUp()
     {