diff --git a/acp/viglink_helper.php b/acp/viglink_helper.php
index 36bf313..5ec8af6 100644
--- a/acp/viglink_helper.php
+++ b/acp/viglink_helper.php
@@ -66,7 +66,7 @@ public function __construct(\phpbb\cache\driver\driver_interface $cache, \phpbb\
 	 *
 	 * @return void
 	 */
-	public function set_viglink_services($force_update = false, $force_cache = false)
+	public function set_viglink_services($force_update = false, $force_cache = false): void
 	{
 		$cache_key = '_versioncheck_viglink_' . $this->use_ssl;
 
@@ -114,7 +114,7 @@ public function set_viglink_services($force_update = false, $force_cache = false
 	 *
 	 * @return void
 	 */
-	protected function set_viglink_configs($data)
+	protected function set_viglink_configs($data): void
 	{
 		$viglink_configs = array(
 			'allow_viglink_phpbb',
@@ -137,7 +137,7 @@ protected function set_viglink_configs($data)
 	 *
 	 * @param string $message The error message
 	 */
-	public function log_viglink_error($message)
+	public function log_viglink_error($message): void
 	{
 		$user_id = empty($this->user->data) ? ANONYMOUS : $this->user->data['user_id'];
 		$user_ip = empty($this->user->ip) ? '' : $this->user->ip;
diff --git a/acp/viglink_info.php b/acp/viglink_info.php
index a2c891a..883721a 100644
--- a/acp/viglink_info.php
+++ b/acp/viglink_info.php
@@ -15,7 +15,7 @@
  */
 class viglink_info
 {
-	public function module()
+	public function module(): array
 	{
 		return array(
 			'filename'	=> '\phpbb\viglink\acp\viglink_module',
diff --git a/acp/viglink_module.php b/acp/viglink_module.php
index 1927d7b..4fc152d 100644
--- a/acp/viglink_module.php
+++ b/acp/viglink_module.php
@@ -31,7 +31,7 @@ class viglink_module
 	 *
 	 * @throws \Exception
 	 */
-	public function main($id, $mode)
+	public function main($id, $mode): void
 	{
 		global $phpbb_container;
 
diff --git a/cron/viglink.php b/cron/viglink.php
index f01bcf6..c9e2f9f 100644
--- a/cron/viglink.php
+++ b/cron/viglink.php
@@ -37,7 +37,7 @@ public function __construct(\phpbb\config\config $config, \phpbb\viglink\acp\vig
 	/**
 	 * {@inheritDoc}
 	 */
-	public function run()
+	public function run(): void
 	{
 		try
 		{
@@ -52,7 +52,7 @@ public function run()
 	/**
 	 * {@inheritDoc}
 	 */
-	public function is_runnable()
+	public function is_runnable(): bool
 	{
 		return (bool) $this->config['viglink_enabled'];
 	}
@@ -60,7 +60,7 @@ public function is_runnable()
 	/**
 	 * {@inheritDoc}
 	 */
-	public function should_run()
+	public function should_run(): bool
 	{
 		return $this->config['viglink_last_gc'] < strtotime('24 hours ago');
 	}
diff --git a/event/acp_listener.php b/event/acp_listener.php
index 9e1606c..65269ee 100644
--- a/event/acp_listener.php
+++ b/event/acp_listener.php
@@ -70,7 +70,7 @@ public function __construct(\phpbb\config\config $config, \phpbb\language\langua
 	/**
 	 * {@inheritDoc}
 	 */
-	public static function getSubscribedEvents()
+	public static function getSubscribedEvents(): array
 	{
 		return array(
 			'core.acp_main_notice'				=> 'set_viglink_services',
@@ -85,7 +85,7 @@ public static function getSubscribedEvents()
 	 *
 	 * @return void
 	 */
-	public function set_viglink_services()
+	public function set_viglink_services(): void
 	{
 		try
 		{
@@ -111,7 +111,7 @@ public function set_viglink_services()
 	 *
 	 * @return void
 	 */
-	public function update_viglink_settings($event)
+	public function update_viglink_settings($event): void
 	{
 		$this->language->add_lang('viglink_module_acp', 'phpbb/viglink');
 
diff --git a/event/listener.php b/event/listener.php
index 63e0855..22a60f5 100644
--- a/event/listener.php
+++ b/event/listener.php
@@ -38,7 +38,7 @@ public function __construct(\phpbb\config\config $config, \phpbb\template\templa
 	/**
 	 * {@inheritDoc}
 	 */
-	public static function getSubscribedEvents()
+	public static function getSubscribedEvents(): array
 	{
 		return array(
 			'core.viewtopic_post_row_after'		=> 'display_viglink',
@@ -50,7 +50,7 @@ public static function getSubscribedEvents()
 	 *
 	 * @return void
 	 */
-	public function display_viglink()
+	public function display_viglink(): void
 	{
 		$viglink_key = '';
 
diff --git a/ext.php b/ext.php
index c05d421..e91a3c5 100644
--- a/ext.php
+++ b/ext.php
@@ -24,7 +24,7 @@ class ext extends \phpbb\extension\base
 	 *
 	 * @return bool
 	 */
-	public function is_enableable()
+	public function is_enableable(): bool
 	{
 		return phpbb_version_compare(PHPBB_VERSION, '3.2.0-b1', '>=');
 	}
diff --git a/migrations/viglink_ask_admin.php b/migrations/viglink_ask_admin.php
index b216964..6d81f43 100644
--- a/migrations/viglink_ask_admin.php
+++ b/migrations/viglink_ask_admin.php
@@ -15,17 +15,17 @@
  */
 class viglink_ask_admin extends \phpbb\db\migration\migration
 {
-	public static function depends_on()
+	public static function depends_on(): array
 	{
 		return array('\phpbb\viglink\migrations\viglink_data_v2');
 	}
 
-	public function effectively_installed()
+	public function effectively_installed(): bool
 	{
 		return isset($this->config['viglink_ask_admin']);
 	}
 
-	public function update_data()
+	public function update_data(): array
 	{
 		return array(
 			array('if', array(
diff --git a/migrations/viglink_ask_admin_wait.php b/migrations/viglink_ask_admin_wait.php
index d6f1fb2..9c5c771 100644
--- a/migrations/viglink_ask_admin_wait.php
+++ b/migrations/viglink_ask_admin_wait.php
@@ -15,17 +15,17 @@
  */
 class viglink_ask_admin_wait extends \phpbb\db\migration\migration
 {
-	public static function depends_on()
+	public static function depends_on(): array
 	{
 		return array('\phpbb\viglink\migrations\viglink_ask_admin');
 	}
 
-	public function effectively_installed()
+	public function effectively_installed(): bool
 	{
 		return isset($this->config['viglink_ask_admin_last']);
 	}
 
-	public function update_data()
+	public function update_data(): array
 	{
 		return array(
 			array('if', array(
diff --git a/migrations/viglink_cron.php b/migrations/viglink_cron.php
index fd0f8f0..52c5654 100644
--- a/migrations/viglink_cron.php
+++ b/migrations/viglink_cron.php
@@ -15,17 +15,17 @@
  */
 class viglink_cron extends \phpbb\db\migration\migration
 {
-	public static function depends_on()
+	public static function depends_on(): array
 	{
 		return array('\phpbb\viglink\migrations\viglink_data');
 	}
 
-	public function effectively_installed()
+	public function effectively_installed(): bool
 	{
 		return isset($this->config['viglink_last_gc']);
 	}
 
-	public function update_data()
+	public function update_data(): array
 	{
 		return array(
 			array('config.add', array('viglink_last_gc', 0, true)),
diff --git a/migrations/viglink_data.php b/migrations/viglink_data.php
index e5c208e..c1b3bba 100644
--- a/migrations/viglink_data.php
+++ b/migrations/viglink_data.php
@@ -15,17 +15,17 @@
  */
 class viglink_data extends \phpbb\db\migration\migration
 {
-	public static function depends_on()
+	public static function depends_on(): array
 	{
 		return array('\phpbb\db\migration\data\v31x\v312');
 	}
 
-	public function effectively_installed()
+	public function effectively_installed(): bool
 	{
 		return isset($this->config['phpbb_viglink_api_key']);
 	}
 
-	public function update_data()
+	public function update_data(): array
 	{
 		return array(
 			// Basic config options
diff --git a/migrations/viglink_data_v2.php b/migrations/viglink_data_v2.php
index 93f2fcf..c905874 100644
--- a/migrations/viglink_data_v2.php
+++ b/migrations/viglink_data_v2.php
@@ -15,17 +15,17 @@
  */
 class viglink_data_v2 extends \phpbb\db\migration\migration
 {
-	public static function depends_on()
+	public static function depends_on(): array
 	{
 		return array('\phpbb\viglink\migrations\viglink_data');
 	}
 
-	public function effectively_installed()
+	public function effectively_installed(): bool
 	{
 		return !isset($this->config['viglink_api_key']);
 	}
 
-	public function update_data()
+	public function update_data(): array
 	{
 		return array(
 			array('config.remove', array('viglink_api_key')),