diff --git a/src/core/Thing.ts b/src/core/Thing.ts
index 82e4fd92..6ecf2bee 100644
--- a/src/core/Thing.ts
+++ b/src/core/Thing.ts
@@ -23,29 +23,31 @@ import {SCUuid} from './types/UUID';
 /**
  * Types a thing can be
  */
-export type SCThingTypes = 'article'
-  | 'academic event'
-  | 'book'
-  | 'building'
-  | 'catalog'
-  | 'course of studies'
-  | 'date series'
-  | 'diff'
-  | 'dish'
-  | 'favorite'
-  | 'floor'
-  | 'message'
-  | 'offer'
-  | 'organization'
-  | 'person'
-  | 'point of interest'
-  | 'room'
-  | 'semester'
-  | 'setting'
-  | 'sport course'
-  | 'ticket'
-  | 'tour'
-  | 'video';
+export enum SCThingType {
+  AcademicEvent = 'academic event',
+  Article = 'article',
+  Book = 'book',
+  Building = 'building',
+  Catalog = 'catalog',
+  CourseOfStudies = 'course of studies',
+  DateSeries = 'date series',
+  Diff = 'diff',
+  Dish = 'dish',
+  Favorite = 'favorite',
+  Floor = 'floor',
+  Message = 'message',
+  Offer = 'offer', // Currently not in use
+  Organization = 'organization',
+  Person = 'person',
+  PointOfInterest = 'point of interest',
+  Room = 'room',
+  Semester = 'semester',
+  Setting = 'setting',
+  SportCourse = 'sport course',
+  Ticket = 'ticket',
+  Tour = 'tour',
+  Video = 'video',
+}
 
 /**
  * A thing
@@ -84,7 +86,7 @@ export interface SCThing {
   /**
    * Type of the thing
    */
-  type: SCThingTypes;
+  type: string;
   /**
    * Universally unique identifier of the thing
    */
diff --git a/src/core/protocol/routes/bulk/BulkRequest.ts b/src/core/protocol/routes/bulk/BulkRequest.ts
index c53a113f..6e7f1a94 100644
--- a/src/core/protocol/routes/bulk/BulkRequest.ts
+++ b/src/core/protocol/routes/bulk/BulkRequest.ts
@@ -13,7 +13,6 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCAbstractRoute} from '../../../Route';
-import {SCThingTypes} from '../../../Thing';
 import {SCISO8601Date} from '../../../types/Time';
 
 /**
@@ -45,9 +44,11 @@ export interface SCBulkParameters {
   source: string;
 
   /**
-   * Type of things that are indexed in this bulk
+   * Type of things that are indexed in this bulk.
+   * 
+   * String is an element of the SCThingType enumeration.
    */
-  type: SCThingTypes;
+  type: string;
 }
 
 /**
diff --git a/src/core/things/AcademicEvent.ts b/src/core/things/AcademicEvent.ts
index 4c642e62..63ccdce1 100644
--- a/src/core/things/AcademicEvent.ts
+++ b/src/core/things/AcademicEvent.ts
@@ -18,14 +18,9 @@ import {
   SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 
-/**
- * Type of an academic event
- */
-export type SCAcademicEventType = 'academic event';
-
 /**
  * An academic event without references
  */
@@ -51,7 +46,7 @@ export interface SCAcademicEventWithoutReferences
   /**
    * Type of an academic event
    */
-  type: SCAcademicEventType;
+  type: SCThingType.AcademicEvent;
 }
 
 export interface SCAcademicEvent extends SCEvent, SCAcademicEventWithoutReferences {
@@ -63,7 +58,7 @@ export interface SCAcademicEvent extends SCEvent, SCAcademicEventWithoutReferenc
   /**
    * Type of an academic event
    */
-  type: SCAcademicEventType;
+  type: SCThingType.AcademicEvent;
 }
 
 /**
diff --git a/src/core/things/Article.ts b/src/core/things/Article.ts
index ae7e8f8e..6bc3f044 100644
--- a/src/core/things/Article.ts
+++ b/src/core/things/Article.ts
@@ -22,14 +22,9 @@ import {
   SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 
-/**
- * Type of an article
- */
-export type SCArticleType = 'article';
-
 /**
  * An article without references
  */
@@ -50,7 +45,7 @@ export interface SCArticleWithoutReferences
   /**
    * Type of an article
    */
-  type: SCArticleType;
+  type: SCThingType.Article;
 }
 
 /**
@@ -65,7 +60,7 @@ export interface SCArticle extends SCCreativeWork, SCArticleWithoutReferences {
   /**
    * Type of an article
    */
-  type: SCArticleType;
+  type: SCThingType.Article;
 }
 
 /**
diff --git a/src/core/things/Book.ts b/src/core/things/Book.ts
index 47229740..27a6142f 100644
--- a/src/core/things/Book.ts
+++ b/src/core/things/Book.ts
@@ -18,15 +18,10 @@ import {
   SCCreativeWorkWithoutReferences,
 } from '../base/CreativeWork';
 import {SCThingWithCategoriesTranslatableProperties} from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 import {SCPersonWithoutReferences} from './Person';
 
-/**
- * Type of a book
- */
-export type SCBookType = 'book';
-
 /**
  * A book without references
  */
@@ -54,7 +49,7 @@ export interface SCBookWithoutReferences extends SCCreativeWorkWithoutReferences
   /**
    * Type of a book
    */
-  type: SCBookType;
+  type: SCThingType.Book;
 }
 
 /**
@@ -74,7 +69,7 @@ export interface SCBook extends SCCreativeWork, SCBookWithoutReferences {
   /**
    * Type of a book
    */
-  type: SCBookType;
+  type: SCThingType.Book;
 }
 
 /**
diff --git a/src/core/things/Building.ts b/src/core/things/Building.ts
index c7c3b668..fa9acf5a 100644
--- a/src/core/things/Building.ts
+++ b/src/core/things/Building.ts
@@ -18,11 +18,9 @@ import {
   SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 
-export type SCBuildingType = 'building';
-
 export type SCBuildingCategories =
   'cafe'
   | 'education'
@@ -55,10 +53,14 @@ export interface SCBuildingWithoutReferences
   /**
    * Type of the building
    */
-  type: SCBuildingType;
+  type: SCThingType.Building;
 }
 
 export interface SCBuilding extends SCBuildingWithoutReferences {
+  /**
+   * Type of the building
+   */
+  type: SCThingType.Building;
 }
 
 /**
diff --git a/src/core/things/Catalog.ts b/src/core/things/Catalog.ts
index 5f6c1434..2465ccec 100644
--- a/src/core/things/Catalog.ts
+++ b/src/core/things/Catalog.ts
@@ -14,12 +14,7 @@
  */
 import {SCAcademicTermWithoutReferences} from '../base/AcademicTerm';
 import {SCThingWithCategoriesSpecificValues, SCThingWithCategoriesWithoutReferences} from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
-
-/**
- * Type of a catalog
- */
-export type SCCatalogType = 'catalog';
+import {SCThingMeta, SCThingType} from '../Thing';
 
 /**
  * A catalog without references
@@ -37,7 +32,7 @@ export interface SCCatalogWithoutReferences
   /**
    * Type of a catalog
    */
-  type: SCCatalogType;
+  type: SCThingType.Catalog;
 }
 
 /**
@@ -58,6 +53,11 @@ export interface SCCatalog extends SCCatalogWithoutReferences {
    * An array of catalogs from the 'level 0' (root) catalog to the direct parent
    */
   superCatalogs?: SCCatalogWithoutReferences[];
+
+  /**
+   * Type of a catalog
+   */
+  type: SCThingType.Catalog;
 }
 
 /**
diff --git a/src/core/things/CourseOfStudies.ts b/src/core/things/CourseOfStudies.ts
index 92422c71..3cbe8123 100644
--- a/src/core/things/CourseOfStudies.ts
+++ b/src/core/things/CourseOfStudies.ts
@@ -16,16 +16,11 @@ import {SCAcademicDegree} from '../base/AcademicDegree';
 import {SCAcademicPriceGroup,
         SCThingThatCanBeOffered,
         SCThingThatCanBeOfferedTranslatableProperties} from '../base/ThingThatCanBeOffered';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCLanguage, SCTranslations} from '../types/i18n';
 import {SCDateSeriesWithoutReferences} from './DateSeries';
 import {SCOrganization} from './Organization';
 
-/**
- * Type of a course of studies
- */
-export type SCCourseOfStudiesType = 'course of studies';
-
 /**
  * A course of studies without references
  */
@@ -61,7 +56,7 @@ export interface SCCourseOfStudiesWithoutReferences extends
   /**
    * Type of the course of studies
    */
-  type: SCCourseOfStudiesType;
+  type: SCThingType.CourseOfStudies;
 }
 
 /**
@@ -83,6 +78,11 @@ export interface SCCourseOfStudies extends SCCourseOfStudiesWithoutReferences {
    * Dates at which the course of studies is planned to start
    */
   startDates?: SCDateSeriesWithoutReferences[];
+
+  /**
+   * Type of the course of studies
+   */
+  type: SCThingType.CourseOfStudies;
 }
 
 export interface SCCourseOfStudiesTranslatableProperties
diff --git a/src/core/things/DateSeries.ts b/src/core/things/DateSeries.ts
index 1051e41e..87046c4b 100644
--- a/src/core/things/DateSeries.ts
+++ b/src/core/things/DateSeries.ts
@@ -18,18 +18,13 @@ import {
   SCThingThatCanBeOffered,
   SCThingThatCanBeOfferedTranslatableProperties,
 } from '../base/ThingThatCanBeOffered';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 import {SCISO8601Date, SCISO8601Duration} from '../types/Time';
 import {SCAcademicEventWithoutReferences} from './AcademicEvent';
 import {SCPersonWithoutReferences} from './Person';
 import {SCSportCourseWithoutReferences} from './SportCourse';
 
-/**
- * Type of a date series
- */
-export type SCDateSeriesType = 'date series';
-
 /**
  * Price groups for sport courses
  */
@@ -73,7 +68,7 @@ export interface SCDateSeriesWithoutReferences
   /**
    * Type of a date series
    */
-  type: SCDateSeriesType;
+  type: SCThingType.DateSeries;
 }
 
 /**
@@ -99,7 +94,7 @@ export interface SCDateSeries extends SCDateSeriesWithoutReferences, SCThingInPl
   /**
    * Type of a date series
    */
-  type: SCDateSeriesType;
+  type: SCThingType.DateSeries;
 }
 
 /**
diff --git a/src/core/things/Diff.ts b/src/core/things/Diff.ts
index e5cb9534..28036a17 100644
--- a/src/core/things/Diff.ts
+++ b/src/core/things/Diff.ts
@@ -13,14 +13,9 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCThingsWithoutDiff} from '../Classes';
-import {SCThing, SCThingMeta} from '../Thing';
+import {SCThing, SCThingMeta, SCThingType} from '../Thing';
 import {SCISO8601Date} from '../types/Time';
 
-/**
- * Type of a diff
- */
-export type SCDiffType = 'diff';
-
 /**
  * A diff without references
  */
@@ -43,7 +38,7 @@ export interface SCDiffWithoutReferences extends SCThing {
   /**
    * Type of a diff
    */
-  type: SCDiffType;
+  type: SCThingType.Diff;
 }
 
 /**
@@ -54,6 +49,11 @@ export interface SCDiff extends SCDiffWithoutReferences {
    * Original object the diff was generated on
    */
   object: SCThingsWithoutDiff;
+
+  /**
+   * Type of a diff
+   */
+  type: SCThingType.Diff;
 }
 
 /**
diff --git a/src/core/things/Dish.ts b/src/core/things/Dish.ts
index d05218d3..983565e7 100644
--- a/src/core/things/Dish.ts
+++ b/src/core/things/Dish.ts
@@ -23,14 +23,9 @@ import {
   SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 
-/**
- * Type of a dish
- */
-export type SCDishType = 'dish';
-
 /**
  * A dish without references
  */
@@ -66,7 +61,7 @@ export interface SCDishWithoutReferences
   /**
    * Type of a dish
    */
-  type: SCDishType;
+  type: SCThingType.Dish;
 }
 
 /**
@@ -86,7 +81,7 @@ export interface SCDish extends SCDishWithoutReferences, SCThingInPlace {
   /**
    * Type of a dish
    */
-  type: SCDishType;
+  type: SCThingType.Dish;
 }
 
 export interface SCDishTranslatableProperties
diff --git a/src/core/things/Favorite.ts b/src/core/things/Favorite.ts
index 63a2acab..e2715660 100644
--- a/src/core/things/Favorite.ts
+++ b/src/core/things/Favorite.ts
@@ -12,7 +12,7 @@
  * You should have received a copy of the GNU General Public License along with
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
-import {SCThing, SCThingMeta} from '../Thing';
+import {SCThing, SCThingMeta, SCThingType} from '../Thing';
 import {SCISO8601Date} from '../types/Time';
 import {SCAcademicEventWithoutReferences} from './AcademicEvent';
 import {SCArticleWithoutReferences} from './Article';
@@ -23,11 +23,6 @@ import {SCPointOfInterestWithoutReferences} from './PointOfInterest';
 import {SCRoomWithoutReferences} from './Room';
 import {SCSportCourseWithoutReferences} from './SportCourse';
 
-/**
- * Type of a favorite
- */
-export type SCFavoriteType = 'favorite';
-
 /**
  * A favorite without references
  */
@@ -50,7 +45,7 @@ export interface SCFavoriteWithoutReferences extends SCThing {
   /**
    * Type of a favorite
    */
-  type: SCFavoriteType;
+  type: SCThingType.Favorite;
 }
 
 /**
@@ -69,6 +64,11 @@ export interface SCFavorite extends SCFavoriteWithoutReferences {
     | SCPointOfInterestWithoutReferences
     | SCRoomWithoutReferences
     | SCSportCourseWithoutReferences;
+
+  /**
+   * Type of a favorite
+   */
+  type: SCThingType.Favorite;
 }
 
 /**
diff --git a/src/core/things/Floor.ts b/src/core/things/Floor.ts
index a9f16c1c..45f00bd7 100644
--- a/src/core/things/Floor.ts
+++ b/src/core/things/Floor.ts
@@ -14,16 +14,11 @@
  */
 import {Feature, FeatureCollection, GeometryObject, LineString} from 'geojson';
 import {SCThingInPlace} from '../base/ThingInPlace';
-import {SCThing, SCThingMeta, SCThingTranslatableProperties} from '../Thing';
+import {SCThing, SCThingMeta, SCThingTranslatableProperties, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 import {SCPointOfInterestWithoutReferences} from './PointOfInterest';
 import {SCRoomWithoutReferences} from './Room';
 
-/**
- * Type of a floor
- */
-export type SCFloorType = 'floor';
-
 /**
  * A floor without references
  */
@@ -46,7 +41,7 @@ export interface SCFloorWithoutReferences extends SCThing {
   /**
    * Type of a floor
    */
-  type: SCFloorType;
+  type: SCThingType.Floor;
 }
 
 /**
@@ -61,7 +56,7 @@ export interface SCFloor extends SCFloorWithoutReferences, SCThingInPlace {
   /**
    * Type of a floor
    */
-  type: SCFloorType;
+  type: SCThingType.Floor;
 }
 
 /**
diff --git a/src/core/things/Message.ts b/src/core/things/Message.ts
index 0f646c37..5ac97d03 100644
--- a/src/core/things/Message.ts
+++ b/src/core/things/Message.ts
@@ -18,15 +18,10 @@ import {
   SCCreativeWorkWithoutReferences,
 } from '../base/CreativeWork';
 import {SCThingThatCanBeOfferedTranslatableProperties} from '../base/ThingThatCanBeOffered';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 import {SCISO8601Date} from '../types/Time';
 
-/**
- * Type of a message
- */
-export type SCMessageType = 'message';
-
 /**
  * A message without references
  */
@@ -54,7 +49,7 @@ export interface SCMessageWithoutReferences extends SCCreativeWorkWithoutReferen
   /**
    * Type of a message
    */
-  type: SCMessageType;
+  type: SCThingType.Message;
 }
 
 /**
@@ -69,7 +64,7 @@ export interface SCMessage extends SCCreativeWork, SCMessageWithoutReferences {
   /**
    * Type of a message
    */
-  type: SCMessageType;
+  type: SCThingType.Message;
 }
 
 /**
diff --git a/src/core/things/Organization.ts b/src/core/things/Organization.ts
index fd05de3d..5b6506b8 100644
--- a/src/core/things/Organization.ts
+++ b/src/core/things/Organization.ts
@@ -13,12 +13,7 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCThingInPlace} from '../base/ThingInPlace';
-import {SCThing, SCThingMeta} from '../Thing';
-
-/**
- * Type of an organization
- */
-export type SCOrganizationType = 'organization';
+import {SCThing, SCThingMeta, SCThingType} from '../Thing';
 
 /**
  * An organization without references
@@ -27,7 +22,7 @@ export interface SCOrganizationWithoutReferences extends SCThing {
   /**
    * Type of an organization
    */
-  type: SCOrganizationType;
+  type: SCThingType.Organization;
 }
 
 /**
@@ -37,7 +32,7 @@ export interface SCOrganization extends SCOrganizationWithoutReferences, SCThing
   /**
    * Type of an organization
    */
-  type: SCOrganizationType;
+  type: SCThingType.Organization;
 }
 
 /**
diff --git a/src/core/things/Person.ts b/src/core/things/Person.ts
index 9a98a59b..7fc214d3 100644
--- a/src/core/things/Person.ts
+++ b/src/core/things/Person.ts
@@ -12,7 +12,7 @@
  * You should have received a copy of the GNU General Public License along with
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
-import {SCThing, SCThingMeta} from '../Thing';
+import {SCThing, SCThingMeta, SCThingType} from '../Thing';
 import {SCNationality} from '../types/i18n';
 import {SCISO8601Date} from '../types/Time';
 import {SCBuildingWithoutReferences} from './Building';
@@ -20,11 +20,6 @@ import {SCOrganizationWithoutReferences} from './Organization';
 import {SCPointOfInterestWithoutReferences} from './PointOfInterest';
 import {SCRoomWithoutReferences} from './Room';
 
-/**
- * Type of a person
- */
-export type SCPersonType = 'person';
-
 /**
  * A person without references
  */
@@ -99,7 +94,7 @@ export interface SCPersonWithoutReferences extends SCThing {
   /**
    * Type of a person
    */
-  type: SCPersonType;
+  type: SCThingType.Person;
 }
 
 /**
@@ -118,6 +113,11 @@ export interface SCPerson extends SCPersonWithoutReferences {
     | SCPointOfInterestWithoutReferences
     | SCRoomWithoutReferences>;
 
+  /**
+   * Type of a person
+   */
+  type: SCThingType.Person;
+
   /**
    * Locations where the person performs her/his work
    */
diff --git a/src/core/things/PointOfInterest.ts b/src/core/things/PointOfInterest.ts
index 24c00d69..c26026c1 100644
--- a/src/core/things/PointOfInterest.ts
+++ b/src/core/things/PointOfInterest.ts
@@ -19,14 +19,9 @@ import {
   SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 
-/**
- * Type of a point of interest
- */
-export type SCPointOfInterestType = 'point of interest';
-
 /**
  * A point of interest without references
  */
@@ -42,7 +37,7 @@ export interface SCPointOfInterestWithoutReferences
   /**
    * Type of a point of interest
    */
-  type: SCPointOfInterestType;
+  type: SCThingType.PointOfInterest;
 }
 
 /**
@@ -57,7 +52,7 @@ export interface SCPointOfInterest extends SCPointOfInterestWithoutReferences, S
   /**
    * Type of a point of interest
    */
-  type: SCPointOfInterestType;
+  type: SCThingType.PointOfInterest;
 }
 
 /**
diff --git a/src/core/things/Room.ts b/src/core/things/Room.ts
index 6a1f6d3e..d17811d6 100644
--- a/src/core/things/Room.ts
+++ b/src/core/things/Room.ts
@@ -20,14 +20,9 @@ import {
   SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCTranslations} from '../types/i18n';
 
-/**
- * Type of a room
- */
-export type SCRoomType = 'room';
-
 /**
  * Categories of a room
  */
@@ -70,7 +65,7 @@ export interface SCRoomWithoutReferences
   /**
    * Type of the room
    */
-  type: SCRoomType;
+  type: SCThingType.Room;
 }
 
 /**
@@ -87,7 +82,7 @@ export interface SCRoom extends SCRoomWithoutReferences, SCThingInPlace {
   /**
    * Type of the room
    */
-  type: SCRoomType;
+  type: SCThingType.Room;
 }
 
 /**
diff --git a/src/core/things/Semester.ts b/src/core/things/Semester.ts
index 0e2857c3..24cbb02b 100644
--- a/src/core/things/Semester.ts
+++ b/src/core/things/Semester.ts
@@ -13,12 +13,7 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCAcademicTermWithoutReferences} from '../base/AcademicTerm';
-import {SCThingMeta} from '../Thing';
-
-/**
- * Type of a semester
- */
-export type SCSemesterType = 'semester';
+import {SCThingMeta, SCThingType} from '../Thing';
 
 /**
  * A semester without references
@@ -34,13 +29,17 @@ export interface SCSemesterWithoutReferences extends SCAcademicTermWithoutRefere
   /**
    * Type of the semester
    */
-  type: SCSemesterType;
+  type: SCThingType.Semester;
 }
 
 /**
  * A semester
  */
 export interface SCSemester extends SCSemesterWithoutReferences {
+  /**
+   * Type of the semester
+   */
+  type: SCThingType.Semester;
 }
 
 /**
diff --git a/src/core/things/Setting.ts b/src/core/things/Setting.ts
index 1364b21a..95d2e78f 100644
--- a/src/core/things/Setting.ts
+++ b/src/core/things/Setting.ts
@@ -16,10 +16,9 @@ import {
   SCThingWithCategoriesSpecificValues, SCThingWithCategoriesTranslatableProperties,
   SCThingWithCategoriesWithoutReferences,
 } from '../base/ThingWithCategories';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import { SCTranslations } from '../types/i18n';
 
-export type SCSettingType = 'setting';
 export type SCSettingCategories = string;
 
 /**
@@ -43,7 +42,7 @@ export interface SCSettingWithoutReferences
   /**
    * The type of this model
    */
-  type: SCSettingType;
+  type: SCThingType.Setting;
 }
 
 /**
@@ -59,6 +58,10 @@ export type SCSettingInputType = SCSettingSingleChoice
  * A setting with references
  */
 export interface SCSetting extends SCSettingWithoutReferences {
+  /**
+   * The type of this model
+   */
+  type: SCThingType.Setting;
 }
 
 /**
diff --git a/src/core/things/SportCourse.ts b/src/core/things/SportCourse.ts
index b32f0ca3..1be50c30 100644
--- a/src/core/things/SportCourse.ts
+++ b/src/core/things/SportCourse.ts
@@ -13,12 +13,7 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCEvent, SCEventWithoutReferences} from '../base/Event';
-import {SCThingMeta} from '../Thing';
-
-/**
- * Type of a sport course
- */
-export type SCSportCourseType = 'sport course';
+import {SCThingMeta, SCThingType} from '../Thing';
 
 /**
  * A sport course without references
@@ -27,7 +22,7 @@ export interface SCSportCourseWithoutReferences extends SCEventWithoutReferences
   /**
    * Type of a sport course
    */
-  type: SCSportCourseType;
+  type: SCThingType.SportCourse;
 }
 
 /**
@@ -37,7 +32,7 @@ export interface SCSportCourse extends SCEvent, SCSportCourseWithoutReferences {
   /**
    * Type of a sport course
    */
-  type: SCSportCourseType;
+  type: SCThingType.SportCourse;
 }
 
 /**
diff --git a/src/core/things/Ticket.ts b/src/core/things/Ticket.ts
index 27570175..519b018d 100644
--- a/src/core/things/Ticket.ts
+++ b/src/core/things/Ticket.ts
@@ -13,14 +13,9 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCThingInPlace} from '../base/ThingInPlace';
-import {SCThing, SCThingMeta} from '../Thing';
+import {SCThing, SCThingMeta, SCThingType} from '../Thing';
 import {SCISO8601Duration} from '../types/Time';
 
-/**
- * Type of a ticket
- */
-export type SCTicketType = 'ticket';
-
 /**
  * A ticket without references
  */
@@ -43,7 +38,7 @@ export interface SCTicketWithoutReferences extends SCThing {
   /**
    * Type of a ticket
    */
-  type: SCTicketType;
+  type: SCThingType.Ticket;
 }
 
 /**
@@ -53,7 +48,7 @@ export interface SCTicket extends SCTicketWithoutReferences, SCThingInPlace {
   /**
    * Type of a ticket
    */
-  type: SCTicketType;
+  type: SCThingType.Ticket;
 }
 
 /**
diff --git a/src/core/things/Tour.ts b/src/core/things/Tour.ts
index c222cb68..3d5ee2e3 100644
--- a/src/core/things/Tour.ts
+++ b/src/core/things/Tour.ts
@@ -12,12 +12,7 @@
  * You should have received a copy of the GNU General Public License along with
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
-import {SCThing, SCThingMeta} from '../Thing';
-
-/**
- * Type of a tour
- */
-export type SCTourType = 'tour';
+import {SCThing, SCThingMeta, SCThingType} from '../Thing';
 
 /**
  * A tour without references
@@ -36,13 +31,17 @@ export interface SCTourWithoutReferences extends SCThing {
   /**
    * Type of a tour
    */
-  type: SCTourType;
+  type: SCThingType.Tour;
 }
 
 /**
  * A tour
  */
 export interface SCTour extends SCTourWithoutReferences {
+  /**
+   * Type of a tour
+   */
+  type: SCThingType.Tour;
 }
 
 /**
diff --git a/src/core/things/Video.ts b/src/core/things/Video.ts
index f570f9c3..c7cf72a1 100644
--- a/src/core/things/Video.ts
+++ b/src/core/things/Video.ts
@@ -13,16 +13,11 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 import {SCCreativeWork, SCCreativeWorkWithoutReferences} from '../base/CreativeWork';
-import {SCThingMeta} from '../Thing';
+import {SCThingMeta, SCThingType} from '../Thing';
 import {SCLanguage} from '../types/i18n';
 import {SCISO8601Duration} from '../types/Time';
 import {SCPersonWithoutReferences} from './Person';
 
-/**
- * Type of a video
- */
-export type SCVideoType = 'video';
-
 /**
  * A video without references
  */
@@ -55,7 +50,7 @@ export interface SCVideoWithoutReferences extends SCCreativeWorkWithoutReference
   /**
    * Type of an Video
    */
-  type: SCVideoType;
+  type: SCThingType.Video;
 }
 
 export interface SCVideoSource {
@@ -114,7 +109,7 @@ export interface SCVideo extends SCCreativeWork, SCVideoWithoutReferences {
   /**
    * Type of a video
    */
-  type: SCVideoType;
+  type: SCThingType.Video;
 }
 
 export class SCVideoMeta extends SCThingMeta {
diff --git a/src/core/types/config/Backend.ts b/src/core/types/config/Backend.ts
index c30f2cf8..67d47f8c 100644
--- a/src/core/types/config/Backend.ts
+++ b/src/core/types/config/Backend.ts
@@ -12,7 +12,6 @@
  * You should have received a copy of the GNU General Public License along with
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
-import {SCThingTypes} from '../../Thing';
 import {SCSearchSortType} from '../sorts/Abstract';
 import {SCUuid} from '../UUID';
 import {SCMonitoringConfiguration} from './Monitoring';
@@ -25,8 +24,10 @@ export interface SCBackendConfiguration {
    * A list of hidden SC types
    *
    * If a type is hidden it won't show in any result unless the type is filtered for
+   * 
+   * Strings must be elements of the SCThingType enumeration.
    */
-  hiddenTypes: SCThingTypes[];
+  hiddenTypes: string[];
 
   /**
    * Name of university
@@ -63,7 +64,7 @@ export interface SCBackendConfigurationSortableField {
    *
    * If no type is given it is assumed it exists on every type
    */
-  onlyOnTypes?: SCThingTypes[];
+  onlyOnTypes?: string[];
 
   /**
    * A list of supported sorts on this field
@@ -110,7 +111,7 @@ export interface SCBackendConfigurationSearchBoosting {
   /**
    * Type of things the factor should be applied to
    */
-  type: SCThingTypes;
+  type: string;
 }
 
 /**
@@ -127,7 +128,7 @@ export interface SCBackendAggregationConfiguration {
    *
    * If the type is not given is is assumed the field exists on every type
    */
-  onlyOnTypes?: SCThingTypes[];
+  onlyOnTypes?: string[];
 }
 
 /**