diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 7cbb785..1e2eda1 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -11,7 +11,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [7.4]
+        php: [7.4, 8.1, 8.2, 8.3]
 
     steps:
       - uses: actions/checkout@v4
@@ -25,4 +25,8 @@ jobs:
 
       - run: composer install --no-interaction
 
-      - run: vendor/bin/phpunit
+      - name: PhpUnit
+        run: |
+          set -x
+          php --version
+          vendor/bin/phpunit
diff --git a/composer.json b/composer.json
index d7b88fa..e7a30bf 100644
--- a/composer.json
+++ b/composer.json
@@ -14,6 +14,6 @@
     "psr-4": { "Donquixote\\Cellbrush\\": "src/" }
   },
   "require-dev": {
-    "phpunit/phpunit": "^5"
+    "phpunit/phpunit": "^9.6"
   }
 }
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 986eaeb..96bf735 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,14 +1,12 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
-<phpunit backupGlobals="false"
-         backupStaticAttributes="false"
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="vendor/phpunit/phpunit/phpunit.xsd"
          colors="true"
-         convertErrorsToExceptions="true"
-         convertNoticesToExceptions="true"
-         convertWarningsToExceptions="true"
-         processIsolation="false"
-         stopOnFailure="false"
-         syntaxCheck="false"
+         convertDeprecationsToExceptions="true"
+         failOnIncomplete="true"
+         failOnRisky="true"
+         failOnSkipped="true"
+         failOnWarning="true"
          bootstrap="vendor/autoload.php"
 >
   <testsuites>
diff --git a/tests/src/AttributesMapTest.php b/tests/src/AttributesMapTest.php
index dbc76bd..e17439c 100644
--- a/tests/src/AttributesMapTest.php
+++ b/tests/src/AttributesMapTest.php
@@ -3,8 +3,9 @@
 namespace Donquixote\Cellbrush\Tests;
 
 use Donquixote\Cellbrush\Html\Multiple\StaticAttributesMap;
+use PHPUnit\Framework\TestCase;
 
-class AttributesMapTest extends \PHPUnit_Framework_TestCase {
+class AttributesMapTest extends TestCase {
 
   function testMerge() {
     $a = StaticAttributesMap::create(
diff --git a/tests/src/CellMatrixTest.php b/tests/src/CellMatrixTest.php
index 1b7cafa..25d7d64 100644
--- a/tests/src/CellMatrixTest.php
+++ b/tests/src/CellMatrixTest.php
@@ -4,8 +4,9 @@
 
 use Donquixote\Cellbrush\Cell\Cell;
 use Donquixote\Cellbrush\Matrix\CellMatrix;
+use PHPUnit\Framework\TestCase;
 
-class CellMatrixTest extends \PHPUnit_Framework_TestCase {
+class CellMatrixTest extends TestCase {
 
   function testRowspanSimple() {
     $cellMatrix = CellMatrix::create(2, 1);
diff --git a/tests/src/CellbrushTest.php b/tests/src/CellbrushTest.php
index 1fe35bb..7e23b5b 100644
--- a/tests/src/CellbrushTest.php
+++ b/tests/src/CellbrushTest.php
@@ -3,8 +3,9 @@
 namespace Donquixote\Cellbrush\Tests;
 
 use Donquixote\Cellbrush\Table\Table;
+use PHPUnit\Framework\TestCase;
 
-class CellbrushTest extends \PHPUnit_Framework_TestCase {
+class CellbrushTest extends TestCase {
 
   function testRegularTable() {
 
diff --git a/tests/src/HierarchyTest.php b/tests/src/HierarchyTest.php
index 8a3ce32..56b5747 100644
--- a/tests/src/HierarchyTest.php
+++ b/tests/src/HierarchyTest.php
@@ -3,8 +3,9 @@
 namespace Donquixote\Cellbrush\Tests;
 
 use Donquixote\Cellbrush\Axis\DynamicAxis;
+use PHPUnit\Framework\TestCase;
 
-class HierarchyTest extends \PHPUnit_Framework_TestCase {
+class HierarchyTest extends TestCase {
 
   function testFlat() {
     $hierarchy = new DynamicAxis();
diff --git a/tests/src/TableSectionTest.php b/tests/src/TableSectionTest.php
index 7fc71b7..234bd92 100644
--- a/tests/src/TableSectionTest.php
+++ b/tests/src/TableSectionTest.php
@@ -5,8 +5,9 @@
 use Donquixote\Cellbrush\Axis\DynamicAxis;
 use Donquixote\Cellbrush\Html\Multiple\StaticAttributesMap;
 use Donquixote\Cellbrush\TSection\TableSection;
+use PHPUnit\Framework\TestCase;
 
-class TableSectionTest extends \PHPUnit_Framework_TestCase {
+class TableSectionTest extends TestCase {
 
   function testRegularTable() {
     $columns = new DynamicAxis();