diff --git a/README.md b/README.md
index a5e9182..97b979f 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ This library allows you to quickly and easily use the Buffer Web API v1 via PHP.
 ## Getting Started
 
 ### Prerequisites
-- PHP >=7.2
+- PHP >=8.2
 
 ### Installation
 Run into the terminal the next command
diff --git a/composer.json b/composer.json
index 801e35c..b641534 100644
--- a/composer.json
+++ b/composer.json
@@ -8,17 +8,18 @@
     "Bufferapp"
   ],
   "require": {
-    "php": ">=7.2",
+    "php": ">=8.2",
     "ext-curl": "*",
     "ext-json": "*",
     "ext-mbstring": "*",
     "ext-openssl": "*",
-    "symfony/http-client": "^4.3"
+    "symfony/http-client": "^7.2"
   },
   "require-dev": {
     "squizlabs/php_codesniffer": "3.*",
     "swaggest/json-diff": "^3.4",
-    "phpunit/phpunit": "^8.3"
+    "phpunit/phpunit": "^8.3",
+    "phpstan/phpstan": "^2.0"
   },
   "type": "library",
   "autoload": {
diff --git a/lib/Auth/AuthorizationToken.php b/lib/Auth/AuthorizationToken.php
index 35636c3..f4576b7 100644
--- a/lib/Auth/AuthorizationToken.php
+++ b/lib/Auth/AuthorizationToken.php
@@ -19,8 +19,6 @@ public function __construct(string $accessToken)
 
     /**
      * Get Access Token.
-     *
-     * @return string
      */
     public function getAccessToken(): string
     {
diff --git a/lib/Auth/AuthorizationTokenInterface.php b/lib/Auth/AuthorizationTokenInterface.php
index 96b5435..f205135 100644
--- a/lib/Auth/AuthorizationTokenInterface.php
+++ b/lib/Auth/AuthorizationTokenInterface.php
@@ -4,5 +4,5 @@
 
 interface AuthorizationTokenInterface
 {
-    public function getAccessToken();
+    public function getAccessToken() : string;
 }
diff --git a/lib/Http/Client.php b/lib/Http/Client.php
index 08c0371..bfaa623 100644
--- a/lib/Http/Client.php
+++ b/lib/Http/Client.php
@@ -24,20 +24,16 @@ class Client implements ClientInterface
      */
     public function __construct(AuthorizationTokenInterface $auth)
     {
-        $this->httpClient = HttpClient::create(['headers' => [
-            'Authorization' => 'Bearer '.$auth->getAccessToken(),
-        ]]);
+        $this->httpClient = HttpClient::create([
+            'headers' => [
+                'Authorization' => 'Bearer ' . $auth->getAccessToken(),
+            ]
+        ]);
     }
 
     /**
      * Create Http Request and send the request.
      *
-     * @param string $method
-     * @param string $url
-     * @param array $options
-     *
-     * @return array
-     *
      * @throws TransportExceptionInterface
      * @throws DecodingExceptionInterface    When the body cannot be decoded to an array
      * @throws TransportExceptionInterface   When a network error occurs
@@ -47,9 +43,7 @@ public function __construct(AuthorizationTokenInterface $auth)
      */
     public function createHttpRequest(string $method, string $endpoint, array $options = []): array
     {
-        $response = $this->httpClient->request($method, $this->baseURL.$endpoint, $options);
-        $responseArray = $response->toArray();
-
-        return $responseArray;
+        $response = $this->httpClient->request($method, $this->baseURL . $endpoint, $options);
+        return $response->toArray();
     }
 }
diff --git a/lib/Model/Schedule.php b/lib/Model/Schedule.php
index e120bab..b0aaa8c 100644
--- a/lib/Model/Schedule.php
+++ b/lib/Model/Schedule.php
@@ -19,29 +19,29 @@ class Schedule
      *
      * @var array
      */
-    protected $days = array();
+    protected $days = [];
 
     /**
      * Array of scheduled times.
      *
      * @var array
      */
-    protected $times = array();
+    protected $times = [];
 
     /**
      * Create a new Schedule instance.
      *
-     * @param  array  $days
-     * @param  array  $times
+     * @param array $days
+     * @param array $times
      * @return void
      */
-    public function __construct($days = array(), $times = array())
+    public function __construct($days = [], $times = [])
     {
-        if (! empty($days)) {
+        if (!empty($days)) {
             $this->addDay($days);
         }
 
-        if (! empty($times)) {
+        if (!empty($times)) {
             $this->addTime($times);
         }
     }
@@ -49,17 +49,17 @@ public function __construct($days = array(), $times = array())
     /**
      * Schedule a new day.
      *
-     * @param  string|array  $day
+     * @param string|array $day
      * @return Schedule
      */
     public function addDay($day): self
     {
-        $available = array('mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun');
+        $available = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun'];
 
-        foreach ((array) $day as $value) {
+        foreach ((array)$day as $value) {
             // only accept valid values
-            if (! in_array($value, $available)) {
-                throw new InvalidArgumentException('Day must be a valid value: '.implode(', ', $available));
+            if (!in_array($value, $available)) {
+                throw new InvalidArgumentException('Day must be a valid value: ' . implode(', ', $available));
             }
 
             $this->days[] = $value;
@@ -76,9 +76,9 @@ public function addDay($day): self
      */
     public function addTime($time): self
     {
-        foreach ((array) $time as $value) {
+        foreach ((array)$time as $value) {
             // only accept valid times (HH:mm)
-            if (! preg_match('#([01][0-9]|2[0-3]):[0-5][0-9]#', $value)) {
+            if (!preg_match('#([01][0-9]|2[0-3]):[0-5][0-9]#', $value)) {
                 throw new InvalidArgumentException('Time must be valid: HH:mm.');
             }
 
diff --git a/lib/Model/Update.php b/lib/Model/Update.php
index 2aab8df..57a85c0 100644
--- a/lib/Model/Update.php
+++ b/lib/Model/Update.php
@@ -18,7 +18,7 @@ class Update
     /**
      * The status update text.
      *
-     * @var string
+     * @var string|null
      */
     public $text = null;
 
@@ -28,7 +28,7 @@ class Update
      *
      * @var array
      */
-    public $profiles = array();
+    public $profiles = [];
 
     /**
      * If shorten is false links within the text will not be automatically
@@ -60,14 +60,14 @@ class Update
      *
      * @var array
      */
-    public $media = array();
+    public $media = [];
 
     /**
      * A date describing when the update should be posted. Overrides any top or
      * now parameter. When using ISO 8601 format, if no UTC offset is specified,
      * UTC is assumed.
      *
-     * @var \DateTime
+     * @var string|null
      */
     public $scheduled_at = null;
 
@@ -93,11 +93,11 @@ public function addProfile($id): self
      */
     public function addMedia($key, $value): self
     {
-        $available = array('link', 'description', 'picture', 'photo');
+        $available = ['link', 'description', 'picture', 'photo'];
 
         // accept only valid types for media
         if (!in_array($key, $available)) {
-            throw new InvalidArgumentException('Media type must be a valid value: '.implode(', ', $available).'.');
+            throw new InvalidArgumentException('Media type must be a valid value: ' . implode(', ', $available) . '.');
         }
 
         $this->media[$key] = $value;
@@ -125,7 +125,7 @@ public function schedule($when): self
         return $this;
     }
 
-    public function validate()
+    public function validate(): void
     {
         if ((!isset($this->text) || trim($this->text) === '')) {
             throw new InvalidArgumentException('text field should be filled');
diff --git a/lib/Service/ProfileService.php b/lib/Service/ProfileService.php
index f0226b8..3d5c5ad 100644
--- a/lib/Service/ProfileService.php
+++ b/lib/Service/ProfileService.php
@@ -39,7 +39,7 @@ public function getProfiles(): array
      */
     public function getProfile(string $profileID): array
     {
-        return $this->client->createHttpRequest('GET', 'profiles/'.$profileID.'.json');
+        return $this->client->createHttpRequest('GET', "profiles/{$profileID}.json");
     }
 
     /**
@@ -51,7 +51,7 @@ public function getProfile(string $profileID): array
      */
     public function getSchedules(string $profileID): array
     {
-        return $this->client->createHttpRequest('GET', 'profiles/'.$profileID.'/schedules.json');
+        return $this->client->createHttpRequest('GET', "profiles/{$profileID}/schedules.json");
     }
 
     /**
@@ -64,15 +64,15 @@ public function getSchedules(string $profileID): array
      */
     public function updateSchedule(string $profileID, Schedule $schedule): array
     {
-        $payload = array('schedules' => array());
-        $payload['schedules'][] = array(
-            'days'  => $schedule->getDays(),
+        $payload = ['schedules' => []];
+        $payload['schedules'][] = [
+            'days' => $schedule->getDays(),
             'times' => $schedule->getTimes(),
-        );
+        ];
 
         return $this->client->createHttpRequest(
             'POST',
-            'profiles/'.$profileID.'/schedules/update.json',
+            "profiles/{$profileID}/schedules/update.json",
             [
                 'body' => $payload,
             ]
diff --git a/lib/Service/UpdateService.php b/lib/Service/UpdateService.php
index aa11034..824ef57 100644
--- a/lib/Service/UpdateService.php
+++ b/lib/Service/UpdateService.php
@@ -29,43 +29,29 @@ public function __construct(ClientInterface $client)
      */
     public function getUpdates(string $profileID): array
     {
-        return $this->client->createHttpRequest('GET', 'updates/'.$profileID.'.json');
+        return $this->client->createHttpRequest('GET', "updates/{$profileID}.json");
     }
 
     /**
      * Returns an array of updates that are currently in the buffer for an
      * individual social media profile.
      *
-     * @param string $profileID
-     *
-     * @param int $page
-     * @param int $count
-     * @param string|null $since
-     * @param bool $utc
-     *
      * @return array
      */
     public function getPendingUpdates(string $profileID, int $page = 1, int $count = 100, string $since = "", bool $utc = false): array
     {
-        return $this->client->createHttpRequest('GET', 'profiles/'.$profileID.'/updates/pending.json?page='.$page.'&count='.$count.'&since='.$since.'&utc='.$utc);
+        return $this->client->createHttpRequest('GET', "profiles/{$profileID}/updates/pending.json?page={$page}&count={$count}&since={$since}&utc={$utc}");
     }
 
     /**
      * Returns an array of updates that have been sent from the buffer for an
      * individual social media profile.
      *
-     * @param string $profileID
-     *
-     * @param int $page
-     * @param int $count
-     * @param string|null $since
-     * @param bool $utc
-     *
      * @return array
      */
     public function getSentUpdates(string $profileID, int $page = 1, int $count = 100, string $since = "", bool $utc = false, string $filter = ""): array
     {
-        return $this->client->createHttpRequest('GET', 'profiles/'.$profileID.'/updates/sent.json?page='.$page.'&count='.$count.'&since='.$since.'&utc='.$utc.'&filter='.$filter);
+        return $this->client->createHttpRequest('GET', "profiles/{$profileID}/updates/sent.json?page={$page}&count={$count}&since={$since}&utc={$utc}&filter={$filter}");
     }
 
     /**
@@ -77,11 +63,11 @@ public function getSentUpdates(string $profileID, int $page = 1, int $count = 10
      *
      * @return array
      */
-    public function reorderUpdates(string $profileID, array $order, int $offset = null, bool $utc = false): array
+    public function reorderUpdates(string $profileID, array $order, ?int $offset = null, bool $utc = false): array
     {
         return $this->client->createHttpRequest(
             'POST',
-            'profiles/'.$profileID.'/updates/reorder.json',
+            "profiles/{$profileID}/updates/reorder.json",
             [
                 'body' => [
                     'order' => $order,
@@ -102,11 +88,11 @@ public function reorderUpdates(string $profileID, array $order, int $offset = nu
      *
      * @return array
      */
-    public function shuffleUpdates(string $profileID, int $count = null, bool $utc = false): array
+    public function shuffleUpdates(string $profileID, ?int $count = null, bool $utc = false): array
     {
         return $this->client->createHttpRequest(
             'POST',
-            'profiles/'.$profileID.'/updates/shuffle.json',
+            "profiles/{$profileID}/updates/shuffle.json",
             [
                 'body' => [
                     'count' => $count,
@@ -125,13 +111,13 @@ public function createUpdate(Update $update): array
     {
         $update->validate();
 
-        $payload = array(
+        $payload = [
             'text' => $update->text,
             'profile_ids' => $update->profiles,
             'shorten' => $update->shorten,
             'now' => $update->now,
             'top' => $update->top,
-        );
+        ];
 
         if (!empty($update->media)) {
             $payload['media'] = $update->media;
@@ -158,10 +144,10 @@ public function updateUpdate(Update $update): array
     {
         $update->validate();
 
-        $payload = array(
+        $payload = [
             'text' => $update->text,
             'now' => $update->now,
-        );
+        ];
 
         if (!empty($update->media)) {
             $payload['media'] = $update->media;
@@ -172,7 +158,7 @@ public function updateUpdate(Update $update): array
 
         return $this->client->createHttpRequest(
             'POST',
-            'updates/'.$update->id.'/update.json',
+            "updates/{$update->id}/update.json",
             [
                 'body' => $payload,
             ]
@@ -189,7 +175,7 @@ public function shareUpdate(string $updateID): array
     {
         return $this->client->createHttpRequest(
             'POST',
-            'updates/'.$updateID.'/share.json'
+            "updates/{$updateID}/share.json"
         );
     }
 
@@ -202,7 +188,7 @@ public function deleteUpdate(string $updateID): array
     {
         return $this->client->createHttpRequest(
             'POST',
-            'updates/'.$updateID.'/destroy.json'
+            "updates/{$updateID}/destroy.json"
         );
     }
 
@@ -218,7 +204,7 @@ public function moveToTopUpdate(string $updateID): array
     {
         return $this->client->createHttpRequest(
             'POST',
-            'updates/'.$updateID.'/move_to_top.json'
+            "updates/{$updateID}/move_to_top.json"
         );
     }
 
@@ -231,6 +217,6 @@ public function moveToTopUpdate(string $updateID): array
      */
     public function getSharesLink(string $url): array
     {
-        return $this->client->createHttpRequest('GET', 'links/shares.json?url='.$url);
+        return $this->client->createHttpRequest('GET', "links/shares.json?url={$url}");
     }
 }
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..183067d
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,11 @@
+parameters:
+  level: 6
+  paths:
+      - ./
+  excludePaths:
+      - vendor/*
+      - tests/*
+  ignoreErrors:
+      -
+            identifier: missingType.iterableValue
+