diff --git a/.github/workflows/continuous_integration.yml b/.github/workflows/continuous_integration.yml
index b489d50..53a4c5a 100644
--- a/.github/workflows/continuous_integration.yml
+++ b/.github/workflows/continuous_integration.yml
@@ -17,7 +17,7 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@0f7f1d08e3e32076e51cae65eb0b0c871405b16e
         with:
-          php-version: '8.3'
+          php-version: '8.4'
           tools: composer
 
       - name: Get Composer Cache Directory
diff --git a/Dockerfile b/Dockerfile
index 73bdb44..92ecf20 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM php:8.3.10-cli-alpine3.20 AS build
+FROM php:8.4.10-cli-alpine3.22 AS build
 
 RUN apk add --no-cache ca-certificates curl jo zip unzip
 
@@ -9,7 +9,7 @@ RUN curl -L -o install-php-extensions \
     && chmod +x install-php-extensions \
     && install-php-extensions ds-^1@stable intl
 
-COPY --from=composer:2.7.7 /usr/bin/composer /usr/local/bin/composer
+COPY --from=composer:2.8.9 /usr/bin/composer /usr/local/bin/composer
 
 WORKDIR /opt/test-runner
 COPY . .
@@ -23,7 +23,7 @@ RUN mv "$PHP_INI_DIR/php.ini-production" "$PHP_INI_DIR/php.ini" \
         COMPOSER_ALLOW_SUPERUSER=1 \
         composer install --no-cache --no-dev --no-interaction --no-progress
 
-FROM php:8.3.10-cli-alpine3.20 AS runtime
+FROM php:8.4.10-cli-alpine3.22 AS runtime
 
 COPY --from=build /usr/bin/jo /usr/bin/jo
 COPY --from=build /usr/local/lib/php/extensions /usr/local/lib/php/extensions
diff --git a/README.md b/README.md
index 92fcea0..343166a 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ It meets the complete spec for testing all exercises.
 ### Docker image
 
 The website uses isolated Docker images to run untrusted code in a sandbox.
-The image provided by this repository consists of PHP 8.3.10 (PHPUnit 10).
+The image provided by this repository consists of PHP 8.4.10 (PHPUnit 11).
 All final assets are built into the image, because the image does not have network access once in use.
 
 Includes PHP extensions: ds, intl
diff --git a/composer.json b/composer.json
index b4d77ca..9b0be5e 100644
--- a/composer.json
+++ b/composer.json
@@ -8,13 +8,13 @@
         }
     },
     "require": {
-        "php": "^8.3",
-        "phpunit/phpunit": "^10.5.29"
+        "php": "^8.4",
+        "phpunit/phpunit": "^11.5.26"
     },
     "require-dev": {
-        "phpstan/phpstan": "^2.1",
-        "slevomat/coding-standard": "^8.14.1",
-        "squizlabs/php_codesniffer": "^3.12"
+        "phpstan/phpstan": "^2.1.17",
+        "slevomat/coding-standard": "^8.19.1",
+        "squizlabs/php_codesniffer": "^3.13.2"
     },
     "scripts": {
         "phpstan": "phpstan analyse --configuration phpstan.neon --memory-limit=2G",
diff --git a/tests/all-fail/HelloWorld.php b/tests/all-fail/HelloWorld.php
new file mode 100644
index 0000000..2e09437
--- /dev/null
+++ b/tests/all-fail/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return "Goodbye, Mars!";
+}
diff --git a/tests/all-fail/HelloWorldTest.php b/tests/all-fail/HelloWorldTest.php
new file mode 100644
index 0000000..db4338e
--- /dev/null
+++ b/tests/all-fail/HelloWorldTest.php
@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    public function testHelloWorldOne(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+
+    public function testHelloWorldTwo(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+
+    public function testHelloWorldThree(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/all-fail/expected_results.json b/tests/all-fail/expected_results.json
new file mode 100644
index 0000000..4192004
--- /dev/null
+++ b/tests/all-fail/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"fail","tests":[{"name":"Hello world one","status":"fail","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","message":"HelloWorldTest::testHelloWorldOne\nFailed asserting that two strings are equal.\n--- Expected\n+++ Actual\n@@ @@\n-'Hello, World!'\n+'Goodbye, Mars!'\n\nHelloWorldTest.php:14"},{"name":"Hello world two","status":"fail","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","message":"HelloWorldTest::testHelloWorldTwo\nFailed asserting that two strings are equal.\n--- Expected\n+++ Actual\n@@ @@\n-'Hello, World!'\n+'Goodbye, Mars!'\n\nHelloWorldTest.php:19"},{"name":"Hello world three","status":"fail","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","message":"HelloWorldTest::testHelloWorldThree\nFailed asserting that two strings are equal.\n--- Expected\n+++ Actual\n@@ @@\n-'Hello, World!'\n+'Goodbye, Mars!'\n\nHelloWorldTest.php:24"}]}
diff --git a/tests/dataProvider-error/GigasecondTest.php b/tests/dataProvider-error/GigasecondTest.php
index 8b193d4..e0903b4 100644
--- a/tests/dataProvider-error/GigasecondTest.php
+++ b/tests/dataProvider-error/GigasecondTest.php
@@ -37,7 +37,7 @@ public function dateSetup($date): DateTimeImmutable
         return new DateTimeImmutable($date, $UTC);
     }
 
-    public function inputAndExpectedDates(): array
+    public static function inputAndExpectedDates(): array
     {
         return [
             ['2011-04-25', '2043-01-01 01:46:40'],
@@ -48,7 +48,7 @@ public function inputAndExpectedDates(): array
         ];
     }
 
-    public function inputDates(): array
+    public static function inputDates(): array
     {
         return [
             ['2011-04-25'],
diff --git a/tests/error-with-task-id/HelloWorld.php b/tests/error-with-task-id/HelloWorld.php
new file mode 100644
index 0000000..52c7826
--- /dev/null
+++ b/tests/error-with-task-id/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    throw new \BadFunctionCallException("Implement the helloWorld() function");
+}
diff --git a/tests/error-with-task-id/HelloWorldTest.php b/tests/error-with-task-id/HelloWorldTest.php
new file mode 100644
index 0000000..1a5275f
--- /dev/null
+++ b/tests/error-with-task-id/HelloWorldTest.php
@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    /** @task_id 99 */
+    public function testHelloWorld(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/error-with-task-id/expected_results.json b/tests/error-with-task-id/expected_results.json
new file mode 100644
index 0000000..e3f60e3
--- /dev/null
+++ b/tests/error-with-task-id/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"fail","tests":[{"name":"Hello world","status":"error","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","task_id":99,"message":"HelloWorldTest::testHelloWorld\nBadFunctionCallException: Implement the helloWorld() function\n\nHelloWorld.php:5\nHelloWorldTest.php:15"}]}
diff --git a/tests/fail-with-array/HelloWorld.php b/tests/fail-with-array/HelloWorld.php
new file mode 100644
index 0000000..9203e10
--- /dev/null
+++ b/tests/fail-with-array/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return ["Goodbye, Mars!"];
+}
diff --git a/tests/fail-with-array/HelloWorldTest.php b/tests/fail-with-array/HelloWorldTest.php
new file mode 100644
index 0000000..ce11e8c
--- /dev/null
+++ b/tests/fail-with-array/HelloWorldTest.php
@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    public function testHelloWorld(): void
+    {
+        $this->assertEquals(['Hello, World!'], helloWorld());
+    }
+}
diff --git a/tests/fail-with-array/expected_results.json b/tests/fail-with-array/expected_results.json
new file mode 100644
index 0000000..d285488
--- /dev/null
+++ b/tests/fail-with-array/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"fail","tests":[{"name":"Hello world","status":"fail","test_code":"$this->assertEquals(['Hello, World!'], helloWorld());\n","message":"HelloWorldTest::testHelloWorld\nFailed asserting that two arrays are equal.\n--- Expected\n+++ Actual\n@@ @@\n Array (\n-    0 => 'Hello, World!'\n+    0 => 'Goodbye, Mars!'\n )\n\nHelloWorldTest.php:14"}]}
diff --git a/tests/fail-with-task-id/HelloWorld.php b/tests/fail-with-task-id/HelloWorld.php
new file mode 100644
index 0000000..2e09437
--- /dev/null
+++ b/tests/fail-with-task-id/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return "Goodbye, Mars!";
+}
diff --git a/tests/fail-with-task-id/HelloWorldTest.php b/tests/fail-with-task-id/HelloWorldTest.php
new file mode 100644
index 0000000..1a5275f
--- /dev/null
+++ b/tests/fail-with-task-id/HelloWorldTest.php
@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    /** @task_id 99 */
+    public function testHelloWorld(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/fail-with-task-id/expected_results.json b/tests/fail-with-task-id/expected_results.json
new file mode 100644
index 0000000..d2069b1
--- /dev/null
+++ b/tests/fail-with-task-id/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"fail","tests":[{"name":"Hello world","status":"fail","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","task_id":99,"message":"HelloWorldTest::testHelloWorld\nFailed asserting that two strings are equal.\n--- Expected\n+++ Actual\n@@ @@\n-'Hello, World!'\n+'Goodbye, Mars!'\n\nHelloWorldTest.php:15"}]}
diff --git a/tests/success-with-testdox-and-task-id/HelloWorld.php b/tests/success-with-testdox-and-task-id/HelloWorld.php
new file mode 100644
index 0000000..a017bb7
--- /dev/null
+++ b/tests/success-with-testdox-and-task-id/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return "Hello, World!";
+}
diff --git a/tests/success-with-testdox-and-task-id/HelloWorldTest.php b/tests/success-with-testdox-and-task-id/HelloWorldTest.php
new file mode 100644
index 0000000..1331ba9
--- /dev/null
+++ b/tests/success-with-testdox-and-task-id/HelloWorldTest.php
@@ -0,0 +1,20 @@
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\Attributes\TestDox;
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    /** @task_id 99 */
+    #[TestDox('"Hello, World!" from TestDox attribute')]
+    public function testNameDoesNotMatter(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/success-with-testdox-and-task-id/expected_results.json b/tests/success-with-testdox-and-task-id/expected_results.json
new file mode 100644
index 0000000..d1cd18d
--- /dev/null
+++ b/tests/success-with-testdox-and-task-id/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"pass","tests":[{"name":"\"Hello, World!\" from TestDox attribute","status":"pass","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","task_id":99}]}
diff --git a/tests/success-with-testdox-and-uuid/HelloWorld.php b/tests/success-with-testdox-and-uuid/HelloWorld.php
new file mode 100644
index 0000000..a017bb7
--- /dev/null
+++ b/tests/success-with-testdox-and-uuid/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return "Hello, World!";
+}
diff --git a/tests/success-with-testdox-and-uuid/HelloWorldTest.php b/tests/success-with-testdox-and-uuid/HelloWorldTest.php
new file mode 100644
index 0000000..c05a099
--- /dev/null
+++ b/tests/success-with-testdox-and-uuid/HelloWorldTest.php
@@ -0,0 +1,20 @@
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\Attributes\TestDox;
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    /** uuid: af9ffe10-dc13-42d8-a742-e7bdafac449d */
+    #[TestDox('"Hello, World!" from TestDox attribute')]
+    public function testNameDoesNotMatter(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/success-with-testdox-and-uuid/expected_results.json b/tests/success-with-testdox-and-uuid/expected_results.json
new file mode 100644
index 0000000..ac94f9d
--- /dev/null
+++ b/tests/success-with-testdox-and-uuid/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"pass","tests":[{"name":"\"Hello, World!\" from TestDox attribute","status":"pass","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n"}]}
diff --git a/tests/success-with-testdox-uuid-and-task-id/HelloWorld.php b/tests/success-with-testdox-uuid-and-task-id/HelloWorld.php
new file mode 100644
index 0000000..a017bb7
--- /dev/null
+++ b/tests/success-with-testdox-uuid-and-task-id/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return "Hello, World!";
+}
diff --git a/tests/success-with-testdox-uuid-and-task-id/HelloWorldTest.php b/tests/success-with-testdox-uuid-and-task-id/HelloWorldTest.php
new file mode 100644
index 0000000..27557c9
--- /dev/null
+++ b/tests/success-with-testdox-uuid-and-task-id/HelloWorldTest.php
@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\Attributes\TestDox;
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    /**
+     * uuid: af9ffe10-dc13-42d8-a742-e7bdafac449d
+     * @task_id 99
+     */
+    #[TestDox('"Hello, World!" from TestDox attribute')]
+    public function testNameDoesNotMatter(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/success-with-testdox-uuid-and-task-id/expected_results.json b/tests/success-with-testdox-uuid-and-task-id/expected_results.json
new file mode 100644
index 0000000..d1cd18d
--- /dev/null
+++ b/tests/success-with-testdox-uuid-and-task-id/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"pass","tests":[{"name":"\"Hello, World!\" from TestDox attribute","status":"pass","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n","task_id":99}]}
diff --git a/tests/success-with-testdox/HelloWorld.php b/tests/success-with-testdox/HelloWorld.php
new file mode 100644
index 0000000..a017bb7
--- /dev/null
+++ b/tests/success-with-testdox/HelloWorld.php
@@ -0,0 +1,6 @@
+<?php
+
+function helloWorld()
+{
+    return "Hello, World!";
+}
diff --git a/tests/success-with-testdox/HelloWorldTest.php b/tests/success-with-testdox/HelloWorldTest.php
new file mode 100644
index 0000000..83bbafe
--- /dev/null
+++ b/tests/success-with-testdox/HelloWorldTest.php
@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\Attributes\TestDox;
+
+class HelloWorldTest extends PHPUnit\Framework\TestCase
+{
+    public static function setUpBeforeClass(): void
+    {
+        require_once 'HelloWorld.php';
+    }
+
+    #[TestDox('"Hello, World!" from TestDox attribute')]
+    public function testNameDoesNotMatter(): void
+    {
+        $this->assertEquals('Hello, World!', helloWorld());
+    }
+}
diff --git a/tests/success-with-testdox/expected_results.json b/tests/success-with-testdox/expected_results.json
new file mode 100644
index 0000000..ac94f9d
--- /dev/null
+++ b/tests/success-with-testdox/expected_results.json
@@ -0,0 +1 @@
+{"version":3,"status":"pass","tests":[{"name":"\"Hello, World!\" from TestDox attribute","status":"pass","test_code":"$this->assertEquals('Hello, World!', helloWorld());\n"}]}