diff --git a/backend/package-lock.json b/backend/package-lock.json
index b998613b5..a174865aa 100644
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -5697,6 +5697,11 @@
       "integrity": "sha512-NuaNSa6flKT5JaSYQzJok04JzTL1CA6aGhv5rfLW3PgqA+M2ChpZQnAC8h8i4ZFkBS8X5RqkDBHA7r4hej3K9A==",
       "dev": true
     },
+    "random-bigint": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/random-bigint/-/random-bigint-0.0.1.tgz",
+      "integrity": "sha512-X+NTsf5Hzl/tRNLiNTD3N1LRU0eKdIE0+plNlV1CmXLTlnAxj6HipcTnOhWvFRoSytCz6l1f4KYFf/iH8NNSLw=="
+    },
     "range-parser": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/range-parser/-/range-parser-1.2.1.tgz",
diff --git a/backend/package.json b/backend/package.json
index ee7365b72..9da51cb7f 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -28,6 +28,7 @@
     "jsonwebtoken": "^8.5.1",
     "module-alias": "^2.2.2",
     "mysql2": "^2.3.0",
+    "random-bigint": "^0.0.1",
     "reflect-metadata": "^0.1.13",
     "sodium-native": "^3.3.0",
     "ts-jest": "^27.0.5",
diff --git a/backend/src/graphql/resolver/UserResolver.ts b/backend/src/graphql/resolver/UserResolver.ts
index fc57e793d..6c140bc62 100644
--- a/backend/src/graphql/resolver/UserResolver.ts
+++ b/backend/src/graphql/resolver/UserResolver.ts
@@ -29,6 +29,7 @@ import { LoginUserRepository } from '../../typeorm/repository/LoginUser'
 import { LoginUserBackupRepository } from '../../typeorm/repository/LoginUserBackup'
 import { LoginUser } from '@entity/LoginUser'
 import { LoginUserBackup } from '@entity/LoginUserBackup'
+import { LoginEmailOptIn } from '@entity/LoginEmailOptIn'
 
 // TODO apparently the types are cannot be loaded correctly? IDK whats wrong and we have to use require
 // import {
@@ -43,6 +44,8 @@ import { LoginUserBackup } from '@entity/LoginUserBackup'
 // } from 'sodium-native'
 // eslint-disable-next-line @typescript-eslint/no-var-requires
 const sodium = require('sodium-native')
+// eslint-disable-next-line @typescript-eslint/no-var-requires
+const random = require('random-bigint')
 
 // We will reuse this for changePassword
 const isPassword = (password: string): boolean => {
@@ -374,16 +377,23 @@ export class UserResolver {
         throw new Error('error saving user')
       })
 
-      // TODO: send EMail (EMAIL_OPT_IN_REGISTER)
-      // const emailType = 2
-      // auto emailOptIn = controller::EmailVerificationCode::create(userModel->getID(), model::table::EMAIL_OPT_IN_REGISTER);
-      //     auto code = createEmailVerificationCode();
-      //     auto db = new model::table::EmailOptIn(code, userModel->getID(), model::table::EMAIL_OPT_IN_REGISTER);
-      // auto emailOptInModel = emailOptIn->getModel();
-      // if (!emailOptInModel->insertIntoDB(false)) {
-      //	emailOptInModel->sendErrorsAsEmail();
-      //	return stateError("insert emailOptIn failed");
-      // }
+      // Store EmailOptIn in DB
+      const emailOptIn = new LoginEmailOptIn()
+      emailOptIn.userId = loginUserId
+      emailOptIn.verificationCode = random(64) // TODO generate verificationCode
+      emailOptIn.emailOptInTypeId = 2
+
+      await queryRunner.manager.save(emailOptIn).catch((error) => {
+        // TODO: Send error email instead of throw error
+        // if (!emailOptInModel->insertIntoDB(false)) {
+        //	emailOptInModel->sendErrorsAsEmail();
+        //	return stateError("insert emailOptIn failed");
+        // }
+        // eslint-disable-next-line no-console
+        console.log('Error while saving emailOptIn', error)
+        throw new Error('error saving email opt in')
+      })
+      // TODO: Send EmailOptIn to user.email
       // emailOptIn->setBaseUrl(user->getGroupBaseUrl() + ServerConfig::g_frontend_checkEmailPath);
       // em->addEmail(new model::Email(emailOptIn, user, model::Email::convertTypeFromInt(emailType)));
       await queryRunner.commitTransaction()
diff --git a/backend/yarn.lock b/backend/yarn.lock
index 7cd146647..75b998c17 100644
--- a/backend/yarn.lock
+++ b/backend/yarn.lock
@@ -4615,6 +4615,11 @@ queue-microtask@^1.2.2:
   resolved "https://registry.npmjs.org/queue-microtask/-/queue-microtask-1.2.3.tgz"
   integrity sha512-NuaNSa6flKT5JaSYQzJok04JzTL1CA6aGhv5rfLW3PgqA+M2ChpZQnAC8h8i4ZFkBS8X5RqkDBHA7r4hej3K9A==
 
+random-bigint@^0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/random-bigint/-/random-bigint-0.0.1.tgz#684de0a93784ab7448a441393916f0e632c95df9"
+  integrity sha512-X+NTsf5Hzl/tRNLiNTD3N1LRU0eKdIE0+plNlV1CmXLTlnAxj6HipcTnOhWvFRoSytCz6l1f4KYFf/iH8NNSLw==
+
 range-parser@~1.2.1:
   version "1.2.1"
   resolved "https://registry.npmjs.org/range-parser/-/range-parser-1.2.1.tgz"