diff --git a/app/repository/groups-repository.js b/app/repository/groups-repository.js
new file mode 100644
index 00000000..616fa592
--- /dev/null
+++ b/app/repository/groups-repository.js
@@ -0,0 +1,14 @@
+'use strict';
+
+const BaseRepository = require('./_base.repository');
+const Group = require('../models/group-model');
+
+class GroupsRepository extends BaseRepository {
+
+    constructor() {
+        super(Group);
+
+    }
+}
+
+module.exports = new GroupsRepository();
\ No newline at end of file
diff --git a/app/services/tactics-service.js b/app/services/tactics-service.js
index 5fd406bf..d2176a35 100644
--- a/app/services/tactics-service.js
+++ b/app/services/tactics-service.js
@@ -11,14 +11,7 @@ const config = require('../config/config');
 const regexValidator = require('../lib/regex');
 const {lastUpdatedByQueryHelper} = require('../lib/request-parameter-helper');
 
-const errors = {
-    missingParameter: 'Missing required parameter',
-    badlyFormattedParameter: 'Badly formatted parameter',
-    duplicateId: 'Duplicate id',
-    notFound: 'Document not found',
-    invalidQueryStringParameter: 'Invalid query string parameter'
-};
-exports.errors = errors;
+const { BadlyFormattedParameterError, DuplicateIdError, NotFoundError, InvalidQueryStringParameterError, MissingParameterError } = require('../exceptions');
 
 const BaseService = require('./_base.service');
 const TacticsRepository = require('../repository/tactics-repository');