diff --git a/ .github/workflows/test.yml b/ .github/workflows/test.yml
new file mode 100644
index 0000000..c6243ef
--- /dev/null
+++ b/ .github/workflows/test.yml	
@@ -0,0 +1,33 @@
+name: Tests with PHPUnit
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Validate composer.json and composer.lock
+      run: composer validate --strict
+
+    - name: Cache Composer packages
+      id: composer-cache
+      uses: actions/cache@v2
+      with:
+        path: vendor
+        key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-php-
+
+    - name: Install dependencies
+      run: composer install --prefer-dist --no-progress
+
+    - name: Run test suite
+      run: composer run-script test
diff --git a/.travis.yml b/.travis.yml
index 1c5e371..b6273b1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,13 +1,13 @@
 language: php
 
 php:
-  - 7.1
-  - 7.2
   - 7.3
+  - 7.4
+  - 8.0
 
 sudo: false
 
-dist: trusty
+dist: bionic
 
 before_script:
   - composer self-update
diff --git a/composer.json b/composer.json
index d1c56b9..c1ee65d 100644
--- a/composer.json
+++ b/composer.json
@@ -16,17 +16,17 @@
         }
     ],
     "require": {
-        "php": "^5.6 || ^7.0",
+        "php": ">=7.3",
         "psr/http-message": "^1.0",
-        "guzzlehttp/guzzle": "^6.0",
-        "laminas/laminas-diactoros": "^2.0",
+        "guzzlehttp/guzzle": "^7.3",
+        "laminas/laminas-diactoros": "^2.6",
         "relay/relay": "^1.0",
-        "laminas/laminas-httphandlerrunner": "^1.1"
+        "laminas/laminas-httphandlerrunner": "^2.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^5.0|^6.0|^7.0",
-        "php-coveralls/php-coveralls": "^2.0",
-        "mockery/mockery": "^1.1"
+        "phpunit/phpunit": "^9.0",
+        "php-coveralls/php-coveralls": "^2.4",
+        "mockery/mockery": "^1.4"
     },
     "autoload": {
         "psr-4": {
@@ -37,5 +37,8 @@
         "psr-4": {
             "Proxy\\": "tests"
         }
+    },
+    "scripts": {
+        "test": "vendor/bin/phpunit"
     }
 }
diff --git a/phpunit.xml b/phpunit.xml
index 8034fdf..da13ea1 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit backupGlobals="false"
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd"
+         backupGlobals="false"
          backupStaticAttributes="false"
          bootstrap="vendor/autoload.php"
          colors="true"
@@ -9,14 +11,14 @@
          processIsolation="false"
          stopOnFailure="true"
 >
-    <testsuites>
-        <testsuite name="PHPProxy Test Suite">
-            <directory>tests/Proxy/</directory>
-        </testsuite>
-    </testsuites>
-    <filter>
-        <whitelist>
-            <directory suffix=".php">./src</directory>
-        </whitelist>
-    </filter>
+  <coverage>
+    <include>
+      <directory suffix=".php">./src</directory>
+    </include>
+  </coverage>
+  <testsuites>
+    <testsuite name="PHPProxy Test Suite">
+      <directory>tests/Proxy/</directory>
+    </testsuite>
+  </testsuites>
 </phpunit>
diff --git a/tests/Proxy/Adapter/Dummy/DummyAdapterTest.php b/tests/Proxy/Adapter/Dummy/DummyAdapterTest.php
index 62a869b..a4a52cc 100644
--- a/tests/Proxy/Adapter/Dummy/DummyAdapterTest.php
+++ b/tests/Proxy/Adapter/Dummy/DummyAdapterTest.php
@@ -13,7 +13,7 @@ class DummyAdapterTest extends TestCase
      */
     private $adapter;
 
-    public function setUp()
+    public function setUp(): void
     {
         $this->adapter = new DummyAdapter();
     }
diff --git a/tests/Proxy/Adapter/Guzzle/GuzzleAdapterTest.php b/tests/Proxy/Adapter/Guzzle/GuzzleAdapterTest.php
index 9f9940b..0bdc338 100644
--- a/tests/Proxy/Adapter/Guzzle/GuzzleAdapterTest.php
+++ b/tests/Proxy/Adapter/Guzzle/GuzzleAdapterTest.php
@@ -32,7 +32,7 @@ class GuzzleAdapterTest extends TestCase
      */
     private $body = 'Totally awesome response body';
 
-    public function setUp()
+    public function setUp(): void
     {
         $mock = new MockHandler([
             $this->createResponse(),
diff --git a/tests/Proxy/Filter/RemoveEncodingFilterTest.php b/tests/Proxy/Filter/RemoveEncodingFilterTest.php
index c407695..7a397ca 100644
--- a/tests/Proxy/Filter/RemoveEncodingFilterTest.php
+++ b/tests/Proxy/Filter/RemoveEncodingFilterTest.php
@@ -13,7 +13,7 @@ class RemoveEncodingFilterTest extends TestCase
      */
     private $filter;
 
-    public function setUp()
+    public function setUp(): void
     {
         $this->filter = new RemoveEncodingFilter();
     }
diff --git a/tests/Proxy/Filter/RemoveLocationFilterTest.php b/tests/Proxy/Filter/RemoveLocationFilterTest.php
index ea96bde..a9a4971 100644
--- a/tests/Proxy/Filter/RemoveLocationFilterTest.php
+++ b/tests/Proxy/Filter/RemoveLocationFilterTest.php
@@ -13,7 +13,7 @@ class RemoveLocationFilterTest extends TestCase
      */
     private $filter;
 
-    public function setUp()
+    public function setUp(): void
     {
         $this->filter = new RemoveLocationFilter();
     }
diff --git a/tests/Proxy/Filter/RewriteLocationFilterTest.php b/tests/Proxy/Filter/RewriteLocationFilterTest.php
index 3bcc5f4..c67b71e 100644
--- a/tests/Proxy/Filter/RewriteLocationFilterTest.php
+++ b/tests/Proxy/Filter/RewriteLocationFilterTest.php
@@ -11,7 +11,7 @@ class RewriteLocationFilterTest extends TestCase
      */
     private $filter;
 
-    public function setUp()
+    public function setUp(): void
     {
         $this->filter = new RewriteLocationFilter();
     }
diff --git a/tests/Proxy/ProxyTest.php b/tests/Proxy/ProxyTest.php
index b46017e..851d26b 100644
--- a/tests/Proxy/ProxyTest.php
+++ b/tests/Proxy/ProxyTest.php
@@ -17,17 +17,17 @@ class ProxyTest extends TestCase
      */
     private $proxy;
 
-    public function setUp()
+    public function setUp(): void
     {
         $this->proxy = new Proxy(new DummyAdapter());
     }
 
     /**
      * @test
-     * @expectedException UnexpectedValueException
      */
     public function to_throws_exception_if_no_request_is_given()
     {
+        $this->expectException('UnexpectedValueException');
         $this->proxy->to('http://www.example.com');
     }
 
@@ -48,8 +48,7 @@ public function to_applies_filters()
     {
         $applied = false;
 
-        $this->proxy->forward(ServerRequestFactory::fromGlobals())->filter(function ($request, $response) use (&$applied
-        ) {
+        $this->proxy->forward(ServerRequestFactory::fromGlobals())->filter(function ($request, $response) use (&$applied) {
             $applied = true;
         })->to('http://www.example.com');