diff --git a/.gitignore b/.gitignore
index 7579f74..50b321e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 vendor
 composer.lock
+.phpunit.result.cache
diff --git a/Dockerfile b/Dockerfile
index 5c4464d..56e97a7 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -24,4 +24,9 @@ RUN curl -O https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli
     chmod +x wp-cli.phar && \
     mv wp-cli.phar /usr/local/bin/wp
 
+COPY composer.json composer.lock /app/
+RUN composer install --no-scripts --no-autoloader
+RUN composer global require yoast/phpunit-polyfills:"^3.0" --dev
+ENV PATH="/root/.composer/vendor/bin:${PATH}"
+
 RUN chmod +x -R ./
diff --git a/composer.json b/composer.json
index 58c647d..df3df13 100644
--- a/composer.json
+++ b/composer.json
@@ -3,8 +3,8 @@
     "description": "The ActivityPub Event Extensions help for event custom post types to federate properly.",
     "type": "wordpress-plugin",
     "require": {
-        "php": ">=5.6.0",
-        "composer/installers": "^1.0 || ^2.0"
+        "php": ">=8.1.0",
+        "composer/installers": "^2.0"
     },
     "require-dev": {
         "phpcompatibility/php-compatibility": "*",
@@ -39,8 +39,8 @@
         ],
         "test": [
             "composer install",
-            "tests/install-wp-tests.sh activitypub-test root activitypub-test test-db latest true",
-            "vendor/bin/phpunit"
+            "tests/install-wp-tests.sh wordpress-test root wordpress-test test-db latest true",
+            "phpunit"
         ]
     }
 }
diff --git a/docker-compose-test.yml b/docker-compose.yml
similarity index 52%
rename from docker-compose-test.yml
rename to docker-compose.yml
index 3926e0e..4891aa8 100644
--- a/docker-compose-test.yml
+++ b/docker-compose.yml
@@ -1,16 +1,19 @@
 version: '3'
+
+# This files purpose is to run the PHPunit tests locally.
+
 services:
   test-db:
-    platform: linux/x86_64
     image: mariadb
     environment:
-      MYSQL_DATABASE: wordpress
-      MYSQL_ROOT_PASSWORD: wordpress
+      MARIADB_DATABASE: wordpress-test
+      MARIADB_ROOT_PASSWORD: wordpress-test
     healthcheck:
-        test: ["CMD", "curl", "-f", "http://localhost:3306"]
-        interval: 5s
-        timeout: 2s
-        retries: 5
+      test: ["CMD", "healthcheck.sh", "--connect", "--innodb_initialized"]
+      start_period: 5s
+      interval: 4s
+      timeout: 5s
+      retries: 5
 
   test-php:
     build:
diff --git a/tests/install-wp-tests.sh b/tests/install-wp-tests.sh
old mode 100644
new mode 100755
index f10e7c3..286ea40
--- a/tests/install-wp-tests.sh
+++ b/tests/install-wp-tests.sh
@@ -194,8 +194,11 @@ install_wp_plugins() {
         echo "Skipping WordPress plugin installation."
         return 0
     fi
-    download https://downloads.wordpress.org/plugin/activitypub.3.2.5.zip $TMPDIR/activitypub.zip
-	unzip $TMPDIR/activitypub.zip -d $WP_CORE_DIR/wp-content/plugins/
+	ACTIVITYPUB_FILE="activitypub.3.2.5.zip"
+	if ! test -f $TMPDIR/$ACTIVITYPUB_FILE; then
+	    download https://downloads.wordpress.org/plugin/$ACTIVITYPUB_FILE $TMPDIR/$ACTIVITYPUB_FILE
+	fi
+	unzip -o $TMPDIR/$ACTIVITYPUB_FILE -d $WP_CORE_DIR/wp-content/plugins/
 }
 
 install_wp