diff --git a/lib/Worker/Internal/Job.php b/lib/Worker/Internal/Job.php
index 75d3f3f..d6269cc 100644
--- a/lib/Worker/Internal/Job.php
+++ b/lib/Worker/Internal/Job.php
@@ -2,7 +2,6 @@
 
 namespace Amp\Parallel\Worker\Internal;
 
-use Amp\Parallel\Worker\Environment;
 use Amp\Parallel\Worker\Task;
 
 /** @internal */
@@ -25,11 +24,7 @@ class Job {
     public function getTask(): Task {
         // Classes that cannot be autoloaded will be unserialized as an instance of __PHP_Incomplete_Class.
         if ($this->task instanceof \__PHP_Incomplete_Class) {
-            return new class implements Task {
-                public function run(Environment $environment) {
-                    throw new \Error(\sprintf("Classes implementing %s must be autoloadable by the Composer autoloader", Task::class));
-                }
-            };
+            throw new \Error(\sprintf("Classes implementing %s must be autoloadable by the Composer autoloader", Task::class));
         }
 
         return $this->task;
diff --git a/lib/Worker/TaskRunner.php b/lib/Worker/TaskRunner.php
index 403938e..5ca7823 100644
--- a/lib/Worker/TaskRunner.php
+++ b/lib/Worker/TaskRunner.php
@@ -37,17 +37,18 @@ class TaskRunner {
         $job = yield $this->channel->receive();
 
         while ($job instanceof Internal\Job) {
-            call([$job->getTask(), 'run'], $this->environment)->onResolve(function ($exception, $value) use ($job) {
-                if ($exception) {
-                    $result = new Internal\TaskFailure($job->getId(), $exception);
-                } else {
-                    $result = new Internal\TaskSuccess($job->getId(), $value);
-                }
+            try {
+                $result = yield call([$job->getTask(), "run"], $this->environment);
+                $result = new Internal\TaskSuccess($job->getId(), $result);
+            } catch (\Throwable $exception) {
+                $result = new Internal\TaskFailure($job->getId(), $exception);
+            }
 
-                $this->channel->send($result);
-            });
+            $job = null; // Free memory from last job.
 
-            unset($job); // Free memory from last job.
+            yield $this->channel->send($result);
+
+            $result = null; // Free memory from last result.
 
             $job = yield $this->channel->receive();
         }
diff --git a/test/Worker/AbstractWorkerTest.php b/test/Worker/AbstractWorkerTest.php
index 6ddc156..07d2343 100644
--- a/test/Worker/AbstractWorkerTest.php
+++ b/test/Worker/AbstractWorkerTest.php
@@ -93,7 +93,7 @@ abstract class AbstractWorkerTest extends TestCase {
                 $worker->enqueue(new TestTask(72, 100))
             ];
 
-            $expected = [72, 42, 56];
+            $expected = [42, 56, 72];
             foreach ($promises as $promise) {
                 $promise->onResolve(function ($e, $v) use (&$expected) {
                     $this->assertSame(\array_shift($expected), $v);