diff --git a/src/Controller/CmcEntityController.php b/src/Controller/CmcEntityController.php
index 73c3963..261fcf8 100644
--- a/src/Controller/CmcEntityController.php
+++ b/src/Controller/CmcEntityController.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\coinmarketcap\Controller;
 
+use Drupal\Core\Link;
 use Drupal\Component\Utility\Xss;
 use Drupal\Core\Controller\ControllerBase;
 use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
@@ -25,8 +26,8 @@ class CmcEntityController extends ControllerBase implements ContainerInjectionIn
    *   An array suitable for drupal_render().
    */
   public function revisionShow($cmc_entity_revision) {
-    $cmc_entity = $this->entityManager()->getStorage('cmc_entity')->loadRevision($cmc_entity_revision);
-    $view_builder = $this->entityManager()->getViewBuilder('cmc_entity');
+    $cmc_entity = \Drupal::service('entity_type.manager')->getStorage('cmc_entity')->loadRevision($cmc_entity_revision);
+    $view_builder = \Drupal::service('entity_type.manager')->getViewBuilder('cmc_entity');
 
     return $view_builder->view($cmc_entity);
   }
@@ -41,8 +42,8 @@ class CmcEntityController extends ControllerBase implements ContainerInjectionIn
    *   The page title.
    */
   public function revisionPageTitle($cmc_entity_revision) {
-    $cmc_entity = $this->entityManager()->getStorage('cmc_entity')->loadRevision($cmc_entity_revision);
-    return $this->t('Revision of %title from %date', ['%title' => $cmc_entity->label(), '%date' => format_date($cmc_entity->getRevisionCreationTime())]);
+    $cmc_entity = \Drupal::service('entity_type.manager')->getStorage('cmc_entity')->loadRevision($cmc_entity_revision);
+    return $this->t('Revision of %title from %date', ['%title' => $cmc_entity->label(), '%date' => \Drupal::service('date.formatter')->format($cmc_entity->getRevisionCreationTime())]);
   }
 
   /**
@@ -60,7 +61,7 @@ class CmcEntityController extends ControllerBase implements ContainerInjectionIn
     $langname = $cmc_entity->language()->getName();
     $languages = $cmc_entity->getTranslationLanguages();
     $has_translations = (count($languages) > 1);
-    $cmc_entity_storage = $this->entityManager()->getStorage('cmc_entity');
+    $cmc_entity_storage = \Drupal::service('entity_type.manager')->getStorage('cmc_entity');
 
     $build['#title'] = $has_translations ? $this->t('@langname revisions for %title', ['@langname' => $langname, '%title' => $cmc_entity->label()]) : $this->t('Revisions for %title', ['%title' => $cmc_entity->label()]);
     $header = [$this->t('Revision'), $this->t('Operations')];
@@ -88,10 +89,14 @@ class CmcEntityController extends ControllerBase implements ContainerInjectionIn
         // Use revision link to link to revisions that are not active.
         $date = \Drupal::service('date.formatter')->format($revision->getRevisionCreationTime(), 'short');
         if ($vid != $cmc_entity->getRevisionId()) {
-          $link = $this->l($date, new Url('entity.cmc_entity.revision', ['cmc_entity' => $cmc_entity->id(), 'cmc_entity_revision' => $vid]));
+          // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
+          // Please manually remove the `use LinkGeneratorTrait;` statement from this class.
+          $link = Link::fromTextAndUrl($date, new Url('entity.cmc_entity.revision', ['cmc_entity' => $cmc_entity->id(), 'cmc_entity_revision' => $vid]));
         }
         else {
-          $link = $cmc_entity->link($date);
+          // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
+          // Please confirm that `$cmc_entity` is an instance of `\Drupal\Core\Entity\EntityInterface`. Only the method name and not the class name was checked for this replacement, so this may be a false positive.
+          $link = $cmc_entity->toLink($date)->toString();
         }
 
         $row = [];
diff --git a/src/Form/CmcEntityForm.php b/src/Form/CmcEntityForm.php
index 2f1e094..9c08a46 100644
--- a/src/Form/CmcEntityForm.php
+++ b/src/Form/CmcEntityForm.php
@@ -44,7 +44,7 @@ class CmcEntityForm extends ContentEntityForm {
       $entity->setNewRevision();
 
       // If a new revision is created, save the current user as revision author.
-      $entity->setRevisionCreationTime(REQUEST_TIME);
+      $entity->setRevisionCreationTime(\Drupal::time()->getRequestTime());
       $entity->setRevisionUserId(\Drupal::currentUser()->id());
     }
     else {
@@ -55,13 +55,13 @@ class CmcEntityForm extends ContentEntityForm {
 
     switch ($status) {
       case SAVED_NEW:
-        drupal_set_message($this->t('Created the %label Cmc entity.', [
+        $this->messenger()->addStatus($this->t('Created the %label Cmc entity.', [
           '%label' => $entity->label(),
         ]));
         break;
 
       default:
-        drupal_set_message($this->t('Saved the %label Cmc entity.', [
+        $this->messenger()->addStatus($this->t('Saved the %label Cmc entity.', [
           '%label' => $entity->label(),
         ]));
     }
diff --git a/src/Form/CmcEntityRevisionDeleteForm.php b/src/Form/CmcEntityRevisionDeleteForm.php
index 506af5a..c7a5a60 100644
--- a/src/Form/CmcEntityRevisionDeleteForm.php
+++ b/src/Form/CmcEntityRevisionDeleteForm.php
@@ -73,7 +73,7 @@ class CmcEntityRevisionDeleteForm extends ConfirmFormBase {
    * {@inheritdoc}
    */
   public function getQuestion() {
-    return t('Are you sure you want to delete the revision from %revision-date?', ['%revision-date' => format_date($this->revision->getRevisionCreationTime())]);
+    return t('Are you sure you want to delete the revision from %revision-date?', ['%revision-date' => \Drupal::service('date.formatter')->format($this->revision->getRevisionCreationTime())]);
   }
 
   /**
@@ -107,7 +107,7 @@ class CmcEntityRevisionDeleteForm extends ConfirmFormBase {
     $this->CmcEntityStorage->deleteRevision($this->revision->getRevisionId());
 
     $this->logger('content')->notice('Cmc entity: deleted %title revision %revision.', ['%title' => $this->revision->label(), '%revision' => $this->revision->getRevisionId()]);
-    drupal_set_message(t('Revision from %revision-date of Cmc entity %title has been deleted.', ['%revision-date' => format_date($this->revision->getRevisionCreationTime()), '%title' => $this->revision->label()]));
+    $this->messenger()->addStatus(t('Revision from %revision-date of Cmc entity %title has been deleted.', ['%revision-date' => \Drupal::service('date.formatter')->format($this->revision->getRevisionCreationTime()), '%title' => $this->revision->label()]));
     $form_state->setRedirect(
       'entity.cmc_entity.canonical',
        ['cmc_entity' => $this->revision->id()]
diff --git a/src/Form/CmcEntityRevisionRevertForm.php b/src/Form/CmcEntityRevisionRevertForm.php
index 4142542..711dfa1 100644
--- a/src/Form/CmcEntityRevisionRevertForm.php
+++ b/src/Form/CmcEntityRevisionRevertForm.php
@@ -120,7 +120,7 @@ class CmcEntityRevisionRevertForm extends ConfirmFormBase {
     $this->revision->save();
 
     $this->logger('content')->notice('Cmc entity: reverted %title revision %revision.', ['%title' => $this->revision->label(), '%revision' => $this->revision->getRevisionId()]);
-    drupal_set_message(t('Cmc entity %title has been reverted to the revision from %revision-date.', ['%title' => $this->revision->label(), '%revision-date' => $this->dateFormatter->format($original_revision_timestamp)]));
+    $this->messenger()->addStatus(t('Cmc entity %title has been reverted to the revision from %revision-date.', ['%title' => $this->revision->label(), '%revision-date' => $this->dateFormatter->format($original_revision_timestamp)]));
     $form_state->setRedirect(
       'entity.cmc_entity.version_history',
       ['cmc_entity' => $this->revision->id()]
@@ -141,7 +141,7 @@ class CmcEntityRevisionRevertForm extends ConfirmFormBase {
   protected function prepareRevertedRevision(CmcEntityInterface $revision, FormStateInterface $form_state) {
     $revision->setNewRevision();
     $revision->isDefaultRevision(TRUE);
-    $revision->setRevisionCreationTime(REQUEST_TIME);
+    $revision->setRevisionCreationTime(\Drupal::time()->getRequestTime());
 
     return $revision;
   }
diff --git a/src/Form/CmcEntityRevisionRevertTranslationForm.php b/src/Form/CmcEntityRevisionRevertTranslationForm.php
index 0915711..afb272b 100644
--- a/src/Form/CmcEntityRevisionRevertTranslationForm.php
+++ b/src/Form/CmcEntityRevisionRevertTranslationForm.php
@@ -107,7 +107,7 @@ class CmcEntityRevisionRevertTranslationForm extends CmcEntityRevisionRevertForm
 
     $latest_revision_translation->setNewRevision();
     $latest_revision_translation->isDefaultRevision(TRUE);
-    $revision->setRevisionCreationTime(REQUEST_TIME);
+    $revision->setRevisionCreationTime(\Drupal::time()->getRequestTime());
 
     return $latest_revision_translation;
   }