diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
new file mode 100644
index 0000000..3bd4e08
--- /dev/null
+++ b/.github/workflows/main.yaml
@@ -0,0 +1,49 @@
+name: Main
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+      - master
+      - release/**
+  pull_request:
+    branches:
+      - main
+      - master
+      - release/**
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  run:
+    runs-on: ${{ matrix.operating-system }}
+    strategy:
+      matrix:
+        operating-system: ['ubuntu-latest', 'macos-latest'] #, 'windows-latest']
+        php-versions: ['5.6', '7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3']
+    steps:
+    - name: Get source code
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: ${{ matrix.php-versions }}
+        coverage: none
+        ini-values: post_max_size=256M, max_execution_time=180
+    - run: sudo pear list
+    - run: sudo pear channel-update pear.php.net
+    - run: sudo pear upgrade --force pear/pear
+    - run: sudo pear list
+    - run: sudo pear install --force package.xml
+    - run: sudo pear list
+    - run: sudo pear package
+    - run: sudo pear package-validate
+    - run: sudo pear install --force *.tgz
+    - run: sudo pear list
+    - run: composer install
+    - run: ./vendor/bin/phpunit tests
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 083af02..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,26 +0,0 @@
-language: php
-sudo: false
-php:
-  - 5.6
-  - 7.0
-  - 7.1
-  - 7.2
-  - 7.3
-  - 7.4
-# Disable xdebug for PHP >= 7.3
-# https://stackoverflow.com/questions/65172031/vendor-bin-phpunit-exited-with-2
-before_script:
-  - phpenv config-rm xdebug.ini
-script:
-  - pear list
-  - pear channel-update pear.php.net
-  - pear upgrade --force pear/pear
-  - pear list
-  - pear install --force package.xml
-  - pear list
-  - pear package
-  - pear package-validate
-  - pear install --force *.tgz
-  - pear list
-  - composer install
-  - ./vendor/bin/phpunit -c phpunit.xml.dist
diff --git a/composer.json b/composer.json
index fd97b87..4f5ded2 100644
--- a/composer.json
+++ b/composer.json
@@ -47,6 +47,6 @@
         "pear/pear-core-minimal": "^1.10.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "^4"
+        "yoast/phpunit-polyfills": "^2.0"
     }
 }
diff --git a/package.xml b/package.xml
index 970e7dd..ce236f9 100644
--- a/package.xml
+++ b/package.xml
@@ -60,7 +60,6 @@ There are two classes to use for templating. HTML_Template_IT is used for basic
    <file name="HTML/Template/IT.php" role="php" />
    <file name="HTML/Template/ITX.php" role="php" />
    <file name="HTML/Template/IT_Error.php" role="php" />
-   <file name="tests/AllTests.php" role="test" />
    <file name="tests/ITTest.php" role="test" />
    <file name="tests/ITXTest.php" role="test" />
    <file name="tests/templates/addblock.html" role="test" />
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
deleted file mode 100644
index 31c5c11..0000000
--- a/phpunit.xml.dist
+++ /dev/null
@@ -1,29 +0,0 @@
-<phpunit bootstrap="vendor/autoload.php"
-         cacheTokens="false"
-         colors="true"
-         convertErrorsToExceptions="true"
-         convertNoticesToExceptions="true"
-         convertWarningsToExceptions="true"
-         stopOnError="false"
-         stopOnFailure="false"
-         stopOnIncomplete="false"
-         stopOnSkipped="false">
-
-    <testsuites>
-        <testsuite name="Test Suite">
-            <directory suffix=".php">tests/</directory>
-        </testsuite>
-    </testsuites>
-
-    <filter>
-        <whitelist>
-            <directory suffix=".php">HTML/</directory>
-        </whitelist>
-    </filter>
-
-    <logging>
-        <log type="coverage-clover" target="build/logs/clover.xml"/>
-        <log type="coverage-html" target="build/coverage/"/>
-    </logging>
-
-</phpunit>
diff --git a/tests/AllTests.php b/tests/AllTests.php
deleted file mode 100644
index 0059556..0000000
--- a/tests/AllTests.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-if (!defined('PHPUnit_MAIN_METHOD')) {
-    define('PHPUnit_MAIN_METHOD', 'HTML_Template_IT_AllTests::main');
-}
-
-
-
-require_once 'ITTest.php';
-require_once 'ITXTest.php';
-
-
-class HTML_Template_IT_AllTests
-{
-    public static function main()
-    {
-
-        PHPUnit_TextUI_TestRunner::run(self::suite());
-    }
-
-    public static function suite()
-    {
-        $suite = new PHPUnit_Framework_TestSuite('HTML_Template_IT tests');
-
-        $suite->addTestSuite('ITTest');
-        $suite->addTestSuite('ITXTest');
-
-        return $suite;
-    }
-}
-
-if (PHPUnit_MAIN_METHOD == 'HTML_Template_IT_AllTests::main') {
-    HTML_Template_IT_AllTests::main();
-}
-?>
diff --git a/tests/ITTest.php b/tests/ITTest.php
index ac95752..2e8616f 100644
--- a/tests/ITTest.php
+++ b/tests/ITTest.php
@@ -1,7 +1,15 @@
 <?php
+
+// As we want to run on PHP < 7.1,
+// we can't use return type declaration in fixtures.
+// Therefore we use PHPUnitPolyFills snakecase fixtures set_up/tear_down
+// instead of setUp/tearDown.
+// See https://github.com/Yoast/PHPUnit-Polyfills?tab=readme-ov-file#option-1-yoastphpunitpolyfillstestcasestestcase
+use Yoast\PHPUnitPolyfills\TestCases\TestCase;
+
 require_once 'HTML/Template/IT.php';
 
-class ITTest extends PHPUnit_Framework_TestCase
+class ITTest extends Yoast\PHPUnitPolyfills\TestCases\TestCase
 {
    /**
     * An HTML_Template_IT object
@@ -9,12 +17,12 @@ class ITTest extends PHPUnit_Framework_TestCase
     */
     var $tpl;
 
-    function setUp()
+    protected function set_up()
     {
         $this->tpl = new HTML_Template_IT(dirname(__FILE__) . '/templates');
     }
 
-    function tearDown()
+    protected function tear_down()
     {
         unset($this->tpl);
     }
diff --git a/tests/ITXTest.php b/tests/ITXTest.php
index 87f19c2..f5a728c 100644
--- a/tests/ITXTest.php
+++ b/tests/ITXTest.php
@@ -23,7 +23,7 @@ static function _numberFormatCallback($float, $decimals)
 
 class ITXTest extends ITTest
 {
-    function setUp()
+    function set_up()
     {
         $this->tpl = new HTML_Template_ITX(dirname(__FILE__) . '/templates');
     }