diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
index 8cecea8..64db5f7 100644
--- a/.php-cs-fixer.dist.php
+++ b/.php-cs-fixer.dist.php
@@ -29,7 +29,6 @@
         'increment_style' => ['style' => 'pre'],
         'single_quote' => true,
         'trim_array_spaces' => true,
-        'single_blank_line_before_namespace' => true,
         'yoda_style' => false,
         'global_namespace_import' => [
             'import_classes' => false,
diff --git a/composer.json b/composer.json
index cb37fbc..5b18fbb 100644
--- a/composer.json
+++ b/composer.json
@@ -21,7 +21,7 @@
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3.2",
-        "phpstan/phpstan": "^0.12.69",
+        "phpstan/phpstan": "^1.10",
         "phpunit/phpunit": "^9.5"
     },
     "autoload": {
diff --git a/src/Await.php b/src/Await.php
index 71443f1..8abac46 100644
--- a/src/Await.php
+++ b/src/Await.php
@@ -48,4 +48,27 @@ public function until(callable $condition): void
             }
         }
     }
+
+    /**
+     * @template T
+     *
+     * @param callable(): T $closure
+     *
+     * @return T
+     */
+    public function on(callable $closure)
+    {
+        $start = microtime(true);
+        while (true) {
+            usleep($this->pollInterval);
+            try {
+                return $closure();
+            } catch (\Throwable $throwable) {
+            }
+
+            if (Duration::seconds(microtime(true) - $start) > $this->waitTime) {
+                throw new TimeoutException('Closure was not able to return value in the specified wait time');
+            }
+        }
+    }
 }
diff --git a/tests/AwaitTest.php b/tests/AwaitTest.php
index 67fed5d..f9c45b0 100644
--- a/tests/AwaitTest.php
+++ b/tests/AwaitTest.php
@@ -5,6 +5,7 @@
 namespace Akondas\Exspecto\Tests;
 
 use function Akondas\Exspecto\await;
+
 use Akondas\Exspecto\Duration;
 use Akondas\Exspecto\Exception\TimeoutException;
 use PHPUnit\Framework\TestCase;
@@ -37,4 +38,33 @@ public function testAwaitTimeout(): void
             return false;
         });
     }
+
+    public function testReturnValue(): void
+    {
+        $iterations = 5;
+        $start = microtime(true);
+
+        $value = await()->atMost(1)->pollInterval(10)->on(function () use (&$iterations): string {
+            if (--$iterations === 0) {
+                return 'success';
+            }
+
+            throw new \RuntimeException('not yet');
+        });
+
+        $duration = Duration::seconds(microtime(true) - $start);
+
+        self::assertSame('success', $value);
+        self::assertGreaterThanOrEqual(Duration::milliseconds(50), $duration);
+        self::assertLessThanOrEqual(Duration::milliseconds(60), $duration);
+    }
+
+    public function testReturnValueTimeout(): void
+    {
+        $this->expectException(TimeoutException::class);
+
+        await()->atMost(100, Duration::MILLISECONDS)->pollInterval(30)->on(function (): string {
+            throw new \RuntimeException('not yet');
+        });
+    }
 }
diff --git a/tests/DurationTest.php b/tests/DurationTest.php
index dc2693b..2844388 100644
--- a/tests/DurationTest.php
+++ b/tests/DurationTest.php
@@ -11,6 +11,7 @@ class DurationTest extends TestCase
 {
     /**
      * @param int|float $duration
+     *
      * @dataProvider durationsProvider
      */
     public function testFromUnit($duration, string $unit, int $expected): void