diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2e3b3c9..55b2a68 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,8 +13,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php: ['7.4']
-        dependencies: [highest, lowest]
+        php: ['7.4', '8.0', '8.1', '8.2', '8.3', '8.4', '8.5']
+        dependencies: [highest]
+        include:
+          - php: '7.4'
+            dependencies: lowest
 
     steps:
       - uses: actions/checkout@v6
@@ -25,6 +28,9 @@ jobs:
           php-version: ${{ matrix.php }}
           tools: composer:v2
 
+      - name: Align composer platform.php with matrix PHP version
+        run: composer config platform.php ${{ matrix.php }}
+
       - name: Install dependencies
         uses: ramsey/composer-install@v4
         with:
diff --git a/composer.json b/composer.json
index edf8ab6..e2349e7 100644
--- a/composer.json
+++ b/composer.json
@@ -26,7 +26,7 @@
         }
     ],
     "require": {
-        "php": "^7.4",
+        "php": "^7.4 || ^8.0",
         "symfony/console": "^3.4 | ^4.0 | ^5.0"
     },
     "require-dev": {
diff --git a/composer.lock b/composer.lock
index 1f1065c..2da5391 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "ad3c92c419ec035c3134e447270994bb",
+    "content-hash": "45bd62a296a29299ed7ec69b6e2332f7",
     "packages": [
         {
             "name": "psr/container",
@@ -2951,7 +2951,7 @@
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {
-        "php": "^7.4"
+        "php": "^7.4 || ^8.0"
     },
     "platform-dev": {},
     "platform-overrides": {
diff --git a/src/Diff/ConsoleDiff.php b/src/Diff/ConsoleDiff.php
index b9e5693..0197c5b 100644
--- a/src/Diff/ConsoleDiff.php
+++ b/src/Diff/ConsoleDiff.php
@@ -28,7 +28,7 @@ class ConsoleDiff extends FirstDiff
      *
      * @param CursorInterface|null $cursor The cursor used to move around the screen
      */
-    public function __construct(CursorInterface $cursor = null)
+    public function __construct(?CursorInterface $cursor = null)
     {
         $this->cursor = $cursor ?: new ANSI();
     }
diff --git a/src/DiffConsoleOutput.php b/src/DiffConsoleOutput.php
index 7fb3e91..97cb9fd 100644
--- a/src/DiffConsoleOutput.php
+++ b/src/DiffConsoleOutput.php
@@ -49,8 +49,8 @@ class DiffConsoleOutput implements OutputInterface
      */
     public function __construct(
         OutputInterface $output,
-        TerminalInterface $terminal = null,
-        Wrapper $wrapper = null
+        ?TerminalInterface $terminal = null,
+        ?Wrapper $wrapper = null
     ) {
         $this->output = $output;
         $this->terminal = $terminal ?: new Terminal();
diff --git a/src/Terminal/Terminal.php b/src/Terminal/Terminal.php
index b57d59b..a3293d1 100644
--- a/src/Terminal/Terminal.php
+++ b/src/Terminal/Terminal.php
@@ -26,7 +26,7 @@ class Terminal implements TerminalInterface
      * @param CursorInterface|null $cursor
      * @param DimensionsInterface  $dimensions
      */
-    public function __construct(CursorInterface $cursor = null, DimensionsInterface $dimensions = null)
+    public function __construct(?CursorInterface $cursor = null, ?DimensionsInterface $dimensions = null)
     {
         $this->cursor = $cursor ?: new ANSI();
         $this->dimensions = $dimensions ?: new TerminalDimensions();