diff --git a/pathauto.install b/pathauto.install
index a8ecabf..0adbc03 100644
--- a/pathauto.install
+++ b/pathauto.install
@@ -200,3 +200,21 @@ function pathauto_update_8100() {
     return implode('</br>', $messages);
   }
 }
+
+/**
+ * Update relationship storage.
+ */
+function pathauto_update_8101() {
+  foreach (\Drupal::configFactory()->listAll('pathauto.pattern.') as $pattern_config_name) {
+    $pattern_config = \Drupal::configFactory()->getEditable($pattern_config_name);
+
+    $relationships = [];
+    foreach ((array) $pattern_config->get('context_definitions') as $context_definition) {
+      $relationships[$context_definition['id']] = ['label' => $context_definition['label']];
+    }
+
+    $pattern_config->clear('context_definitions');
+    $pattern_config->set('relationships', $relationships);
+    $pattern_config->save();
+  }
+}
diff --git a/src/Entity/PathautoPattern.php b/src/Entity/PathautoPattern.php
index c0d8862..321948d 100644
--- a/src/Entity/PathautoPattern.php
+++ b/src/Entity/PathautoPattern.php
@@ -7,16 +7,14 @@
 
 namespace Drupal\pathauto\Entity;
 
+use Drupal\Component\Plugin\Exception\ContextException;
 use Drupal\Core\Condition\ConditionPluginCollection;
 use Drupal\Core\Config\Entity\ConfigEntityBase;
 use Drupal\Core\Entity\EntityStorageInterface;
 use Drupal\Core\Plugin\Context\Context;
-use Drupal\Core\Plugin\Context\ContextDefinition;
-use Drupal\Core\Plugin\Context\ContextInterface;
 use Drupal\Core\Plugin\ContextAwarePluginInterface;
 use Drupal\Core\Plugin\DefaultSingleLazyPluginCollection;
 use Drupal\pathauto\PathautoPatternInterface;
-use Drupal\rules\Context\ContextDefinitionInterface;
 
 /**
  * Defines the Pathauto pattern entity.
@@ -111,11 +109,6 @@ class PathautoPattern extends ConfigEntityBase implements PathautoPatternInterfa
   protected $weight = 0;
 
   /**
-   * @var \Drupal\Core\Plugin\Context\ContextInterface[]|NULL
-   */
-  protected $contexts = NULL;
-
-  /**
    * @var array
    */
   protected $relationships = [];
@@ -219,35 +212,27 @@ class PathautoPattern extends ConfigEntityBase implements PathautoPatternInterfa
   /**
    * {@inheritdoc}
    */
-  protected function getContexts() {
-    if (is_null($this->contexts)) {
-      $this->contexts = $this->getAliasType()->getContexts();
-      foreach ($this->getRelationships() as $definition) {
-        /** @var \Drupal\ctools\TypedDataResolver $resolver */
-        $resolver = \Drupal::service('ctools.typed_data.resolver');
-        /** @var \Drupal\pathauto\Entity\PathautoPattern $entity */
-        $context = $resolver->convertTokenToContext($definition['id'], $this->contexts);
-        $context_definition = $context->getContextDefinition();
-        if (!empty($definition['label'])) {
-          $context_definition->setLabel($definition['label']);
-        }
-        $contexts[$definition['id']] = new Context($context_definition, $context->getContextValue());
-        $this->contexts[$definition['id']] = $contexts[$definition['id']];
+  public function getContexts() {
+    $contexts = $this->getAliasType()->getContexts();
+    foreach ($this->getRelationships() as $token => $definition) {
+      /** @var \Drupal\ctools\TypedDataResolver $resolver */
+      $resolver = \Drupal::service('ctools.typed_data.resolver');
+      /** @var \Drupal\pathauto\Entity\PathautoPattern $entity */
+      $context = $resolver->convertTokenToContext($token, $contexts);
+      $context_definition = $context->getContextDefinition();
+      if (!empty($definition['label'])) {
+        $context_definition->setLabel($definition['label']);
       }
+      $contexts[$token] = $context;
     }
-    return $this->contexts;
+    return $contexts;
   }
 
   /**
    * {@inheritdoc}
    */
   public function hasRelationship($token) {
-    foreach ($this->getRelationships() as $key => $definition) {
-      if ($definition['id'] == $token) {
-        return TRUE;
-      }
-    }
-    return FALSE;
+    return isset($this->relationships[$token]);
   }
 
   /**
@@ -255,11 +240,9 @@ class PathautoPattern extends ConfigEntityBase implements PathautoPatternInterfa
    */
   public function addRelationship($token, $label = NULL) {
     if (!$this->hasRelationship($token)) {
-      $this->relationships[] = [
-        'id' => $token,
+      $this->relationships[$token] = [
         'label' => $label,
       ];
-      $this->contexts = NULL;
     }
     return $this;
   }
@@ -269,11 +252,9 @@ class PathautoPattern extends ConfigEntityBase implements PathautoPatternInterfa
    */
   public function replaceRelationship($token, $label) {
     if ($this->hasRelationship($token)) {
-      $this->relationships[] = [
-        'id' => $token,
+      $this->relationships[$token] = [
         'label' => $label,
       ];
-      $this->contexts = NULL;
     }
     return $this;
   }
@@ -282,12 +263,7 @@ class PathautoPattern extends ConfigEntityBase implements PathautoPatternInterfa
    * {@inheritdoc}
    */
   public function removeRelationship($token) {
-    foreach ($this->getRelationships() as $key => $definition) {
-      if ($definition['id'] == $token) {
-        unset($this->relationships[$key]);
-        $this->contexts = NULL;
-      }
-    }
+    unset($this->relationships[$token]);
     return $this;
   }
 
@@ -352,22 +328,19 @@ class PathautoPattern extends ConfigEntityBase implements PathautoPatternInterfa
       // Set the context object on our Alias plugin before retrieving contexts.
       $this->getAliasType()->setContextValue($keys[0], $object);
       /** @var \Drupal\Core\Plugin\Context\ContextInterface[] $base_contexts */
-      $base_contexts = $this->getAliasType()->getContexts();
-      $contexts = [];
-      foreach ($base_contexts as $context_id => $base_context) {
-        $contexts[$context_id] = new Context($base_context->getContextDefinition(), $object);
-      }
-      /** @var \Drupal\ctools\TypedDataResolver $resolver */
-      $resolver = \Drupal::service('ctools.typed_data.resolver');
-      foreach ($this->getContexts() as $token => $context) {
-        $contexts[$token] = $resolver->convertTokenToContext($token, $contexts);
-      }
+      $contexts = $this->getContexts();
       /** @var \Drupal\Core\Plugin\Context\ContextHandler $context_handler */
       $context_handler = \Drupal::service('context.handler');
       $conditions = $this->getSelectionConditions();
       foreach ($conditions as $condition) {
         if ($condition instanceof ContextAwarePluginInterface) {
-          $context_handler->applyContextMapping($condition, $contexts);
+          try {
+            $context_handler->applyContextMapping($condition, $contexts);
+          }
+          catch (ContextException $e) {
+            watchdog_exception('pathauto', $e);
+            return FALSE;
+          }
         }
         $result = $condition->execute();
         if ($this->getSelectionLogic() == 'and' && !$result) {
diff --git a/src/PathautoPatternInterface.php b/src/PathautoPatternInterface.php
index 0597187..9493dca 100644
--- a/src/PathautoPatternInterface.php
+++ b/src/PathautoPatternInterface.php
@@ -60,33 +60,69 @@ interface PathautoPatternInterface extends ConfigEntityInterface {
   public function setWeight($weight);
 
   /**
+   * Returns the contexts of this pattern.
+   *
+   * @return \Drupal\Core\Plugin\Context\ContextInterface[]
+   */
+  public function getContexts();
+
+  /**
+   * Returns whether a relationship exists.
+   *
+   * @param string $token
+   *   Relationship identifier.
+   *
    * @return bool
+   *   TRUE if the relationship exists, FALSE otherwise.
    */
   public function hasRelationship($token);
 
   /**
+   * Adds a relationship.
+   *
+   * The relationship will not be changed if it already exists.
+   *
    * @param string $token
-   * @param \Drupal\Core\Plugin\Context\ContextInterface $context
+   *   Relationship identifier.
+   * @param string|null $label
+   *   (optional) A label, will use the label of the referenced context if not
+   *   provided.
    *
    * @return $this
    */
   public function addRelationship($token, $label = NULL);
 
   /**
+   * Replaces a relationship.
+   *
+   * Only already existing relationships are updated.
+   *
    * @param string $token
-   * @param \Drupal\Core\Plugin\Context\ContextInterface $context
+   *   Relationship identifier.
+   * @param string|null $label
+   *   (optional) A label, will use the label of the referenced context if not
+   *   provided.
    *
    * @return $this
    */
   public function replaceRelationship($token, $label);
 
   /**
+   * Removes a relationship.
+   *
    * @param string $token
+   *   Relationship identifier.
    *
    * @return $this
    */
   public function removeRelationship($token);
 
+  /**
+   * Returns a list of relationships.
+   *
+   * @return array
+   *   Relationships keyed by ID, a relationship is an array with a label key.
+   */
   public function getRelationships();
 
   /**