Use new package

composer.json

@@ -27,13 +27,14 @@
     "drupal/prepopulate" : "^2.2",
     "drupal/search_api": "^1.8",
     "drupal/token" : "^1.3",
-    "islandora/crayfish-commons": "dev-upgrade-5.4-symfony",
+    "islandora/chullo": "^1.3",
+    "islandora/fedora-entity-mapper": "1.x-dev",
     "islandora/jsonld": "^2",
     "stomp-php/stomp-php": "4.* || ^5"
   },
   "require-dev": {
     "phpunit/phpunit": "^6",
-    "squizlabs/php_codesniffer": "2.7.1",
+    "squizlabs/php_codesniffer": "^2.7.1",
     "drupal/coder": "*",
     "sebastian/phpcpd": "*"
   },

islandora.services.yml

@@ -56,7 +56,7 @@ services:
     class: Drupal\islandora\IslandoraUtils
     arguments: ['@entity_type.manager', '@entity_field.manager', '@context.manager', '@flysystem_factory', '@language_manager']
   islandora.entity_mapper:
-    class: Islandora\Crayfish\Commons\EntityMapper\EntityMapper
+    class: Islandora\EntityMapper\EntityMapper
   islandora.stomp.auth_header_listener:
     class: Drupal\islandora\EventSubscriber\StompHeaderEventSubscriber
     arguments: ['@jwt.authentication.jwt']