diff --git a/.coveralls.yml b/.coveralls.yml
index 7a18ce2..f6e9ef4 100644
--- a/.coveralls.yml
+++ b/.coveralls.yml
@@ -1 +1 @@
-src_dir: src
+coverage_clover: build/logs/clover.xml
diff --git a/.travis.yml b/.travis.yml
index 6ace717..dbf0eb0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ php:
   - 7.0
   - 7.1
   - 7.2
-  - hhvm
+  - 7.3
 
 matrix:
   include:
@@ -17,7 +17,6 @@ matrix:
     - php: 5.3
     - php: 5.4
     - php: 5.5
-    - php: hhvm
 
 cache:
   directories:
@@ -28,5 +27,5 @@ before_script:
 
 script: vendor/bin/phpunit
 
-after_script:
-  - vendor/bin/coveralls -v
+after_success:
+  - if [ -f vendor/bin/php-coveralls ] ; then travis_retry php vendor/bin/php-coveralls -v; else travis_retry php vendor/bin/coveralls -v; fi
diff --git a/composer.json b/composer.json
index f8a4b3d..d16995f 100644
--- a/composer.json
+++ b/composer.json
@@ -13,12 +13,14 @@
         "php": ">= 5.3.3"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.8.*",
-        "satooshi/php-coveralls": "0.6.*",
-        "symfony/yaml": "2.7.*",
-        "fabpot/php-cs-fixer": "1.10.*"
+        "phpunit/phpunit": "^7.5 || ^4.8",
+        "php-coveralls/php-coveralls": "^2.1 || ^1.1",
+        "symfony/yaml": "^4.2 || ^2.7"
     },
     "autoload": {
         "psr-4": { "Woothee\\": "src/" }
+    },
+    "autoload-dev": {
+        "psr-4": { "Woothee\\": "tests/Woothee/" }
     }
 }
diff --git a/phpunit.xml b/phpunit.xml
index 391b067..8b4b059 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -8,7 +8,6 @@
          convertWarningsToExceptions="true"
          processIsolation="false"
          stopOnFailure="false"
-         syntaxCheck="false"
          bootstrap="tests/bootstrap.php"
 >
     <testsuites>
@@ -18,8 +17,8 @@
     </testsuites>
 
     <filter>
-        <whitelist>
-            <directory>./src/Woothee/</directory>
+        <whitelist processUncoveredFilesFromWhitelist="true">
+            <directory suffix=".php">src/</directory>
         </whitelist>
     </filter>
 
diff --git a/tests/Woothee/Tests/AgentCategory/Os/WindowsTest.php b/tests/Woothee/Tests/AgentCategory/Os/WindowsTest.php
index c46573c..4430516 100644
--- a/tests/Woothee/Tests/AgentCategory/Os/WindowsTest.php
+++ b/tests/Woothee/Tests/AgentCategory/Os/WindowsTest.php
@@ -4,7 +4,7 @@
 
 use Woothee\AgentCategory\Os\Windows;
 
-class WindowsTest extends \PHPUnit_Framework_TestCase
+class WindowsTest extends \Woothee\Tests\TestCase
 {
     public function setUp()
     {
diff --git a/tests/Woothee/Tests/ClassifierTest.php b/tests/Woothee/Tests/ClassifierTest.php
index 9b48bb4..dda700e 100644
--- a/tests/Woothee/Tests/ClassifierTest.php
+++ b/tests/Woothee/Tests/ClassifierTest.php
@@ -5,10 +5,11 @@
 use Symfony\Component\Yaml\Yaml;
 use Woothee\Classifier;
 
-class ClassifierTest extends \PHPUnit_Framework_TestCase
+class ClassifierTest extends TestCase
 {
     public function setUp()
     {
+        parent::setUp();
         $this->classifier = new Classifier();
     }
 
diff --git a/tests/Woothee/Tests/TestCase.php b/tests/Woothee/Tests/TestCase.php
new file mode 100644
index 0000000..fc78e5c
--- /dev/null
+++ b/tests/Woothee/Tests/TestCase.php
@@ -0,0 +1,9 @@
+<?php
+
+namespace Woothee\Tests;
+
+use PHPUnit\Framework\TestCase as PHPUnitTestCase;
+
+abstract class TestCase extends PHPUnitTestCase
+{
+}
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 93da795..9987e9a 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -1,3 +1,5 @@
 <?php
 
 error_reporting(E_ALL);
+
+require_once __DIR__ . '/polyfill.php';
diff --git a/tests/polyfill.php b/tests/polyfill.php
new file mode 100644
index 0000000..c40268e
--- /dev/null
+++ b/tests/polyfill.php
@@ -0,0 +1,14 @@
+<?php
+
+/**
+ * Polyfill for PHPUnit 4.8
+ */
+
+namespace PHPUnit\Framework
+{
+    if (!class_exists('PHPUnit\\Framework\\TestCase')) {
+        abstract class TestCase extends PHPUnit_Framework_TestCase
+        {
+        }
+    }
+}