diff --git a/contrib/crontab.php b/contrib/crontab.php
index 78a26004f..598a406c1 100644
--- a/contrib/crontab.php
+++ b/contrib/crontab.php
@@ -104,31 +104,32 @@
     run ('unlink /tmp/crontab_save');
 });
 
+if (!function_exists('Deployer\parseJob')) {
+    function parseJob ($job) {
+        if (!is_string($job)) {
+            return NULL;
+        }
 
-function parseJob ($job) {
-    if (!is_string($job)) {
-        return NULL;
-    }
+        if (substr ($job, 0, 1) == '#') {
+            return NULL;
+        }
 
-    if (substr ($job, 0, 1) == '#') {
-        return NULL;
-    }
+        $jobData = explode (' ', $job, 6);
 
-    $jobData = explode (' ', $job, 6);
+        if (count ($jobData) != 6) {
+            return NULL;
+        }
 
-    if (count ($jobData) != 6) {
-        return NULL;
+        return [
+            'skey' => md5 ($job),
+            'ckey' => md5 ($jobData['5']),
+            'minute' => $jobData['0'],
+            'hour' => $jobData['1'],
+            'day' => $jobData['2'],
+            'month' => $jobData['3'],
+            'weekday' => $jobData['4'],
+            'cmd' => $jobData['5'],
+        ];
     }
-
-    return [
-        'skey' => md5 ($job),
-        'ckey' => md5 ($jobData['5']),
-        'minute' => $jobData['0'],
-        'hour' => $jobData['1'],
-        'day' => $jobData['2'],
-        'month' => $jobData['3'],
-        'weekday' => $jobData['4'],
-        'cmd' => $jobData['5'],
-    ];
 }
 
diff --git a/test/docker/Dockerfile b/test/docker/Dockerfile
index cbc67ea0e..cebf15a41 100644
--- a/test/docker/Dockerfile
+++ b/test/docker/Dockerfile
@@ -103,6 +103,7 @@ CMD [ "start-servers" ]
 
 FROM ubuntu:20.04 AS provisioned
 RUN apt-get update && apt-get install -y \
+            cron \
             openssh-server \
             sudo \
     && rm -rf /var/lib/apt/lists/*
diff --git a/test/e2e/AbstractE2ETest.php b/test/e2e/AbstractE2ETest.php
index 3669e684f..e0d56cdfb 100644
--- a/test/e2e/AbstractE2ETest.php
+++ b/test/e2e/AbstractE2ETest.php
@@ -14,11 +14,6 @@ abstract class AbstractE2ETest extends TestCase
      */
     protected $tester;
 
-    /**
-     * @var Deployer
-     */
-    protected $deployer;
-
     public static function setUpBeforeClass(): void
     {
         self::cleanUp();
@@ -47,9 +42,9 @@ protected function init(string $recipe): void
         $console->setAutoExit(false);
         $this->tester = new ApplicationTester($console);
 
-        $this->deployer = new Deployer($console);
-        $this->deployer->importer->import($recipe);
-        $this->deployer->init();
-        $this->deployer->config->set('deploy_path', __TEMP_DIR__ . '/{{hostname}}');
+        $deployer = new Deployer($console);
+        $deployer->importer->import($recipe);
+        $deployer->init();
+        $deployer->config->set('deploy_path', __TEMP_DIR__ . '/{{hostname}}');
     }
 }
diff --git a/test/e2e/CrontabE2ETest.php b/test/e2e/CrontabE2ETest.php
new file mode 100644
index 000000000..a73cd2452
--- /dev/null
+++ b/test/e2e/CrontabE2ETest.php
@@ -0,0 +1,79 @@
+<?php declare(strict_types=1);
+namespace e2e;
+
+use function Deployer\set;
+
+class CrontabE2ETest extends AbstractE2ETest
+{
+    private const RECIPE = __DIR__ . '/contrib/crontab.php';
+
+    public function testAddingCrontab(): void {
+
+        $this->init(self::RECIPE);
+
+        set('crontab:jobs', [
+            '* * * * * command-x',
+        ]);
+
+        $this->tester->run([
+            'crontab:sync',
+            '-f' => self::RECIPE,
+            'selector' => 'all',
+        ]);
+
+        self::assertStringContainsString('command-x: NEW', $this->tester->getDisplay());
+
+        $this->init(self::RECIPE);
+
+        set('crontab:jobs', [
+            '* * * * * command-x',
+        ]);
+
+        // Run the crontab:sync again to assert the same job won't be added twice
+        $this->tester->run([
+           'crontab:sync',
+           '-f' => self::RECIPE,
+           'selector' => 'all',
+       ]);
+
+        self::assertStringContainsString('command-x: OK', $this->tester->getDisplay());
+    }
+
+    public function testUpdatingCrontab(): void {
+        $this->init(self::RECIPE);
+
+        set('crontab:jobs', [
+            '1 * * * * command-y',
+        ]);
+
+        $this->tester->run([
+            'crontab:sync',
+            '-f' => self::RECIPE,
+            'selector' => 'all',
+        ]);
+
+        self::assertStringContainsString('command-y: NEW', $this->tester->getDisplay());
+
+        $this->init(self::RECIPE);
+
+        set('crontab:jobs', [
+            '2 * * * * command-y',
+        ]);
+
+        $this->tester->run([
+            'crontab:sync',
+            '-f' => self::RECIPE,
+            'selector' => 'all',
+        ]);
+
+        self::assertStringContainsString('command-y: FIX', $this->tester->getDisplay());
+    }
+
+    protected function tearDown(): void
+    {
+        parent::tearDown();
+
+        $this->tester->run(['crontab-test:truncate', '-f' => self::RECIPE, 'selector' => 'all']);
+    }
+}
+
diff --git a/test/e2e/contrib/crontab.php b/test/e2e/contrib/crontab.php
new file mode 100644
index 000000000..ddfc7f2fb
--- /dev/null
+++ b/test/e2e/contrib/crontab.php
@@ -0,0 +1,18 @@
+<?php declare(strict_types=1);
+namespace Deployer;
+
+require __DIR__ . '/../../../contrib/crontab.php';
+
+host('provisioned.test')
+    ->set('timeout', 300)
+    ->setTag('e2e')
+    ->setRemoteUser('root')
+    ->setSshArguments([
+       '-o UserKnownHostsFile=/dev/null',
+       '-o StrictHostKeyChecking=no',
+    ]);
+
+task('crontab-test:truncate', function() {
+    run ("echo '' > /tmp/crontab_save");
+    run ("{{bin/crontab}} /tmp/crontab_save");
+});