diff --git a/lib/API/JSON/v1/CustomFields.php b/lib/API/JSON/v1/CustomFields.php
index 4e1628393a..aa06869a00 100644
--- a/lib/API/JSON/v1/CustomFields.php
+++ b/lib/API/JSON/v1/CustomFields.php
@@ -32,7 +32,7 @@ class CustomFields extends APIEndpoint {
   }
 
   public function getAll() {
-    $collection = $this->customFieldsRepository->findBy([], ['created_at' => 'asc']);
+    $collection = $this->customFieldsRepository->findBy([], ['createdAt' => 'asc']);
     return $this->successResponse($this->customFieldsResponseBuilder->buildBatch($collection));
   }
 
diff --git a/lib/Config/Populator.php b/lib/Config/Populator.php
index 5c27a03f84..58a7d2d3c4 100644
--- a/lib/Config/Populator.php
+++ b/lib/Config/Populator.php
@@ -314,7 +314,7 @@ class Populator {
   private function createOrUpdateUserFlag($userId, $name, $value) {
     $userFlagsRepository = \MailPoet\DI\ContainerWrapper::getInstance(WP_DEBUG)->get(UserFlagsRepository::class);
     $flag = $userFlagsRepository->findOneBy([
-      'user_id' => $userId,
+      'userId' => $userId,
       'name' => $name,
     ]);
 
diff --git a/lib/Cron/Workers/SendingQueue/Tasks/Mailer.php b/lib/Cron/Workers/SendingQueue/Tasks/Mailer.php
index 0817e2df3d..cceb83eaac 100644
--- a/lib/Cron/Workers/SendingQueue/Tasks/Mailer.php
+++ b/lib/Cron/Workers/SendingQueue/Tasks/Mailer.php
@@ -45,7 +45,7 @@ class Mailer {
   }
 
   public function getProcessingMethod() {
-    return ($this->mailer->mailer_config['method'] === MailerFactory::METHOD_MAILPOET) ?
+    return ($this->mailer->mailerConfig['method'] === MailerFactory::METHOD_MAILPOET) ?
       'bulk' :
       'individual';
   }
@@ -58,7 +58,7 @@ class Mailer {
     if ($this->getProcessingMethod() === 'individual') {
       throw new \LogicException('Trying to send a batch with individual processing method');
     }
-    return $this->mailer->mailer_instance->send(
+    return $this->mailer->mailerInstance->send(
       $preparedNewsletters,
       $preparedSubscribers,
       $extraParams
@@ -69,7 +69,7 @@ class Mailer {
     if ($this->getProcessingMethod() === 'bulk') {
       throw new \LogicException('Trying to send an individual email with a bulk processing method');
     }
-    return $this->mailer->mailer_instance->send(
+    return $this->mailer->mailerInstance->send(
       $preparedNewsletter,
       $preparedSubscriber,
       $extraParams
diff --git a/lib/Cron/Workers/StatsNotifications/StatsNotificationsRepository.php b/lib/Cron/Workers/StatsNotifications/StatsNotificationsRepository.php
index 7262df588c..d3cf3a0644 100644
--- a/lib/Cron/Workers/StatsNotifications/StatsNotificationsRepository.php
+++ b/lib/Cron/Workers/StatsNotifications/StatsNotificationsRepository.php
@@ -40,11 +40,11 @@ class StatsNotificationsRepository extends Repository {
       ->addSelect('tasks')
       ->addSelect('n')
       ->addOrderBy('tasks.priority')
-      ->addOrderBy('tasks.updated_at')
-      ->where('tasks.deleted_at IS NULL')
+      ->addOrderBy('tasks.updatedAt')
+      ->where('tasks.deletedAt IS NULL')
       ->andWhere('tasks.status = :status')
       ->setParameter('status', ScheduledTaskEntity::STATUS_SCHEDULED)
-      ->andWhere('tasks.scheduled_at < :date')
+      ->andWhere('tasks.scheduledAt < :date')
       ->setParameter('date', $date)
       ->andWhere('tasks.type = :workerType')
       ->setParameter('workerType', Worker::TASK_TYPE);
diff --git a/lib/Newsletter/NewslettersRepository.php b/lib/Newsletter/NewslettersRepository.php
index 2a125bfb87..10d69a7dfa 100644
--- a/lib/Newsletter/NewslettersRepository.php
+++ b/lib/Newsletter/NewslettersRepository.php
@@ -28,7 +28,7 @@ class NewslettersRepository extends Repository {
       ->from(NewsletterEntity::class, 'n')
       ->where('n.status = :status')
       ->setParameter(':status', NewsletterEntity::STATUS_ACTIVE)
-      ->andWhere('n.deleted_at is null')
+      ->andWhere('n.deletedAt is null')
       ->andWhere('n.type IN (:types)')
       ->setParameter('types', $types)
       ->orderBy('n.subject')
diff --git a/lib/Newsletter/Statistics/NewsletterStatisticsRepository.php b/lib/Newsletter/Statistics/NewsletterStatisticsRepository.php
index ca7b7b87aa..ad6cd54a30 100644
--- a/lib/Newsletter/Statistics/NewsletterStatisticsRepository.php
+++ b/lib/Newsletter/Statistics/NewsletterStatisticsRepository.php
@@ -25,7 +25,7 @@ class NewsletterStatisticsRepository extends Repository {
         ->createQueryBuilder('n')
         ->join('n.queues', 'q')
         ->join('q.task', 't')
-        ->select('SUM(q.count_processed)')
+        ->select('SUM(q.countProcessed)')
         ->where('t.status = :status')
         ->setParameter('status', ScheduledTaskEntity::STATUS_COMPLETED)
         ->andWhere('q.newsletter = :newsletter')
@@ -78,7 +78,7 @@ class NewsletterStatisticsRepository extends Repository {
     try {
       $qb = $this->entityManager
         ->createQueryBuilder();
-      return $qb->select('COUNT(DISTINCT stats.subscriber_id) as cnt')
+      return $qb->select('COUNT(DISTINCT stats.subscriberId) as cnt')
         ->from($statisticsEntityName, 'stats')
         ->where('stats.newsletter = :newsletter')
         ->setParameter('newsletter', $newsletter)
diff --git a/lib/Router/Endpoints/Track.php b/lib/Router/Endpoints/Track.php
index 220c842e8f..071555e9d3 100644
--- a/lib/Router/Endpoints/Track.php
+++ b/lib/Router/Endpoints/Track.php
@@ -62,8 +62,8 @@ class Track {
       $data->queue = SendingTask::createFromQueue($data->queue);
     }
     $data->subscriber = Subscriber::findOne($data->subscriberId) ?: null;
-    $data->newsletter = (!empty($data->queue->newsletter_id)) ?
-      Newsletter::findOne($data->queue->newsletter_id) :
+    $data->newsletter = (!empty($data->queue->newsletterId)) ?
+      Newsletter::findOne($data->queue->newsletterId) :
       false;
     if (!empty($data->linkHash)) {
       $data->link = NewsletterLink::where('hash', $data->linkHash)
diff --git a/lib/Settings/UserFlagsController.php b/lib/Settings/UserFlagsController.php
index 16f167c411..fb57f217fc 100644
--- a/lib/Settings/UserFlagsController.php
+++ b/lib/Settings/UserFlagsController.php
@@ -44,7 +44,7 @@ class UserFlagsController {
   public function set($name, $value) {
     $currentUserId = WPFunctions::get()->getCurrentUserId();
     $flag = $this->userFlagsRepository->findOneBy([
-      'user_id' => $currentUserId,
+      'userId' => $currentUserId,
       'name' => $name,
     ]);
 
@@ -65,7 +65,7 @@ class UserFlagsController {
   public function delete($name) {
     $currentUserId = WPFunctions::get()->getCurrentUserId();
     $flag = $this->userFlagsRepository->findOneBy([
-      'user_id' => $currentUserId,
+      'userId' => $currentUserId,
       'name' => $name,
     ]);
 
@@ -83,7 +83,7 @@ class UserFlagsController {
 
   private function load() {
     $currentUserId = WPFunctions::get()->getCurrentUserId();
-    $flags = $this->userFlagsRepository->findBy(['user_id' => $currentUserId]);
+    $flags = $this->userFlagsRepository->findBy(['userId' => $currentUserId]);
     $this->data = [];
     foreach ($flags as $flag) {
       $this->data[$flag->getName()] = $flag->getValue();
diff --git a/lib/Subscribers/SubscribersRepository.php b/lib/Subscribers/SubscribersRepository.php
index eb17d8cb61..f5de560c70 100644
--- a/lib/Subscribers/SubscribersRepository.php
+++ b/lib/Subscribers/SubscribersRepository.php
@@ -25,7 +25,7 @@ class SubscribersRepository extends Repository {
       ->createQueryBuilder()
       ->select('count(n.id)')
       ->from(SubscriberEntity::class, 'n')
-      ->where('n.deleted_at IS NULL AND n.status IN (:statuses)')
+      ->where('n.deletedAt IS NULL AND n.status IN (:statuses)')
       ->setParameter('statuses', [
         SubscriberEntity::STATUS_SUBSCRIBED,
         SubscriberEntity::STATUS_UNCONFIRMED,
diff --git a/lib/Subscription/Pages.php b/lib/Subscription/Pages.php
index 6425e866e3..052a39d453 100644
--- a/lib/Subscription/Pages.php
+++ b/lib/Subscription/Pages.php
@@ -132,10 +132,10 @@ class Pages {
     $subscriberData = $this->subscriber->getUnconfirmedData();
 
     $this->subscriber->status = Subscriber::STATUS_SUBSCRIBED;
-    $this->subscriber->confirmed_ip = Helpers::getIP();
+    $this->subscriber->confirmedIp = Helpers::getIP();
     $this->subscriber->setExpr('confirmed_at', 'NOW()');
     $this->subscriber->setExpr('last_subscribed_at', 'NOW()');
-    $this->subscriber->unconfirmed_data = null;
+    $this->subscriber->unconfirmedData = null;
     $this->subscriber->save();
 
     if ($this->subscriber->getErrors() === false) {
diff --git a/lib/Tasks/Sending.php b/lib/Tasks/Sending.php
index c67edb3185..c9406d92d1 100644
--- a/lib/Tasks/Sending.php
+++ b/lib/Tasks/Sending.php
@@ -200,9 +200,9 @@ class Sending {
   }
 
   public function updateCount() {
-    $this->queue->count_processed = ScheduledTaskSubscriber::getProcessedCount($this->task->id);
-    $this->queue->count_to_process = ScheduledTaskSubscriber::getUnprocessedCount($this->task->id);
-    $this->queue->count_total = $this->queue->count_processed + $this->queue->count_to_process;
+    $this->queue->countProcessed = ScheduledTaskSubscriber::getProcessedCount($this->task->id);
+    $this->queue->countToProcess = ScheduledTaskSubscriber::getUnprocessedCount($this->task->id);
+    $this->queue->countTotal = $this->queue->countProcessed + $this->queue->countToProcess;
     return $this->queue->save();
   }
 
diff --git a/tests/DataFactories/UserFlags.php b/tests/DataFactories/UserFlags.php
index 8c8dc8b2f2..da6cb8d14f 100644
--- a/tests/DataFactories/UserFlags.php
+++ b/tests/DataFactories/UserFlags.php
@@ -29,7 +29,7 @@ class UserFlags {
 
   public function withFlag($name, $value) {
     $userFlag = $this->userFlagsRepository->findOneBy([
-      'user_id' => $this->userId,
+      'userId' => $this->userId,
       'name' => $name,
     ]);
 
diff --git a/tests/integration/Settings/UserFlagsControllerTest.php b/tests/integration/Settings/UserFlagsControllerTest.php
index dee79ae7e2..86a3b08b3b 100644
--- a/tests/integration/Settings/UserFlagsControllerTest.php
+++ b/tests/integration/Settings/UserFlagsControllerTest.php
@@ -68,7 +68,7 @@ class UserFlagsControllerTest extends \MailPoetTest {
     $this->userFlags->set('flag_1', 'updated_value');
     expect($this->userFlags->get('flag_1'))->equals('updated_value');
     $flag = $this->userFlagsRepository->findOneBy([
-      'user_id' => $this->currentUserId,
+      'userId' => $this->currentUserId,
       'name' => 'flag_1',
     ]);
     expect($flag->getValue())->equals('updated_value');
@@ -79,7 +79,7 @@ class UserFlagsControllerTest extends \MailPoetTest {
     $this->userFlags->delete('flag_1');
     expect($this->userFlags->get('flag_1'))->equals('default_value_1');
     $flag = $this->userFlagsRepository->findOneBy([
-      'user_id' => $this->currentUserId,
+      'userId' => $this->currentUserId,
       'name' => 'flag_1',
     ]);
     expect($flag)->null();
@@ -102,7 +102,7 @@ class UserFlagsControllerTest extends \MailPoetTest {
 
   private function updateUserFlag($userId, $name, $value) {
     $flag = $this->userFlagsRepository->findOneBy([
-      'user_id' => $userId,
+      'userId' => $userId,
       'name' => $name,
     ]);
     if (!$flag) {