diff --git a/phpstan.neon b/phpstan.neon
index 5891e2f..839b2cd 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -23,6 +23,8 @@ parameters:
 
         - '#Call to an undefined method DateTimeInterface::#'
 
+        - '#PHPDoc tag @var for property ipl\\Scheduler\\Scheduler::.* contains unresolvable type#'
+
         - '#Call to an undefined method React\\Promise\\PromiseInterface::#'
 
         - '#Method ipl\\Scheduler\\.* should return \$this.* but returns static#'
diff --git a/src/Common/Promises.php b/src/Common/Promises.php
index b896627..33cede1 100644
--- a/src/Common/Promises.php
+++ b/src/Common/Promises.php
@@ -4,13 +4,13 @@
 
 use ArrayObject;
 use InvalidArgumentException;
+use ipl\Scheduler\ObjectStorage;
 use Ramsey\Uuid\UuidInterface;
 use React\Promise\PromiseInterface;
-use SplObjectStorage;
 
 trait Promises
 {
-    /** @var SplObjectStorage<UuidInterface, ArrayObject<int, PromiseInterface>> */
+    /** @var ObjectStorage<UuidInterface, ArrayObject<int, PromiseInterface>> */
     protected $promises;
 
     /**
diff --git a/src/Common/Timers.php b/src/Common/Timers.php
index 2d0641f..719202a 100644
--- a/src/Common/Timers.php
+++ b/src/Common/Timers.php
@@ -2,13 +2,13 @@
 
 namespace ipl\Scheduler\Common;
 
+use ipl\Scheduler\ObjectStorage;
 use Ramsey\Uuid\UuidInterface;
 use React\EventLoop\TimerInterface;
-use SplObjectStorage;
 
 trait Timers
 {
-    /** @var SplObjectStorage<UuidInterface, TimerInterface> */
+    /** @var ObjectStorage<UuidInterface, TimerInterface> */
     protected $timers;
 
     /**
diff --git a/src/ObjectStorage.php b/src/ObjectStorage.php
new file mode 100644
index 0000000..9553afb
--- /dev/null
+++ b/src/ObjectStorage.php
@@ -0,0 +1,29 @@
+<?php
+
+namespace ipl\Scheduler;
+
+use ipl\Scheduler\Contract\Task;
+use Ramsey\Uuid\UuidInterface;
+use SplObjectStorage;
+
+/**
+ * ObjectStorage provides custom implementation of the internal PHP hash method and doesn't depend on the
+ * `spl_object_hash()` function used by `SplObjectStorage` class.
+ *
+ * @extends SplObjectStorage<object, object|mixed>
+ */
+class ObjectStorage extends SplObjectStorage
+{
+    public function getHash($object): string
+    {
+        if ($object instanceof Task) {
+            return $object->getUuid()->toString();
+        }
+
+        if ($object instanceof UuidInterface) {
+            return $object->toString();
+        }
+
+        return parent::getHash($object);
+    }
+}
diff --git a/src/Scheduler.php b/src/Scheduler.php
index 25ad3a1..0d6618b 100644
--- a/src/Scheduler.php
+++ b/src/Scheduler.php
@@ -12,7 +12,6 @@
 use React\EventLoop\Loop;
 use React\Promise;
 use React\Promise\ExtendedPromiseInterface;
-use SplObjectStorage;
 use Throwable;
 
 class Scheduler
@@ -124,15 +123,15 @@ class Scheduler
      */
     public const ON_TASK_EXPIRED = 'task-expired';
 
-    /** @var SplObjectStorage<Task, null> The scheduled tasks of this scheduler */
+    /** @var ObjectStorage<Task, null> The scheduled tasks of this scheduler */
     protected $tasks;
 
     public function __construct()
     {
-        $this->tasks = new SplObjectStorage();
+        $this->tasks = new ObjectStorage();
 
-        $this->promises = new SplObjectStorage();
-        $this->timers = new SplObjectStorage();
+        $this->promises = new ObjectStorage();
+        $this->timers = new ObjectStorage();
 
         $this->init();
     }
@@ -177,7 +176,7 @@ public function removeTasks(): self
             $this->cancelTask($task);
         }
 
-        $this->tasks = new SplObjectStorage();
+        $this->tasks = new ObjectStorage();
 
         return $this;
     }