diff --git a/CHANGELOG.md b/CHANGELOG.md
index d52ba760c..3e04d4c21 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,8 +4,49 @@ All notable changes to this project will be documented in this file. Dates are d
 
 Generated by [`auto-changelog`](https://github.com/CookPete/auto-changelog).
 
+#### [1.21.0](https://github.com/gradido/gradido/compare/1.20.0...1.21.0)
+
+- feat(frontend): preserve email after login [`#2994`](https://github.com/gradido/gradido/pull/2994)
+- feat(frontend): send coins via identifier [`#2989`](https://github.com/gradido/gradido/pull/2989)
+- feat(backend): export user events to klicktipp [`#2916`](https://github.com/gradido/gradido/pull/2916)
+- fix(backend): add extension pug json and css to nodemon. [`#2996`](https://github.com/gradido/gradido/pull/2996)
+- feat(backend): send coins via alias [`#2988`](https://github.com/gradido/gradido/pull/2988)
+- refactor(backend): replace jasonwebtoken with jose [`#2975`](https://github.com/gradido/gradido/pull/2975)
+- feat(frontend): username in wallet [`#2984`](https://github.com/gradido/gradido/pull/2984)
+- feat(frontend): add community to send form [`#2986`](https://github.com/gradido/gradido/pull/2986)
+- fix(frontend): date fns locales [`#2983`](https://github.com/gradido/gradido/pull/2983)
+- refactor(federation): federation reduce spam [`#2967`](https://github.com/gradido/gradido/pull/2967)
+- refactor(federation): refactor federation clients [`#2965`](https://github.com/gradido/gradido/pull/2965)
+- feat(backend): migrate transactions table for x community sendcoins [`#2917`](https://github.com/gradido/gradido/pull/2917)
+- feat(backend): alias in update user info [`#2727`](https://github.com/gradido/gradido/pull/2727)
+- refactor(backend): eslint comments [`#2981`](https://github.com/gradido/gradido/pull/2981)
+- refactor(backend): eslint security [`#2980`](https://github.com/gradido/gradido/pull/2980)
+- refactor(backend): rename klicktippSignIn to subscribe. [`#2973`](https://github.com/gradido/gradido/pull/2973)
+- refactor(backend): eslint typescript strict [`#2979`](https://github.com/gradido/gradido/pull/2979)
+- fix(frontend): between store problems [`#2972`](https://github.com/gradido/gradido/pull/2972)
+- refactor(other): delete build folders [`#2977`](https://github.com/gradido/gradido/pull/2977)
+- refactor(backend): no email in user [`#2953`](https://github.com/gradido/gradido/pull/2953)
+- refactor(frontend): remove email in wallet [`#2952`](https://github.com/gradido/gradido/pull/2952)
+- fix(frontend): update jest-canvas-mock version to resolve window mock problem in tests [`#2974`](https://github.com/gradido/gradido/pull/2974)
+- feat(federation): federation autoreload on codechange [`#2969`](https://github.com/gradido/gradido/pull/2969)
+- feat(backend): add fields to subscriber [`#2887`](https://github.com/gradido/gradido/pull/2887)
+- feat(backend): x-com-2: distingue communities and communities_federation in database [`#2890`](https://github.com/gradido/gradido/pull/2890)
+- feat(backend): add event for subscribe and unsubscribe [`#2886`](https://github.com/gradido/gradido/pull/2886)
+- refactor(backend): eslint disable more typesafety [`#2922`](https://github.com/gradido/gradido/pull/2922)
+- refactor(backend): eslint disable tests typesafer [`#2921`](https://github.com/gradido/gradido/pull/2921)
+- refactor(backend): eslint disable @typescript eslint/unbound method [`#2920`](https://github.com/gradido/gradido/pull/2920)
+- docs(other): removed obsolete yarn cron docu [`#2909`](https://github.com/gradido/gradido/pull/2909)
+- refactor(other): finalize workflow separation and resolve mariadb and database dependencies in workflow files [`#2962`](https://github.com/gradido/gradido/pull/2962)
+- refactor(workflow): align workflow naming and remove docker-compose filter from build tests [`#2894`](https://github.com/gradido/gradido/pull/2894)
+- refactor(backend): eslint plugin promise + fixes [`#2830`](https://github.com/gradido/gradido/pull/2830)
+- fix(backend): log stack trace included [`#2915`](https://github.com/gradido/gradido/pull/2915)
+- refactor(backend): prettier refine config [`#2832`](https://github.com/gradido/gradido/pull/2832)
+
 #### [1.20.0](https://github.com/gradido/gradido/compare/1.19.1...1.20.0)
 
+> 12 April 2023
+
+- chore(release): v1.20.0 [`#2939`](https://github.com/gradido/gradido/pull/2939)
 - fix(backend): no await for emails [`#2918`](https://github.com/gradido/gradido/pull/2918)
 - fix(frontend): no receiver on send by link [`#2933`](https://github.com/gradido/gradido/pull/2933)
 - fix(admin): pagination set currentPage by switch tabs [`#2902`](https://github.com/gradido/gradido/pull/2902)
diff --git a/admin/.eslintignore b/admin/.eslintignore
index 94934f9e7..e19e2338d 100644
--- a/admin/.eslintignore
+++ b/admin/.eslintignore
@@ -1,3 +1,3 @@
 node_modules/
-dist/
+build/
 coverage/
\ No newline at end of file
diff --git a/admin/.gitignore b/admin/.gitignore
index a67d270bc..3bc7bb4b2 100644
--- a/admin/.gitignore
+++ b/admin/.gitignore
@@ -1,5 +1,5 @@
 node_modules/
-dist/
+build/
 .cache/
 
 /.env
diff --git a/admin/Dockerfile b/admin/Dockerfile
index ed0623a63..029339f10 100644
--- a/admin/Dockerfile
+++ b/admin/Dockerfile
@@ -84,7 +84,7 @@ CMD /bin/sh -c "yarn run dev"
 FROM base as production
 
 # Copy "binary"-files from build image
-COPY --from=build ${DOCKER_WORKDIR}/dist ./dist
+COPY --from=build ${DOCKER_WORKDIR}/build ./build
 # We also copy the node_modules express and serve-static for the run script
 COPY --from=build ${DOCKER_WORKDIR}/node_modules ./node_modules
 # Copy static files
diff --git a/admin/package.json b/admin/package.json
index 04c9a60e8..823201b7d 100644
--- a/admin/package.json
+++ b/admin/package.json
@@ -3,7 +3,7 @@
   "description": "Administraion Interface for Gradido",
   "main": "index.js",
   "author": "Moriz Wahl",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "license": "Apache-2.0",
   "private": false,
   "scripts": {
@@ -11,7 +11,7 @@
     "serve": "vue-cli-service serve --open",
     "build": "vue-cli-service build",
     "dev": "yarn run serve",
-    "analyse-bundle": "yarn build && webpack-bundle-analyzer dist/webpack.stats.json",
+    "analyse-bundle": "yarn build && webpack-bundle-analyzer build/webpack.stats.json",
     "lint": "eslint --max-warnings=0 --ext .js,.vue,.json .",
     "stylelint": "stylelint --max-warnings=0 '**/*.{scss,vue}'",
     "test": "cross-env TZ=UTC jest",
diff --git a/admin/run/server.js b/admin/run/server.js
index bccefc65c..b5078a0cf 100644
--- a/admin/run/server.js
+++ b/admin/run/server.js
@@ -9,10 +9,10 @@ const port = process.env.PORT || 8080
 // Express Server
 const app = express()
 // Serve files
-app.use(express.static(path.join(__dirname, '../dist')))
+app.use(express.static(path.join(__dirname, '../build')))
 // Default to index.html
 app.get('*', (req, res) => {
-  res.sendFile(path.join(__dirname, '../dist/index.html'))
+  res.sendFile(path.join(__dirname, '../build/index.html'))
 })
 
 app.listen(port, hostname, () => {
diff --git a/admin/src/components/Fedaration/FederationVisualizeItem.vue b/admin/src/components/Fedaration/FederationVisualizeItem.vue
index faace7da1..a947387f4 100644
--- a/admin/src/components/Fedaration/FederationVisualizeItem.vue
+++ b/admin/src/components/Fedaration/FederationVisualizeItem.vue
@@ -13,7 +13,7 @@
 </template>
 <script>
 import { formatDistanceToNow } from 'date-fns'
-import { de, en, fr, es, nl } from 'date-fns/locale'
+import { de, enUS as en, fr, es, nl } from 'date-fns/locale'
 
 const locales = { en, de, es, fr, nl }
 
diff --git a/admin/src/store/store.js b/admin/src/store/store.js
index 7d43c8ce8..0263cf33f 100644
--- a/admin/src/store/store.js
+++ b/admin/src/store/store.js
@@ -37,6 +37,7 @@ export const actions = {
 const store = new Vuex.Store({
   plugins: [
     createPersistedState({
+      key: 'gradido-admin',
       storage: window.localStorage,
     }),
   ],
diff --git a/admin/vue.config.js b/admin/vue.config.js
index 8cc1e4b89..a92b26419 100644
--- a/admin/vue.config.js
+++ b/admin/vue.config.js
@@ -49,5 +49,5 @@ module.exports = {
     // Enable CSS source maps.
     sourceMap: CONFIG.NODE_ENV !== 'production',
   },
-  outputDir: path.resolve(__dirname, './dist'),
+  outputDir: path.resolve(__dirname, './build'),
 }
diff --git a/backend/.eslintignore b/backend/.eslintignore
index f6b255e92..1ae86fe5e 100644
--- a/backend/.eslintignore
+++ b/backend/.eslintignore
@@ -1,3 +1,4 @@
 node_modules
 **/*.min.js
-build
\ No newline at end of file
+build
+coverage
\ No newline at end of file
diff --git a/backend/.eslintrc.js b/backend/.eslintrc.js
index d00b9199a..78ac9e41e 100644
--- a/backend/.eslintrc.js
+++ b/backend/.eslintrc.js
@@ -12,6 +12,8 @@ module.exports = {
     'plugin:prettier/recommended',
     'plugin:import/recommended',
     'plugin:import/typescript',
+    'plugin:security/recommended',
+    'plugin:@eslint-community/eslint-comments/recommended',
   ],
   settings: {
     'import/parsers': {
@@ -25,7 +27,8 @@ module.exports = {
     },
   },
   rules: {
-    'no-console': ['error'],
+    'no-console': 'error',
+    camelcase: ['error', { allow: ['FederationClient_*'] }],
     'no-debugger': 'error',
     'prettier/prettier': [
       'error',
@@ -151,6 +154,11 @@ module.exports = {
     'promise/valid-params': 'warn',
     'promise/prefer-await-to-callbacks': 'error',
     'promise/no-multiple-resolved': 'error',
+    // eslint comments
+    '@eslint-community/eslint-comments/disable-enable-pair': ['error', { allowWholeFile: true }],
+    '@eslint-community/eslint-comments/no-restricted-disable': 'error',
+    '@eslint-community/eslint-comments/no-use': 'off',
+    '@eslint-community/eslint-comments/require-description': 'off',
   },
   overrides: [
     // only for ts files
@@ -159,6 +167,7 @@ module.exports = {
       extends: [
         'plugin:@typescript-eslint/recommended',
         'plugin:@typescript-eslint/recommended-requiring-type-checking',
+        'plugin:@typescript-eslint/strict',
         'plugin:type-graphql/recommended',
       ],
       rules: {
@@ -169,11 +178,14 @@ module.exports = {
         '@typescript-eslint/prefer-regexp-exec': 'off',
         // this should not run on ts files: https://github.com/import-js/eslint-plugin-import/issues/2215#issuecomment-911245486
         'import/unambiguous': 'off',
+        // this is not compatible with typeorm, due to joined tables can be null, but are not defined as nullable
+        '@typescript-eslint/no-unnecessary-condition': 'off',
       },
       parserOptions: {
         tsconfigRootDir: __dirname,
         project: ['./tsconfig.json', '**/tsconfig.json'],
         // this is to properly reference the referenced project database without requirement of compiling it
+        // eslint-disable-next-line camelcase
         EXPERIMENTAL_useSourceOfProjectReferenceRedirect: true,
       },
     },
diff --git a/backend/jest.config.js b/backend/jest.config.js
index ca12668fa..81ebbec55 100644
--- a/backend/jest.config.js
+++ b/backend/jest.config.js
@@ -7,7 +7,7 @@ module.exports = {
   collectCoverageFrom: ['src/**/*.ts', '!**/node_modules/**', '!src/seeds/**', '!build/**'],
   coverageThreshold: {
     global: {
-      lines: 85,
+      lines: 89,
     },
   },
   setupFiles: ['<rootDir>/test/testSetup.ts'],
diff --git a/backend/package.json b/backend/package.json
index c5e0df3c5..68ec89ec0 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gradido-backend",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "description": "Gradido unified backend providing an API-Service for Gradido Transactions",
   "main": "src/index.ts",
   "repository": "https://github.com/gradido/gradido/backend",
@@ -11,11 +11,11 @@
     "build": "tsc --build && mkdir -p build/src/emails/templates/ && cp -r src/emails/templates/* build/src/emails/templates/ && mkdir -p build/src/locales/ && cp -r src/locales/*.json build/src/locales/",
     "clean": "tsc --build --clean",
     "start": "cross-env TZ=UTC TS_NODE_BASEURL=./build node -r tsconfig-paths/register build/src/index.js",
-    "dev": "cross-env TZ=UTC nodemon -w src --ext ts --exec ts-node -r tsconfig-paths/register src/index.ts",
+    "dev": "cross-env TZ=UTC nodemon -w src --ext ts,pug,json,css --exec ts-node -r tsconfig-paths/register src/index.ts",
     "lint": "eslint --max-warnings=0 .",
     "test": "cross-env TZ=UTC NODE_ENV=development jest --runInBand --forceExit --detectOpenHandles",
     "seed": "cross-env TZ=UTC NODE_ENV=development ts-node -r tsconfig-paths/register src/seeds/index.ts",
-    "klicktipp": "cross-env TZ=UTC NODE_ENV=development ts-node -r tsconfig-paths/register src/util/klicktipp.ts",
+    "klicktipp": "cross-env TZ=UTC NODE_ENV=development ts-node -r tsconfig-paths/register src/util/executeKlicktipp.ts",
     "locales": "scripts/sort.sh"
   },
   "dependencies": {
@@ -33,7 +33,7 @@
     "graphql": "^15.5.1",
     "graphql-request": "5.0.0",
     "i18n": "^0.15.1",
-    "jsonwebtoken": "^8.5.1",
+    "jose": "^4.14.4",
     "lodash.clonedeep": "^4.5.0",
     "log4js": "^6.4.6",
     "mysql2": "^2.3.0",
@@ -46,12 +46,12 @@
     "uuid": "^8.3.2"
   },
   "devDependencies": {
+    "@eslint-community/eslint-plugin-eslint-comments": "^3.2.1",
     "@types/email-templates": "^10.0.1",
     "@types/express": "^4.17.12",
     "@types/faker": "^5.5.9",
     "@types/i18n": "^0.13.4",
     "@types/jest": "^27.0.2",
-    "@types/jsonwebtoken": "^8.5.2",
     "@types/lodash.clonedeep": "^4.5.6",
     "@types/node": "^16.10.3",
     "@types/nodemailer": "^6.4.4",
@@ -68,6 +68,7 @@
     "eslint-plugin-n": "^15.7.0",
     "eslint-plugin-prettier": "^4.2.1",
     "eslint-plugin-promise": "^6.1.1",
+    "eslint-plugin-security": "^1.7.1",
     "eslint-plugin-type-graphql": "^1.0.0",
     "faker": "^5.5.3",
     "graphql-tag": "^2.12.6",
diff --git a/backend/src/apis/HttpRequest.ts b/backend/src/apis/HttpRequest.ts
index f40d577bd..27578463a 100644
--- a/backend/src/apis/HttpRequest.ts
+++ b/backend/src/apis/HttpRequest.ts
@@ -7,7 +7,6 @@ import axios from 'axios'
 import { LogError } from '@/server/LogError'
 import { backendLogger as logger } from '@/server/logger'
 
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
 export const apiPost = async (url: string, payload: unknown): Promise<any> => {
   logger.trace('POST', url, payload)
   try {
@@ -25,7 +24,6 @@ export const apiPost = async (url: string, payload: unknown): Promise<any> => {
   }
 }
 
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
 export const apiGet = async (url: string): Promise<any> => {
   logger.trace('GET: url=' + url)
   try {
diff --git a/backend/src/apis/KlicktippController.ts b/backend/src/apis/KlicktippController.ts
index a4b5b6be7..ea6a8e47c 100644
--- a/backend/src/apis/KlicktippController.ts
+++ b/backend/src/apis/KlicktippController.ts
@@ -4,15 +4,15 @@
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
 /* eslint-disable @typescript-eslint/no-explicit-any */
 /* eslint-disable @typescript-eslint/explicit-module-boundary-types */
-
 import { CONFIG } from '@/config'
+import { backendLogger as logger } from '@/server/logger'
 
 // eslint-disable-next-line import/no-relative-parent-imports
 import KlicktippConnector from 'klicktipp-api'
 
 const klicktippConnector = new KlicktippConnector()
 
-export const klicktippSignIn = async (
+export const subscribe = async (
   email: string,
   language: string,
   firstName?: string,
@@ -28,13 +28,6 @@ export const klicktippSignIn = async (
   return result
 }
 
-export const signout = async (email: string, language: string): Promise<boolean> => {
-  if (!CONFIG.KLICKTIPP) return true
-  const apiKey = language === 'de' ? CONFIG.KLICKTIPP_APIKEY_DE : CONFIG.KLICKTIPP_APIKEY_EN
-  const result = await klicktippConnector.signoff(apiKey, email)
-  return result
-}
-
 export const unsubscribe = async (email: string): Promise<boolean> => {
   if (!CONFIG.KLICKTIPP) return true
   const isLogin = await loginKlicktippUser()
@@ -48,9 +41,12 @@ export const getKlickTippUser = async (email: string): Promise<any> => {
   if (!CONFIG.KLICKTIPP) return true
   const isLogin = await loginKlicktippUser()
   if (isLogin) {
-    const subscriberId = await klicktippConnector.subscriberSearch(email)
-    const result = await klicktippConnector.subscriberGet(subscriberId)
-    return result
+    try {
+      return klicktippConnector.subscriberGet(await klicktippConnector.subscriberSearch(email))
+    } catch (e) {
+      logger.error('Could not find subscriber', email)
+      return false
+    }
   }
   return false
 }
@@ -60,38 +56,6 @@ export const loginKlicktippUser = async (): Promise<boolean> => {
   return await klicktippConnector.login(CONFIG.KLICKTIPP_USER, CONFIG.KLICKTIPP_PASSWORD)
 }
 
-export const logoutKlicktippUser = async (): Promise<boolean> => {
-  if (!CONFIG.KLICKTIPP) return true
-  return await klicktippConnector.logout()
-}
-
-export const untagUser = async (email: string, tagId: string): Promise<boolean> => {
-  if (!CONFIG.KLICKTIPP) return true
-  const isLogin = await loginKlicktippUser()
-  if (isLogin) {
-    return await klicktippConnector.untag(email, tagId)
-  }
-  return false
-}
-
-export const tagUser = async (email: string, tagIds: string): Promise<boolean> => {
-  if (!CONFIG.KLICKTIPP) return true
-  const isLogin = await loginKlicktippUser()
-  if (isLogin) {
-    return await klicktippConnector.tag(email, tagIds)
-  }
-  return false
-}
-
-export const getKlicktippTagMap = async () => {
-  if (!CONFIG.KLICKTIPP) return true
-  const isLogin = await loginKlicktippUser()
-  if (isLogin) {
-    return await klicktippConnector.tagIndex()
-  }
-  return ''
-}
-
 export const addFieldsToSubscriber = async (
   email: string,
   fields: any = {},
@@ -101,8 +65,18 @@ export const addFieldsToSubscriber = async (
   if (!CONFIG.KLICKTIPP) return true
   const isLogin = await loginKlicktippUser()
   if (isLogin) {
-    const subscriberId = await klicktippConnector.subscriberSearch(email)
-    return klicktippConnector.subscriberUpdate(subscriberId, fields, newemail, newsmsnumber)
+    try {
+      logger.info('Updating of subscriber', email)
+      return klicktippConnector.subscriberUpdate(
+        await klicktippConnector.subscriberSearch(email),
+        fields,
+        newemail,
+        newsmsnumber,
+      )
+    } catch (e) {
+      logger.error('Could not update subscriber', email, fields, e)
+      return false
+    }
   }
   return false
 }
diff --git a/backend/src/auth/CustomJwtPayload.ts b/backend/src/auth/CustomJwtPayload.ts
index 7966b413e..e20e5b272 100644
--- a/backend/src/auth/CustomJwtPayload.ts
+++ b/backend/src/auth/CustomJwtPayload.ts
@@ -1,5 +1,5 @@
-import { JwtPayload } from 'jsonwebtoken'
+import { JWTPayload } from 'jose'
 
-export interface CustomJwtPayload extends JwtPayload {
+export interface CustomJwtPayload extends JWTPayload {
   gradidoID: string
 }
diff --git a/backend/src/auth/INALIENABLE_RIGHTS.ts b/backend/src/auth/INALIENABLE_RIGHTS.ts
index adca3640f..25a4fa76d 100644
--- a/backend/src/auth/INALIENABLE_RIGHTS.ts
+++ b/backend/src/auth/INALIENABLE_RIGHTS.ts
@@ -8,4 +8,5 @@ export const INALIENABLE_RIGHTS = [
   RIGHTS.SET_PASSWORD,
   RIGHTS.QUERY_TRANSACTION_LINK,
   RIGHTS.QUERY_OPT_IN,
+  RIGHTS.CHECK_USERNAME,
 ]
diff --git a/backend/src/auth/JWT.ts b/backend/src/auth/JWT.ts
index 75a69cd0c..d8c6c81cf 100644
--- a/backend/src/auth/JWT.ts
+++ b/backend/src/auth/JWT.ts
@@ -1,22 +1,33 @@
-import { verify, sign } from 'jsonwebtoken'
+import { SignJWT, jwtVerify } from 'jose'
 
 import { CONFIG } from '@/config/'
 import { LogError } from '@/server/LogError'
 
 import { CustomJwtPayload } from './CustomJwtPayload'
 
-export const decode = (token: string): CustomJwtPayload | null => {
+export const decode = async (token: string): Promise<CustomJwtPayload | null> => {
   if (!token) throw new LogError('401 Unauthorized')
+
   try {
-    return <CustomJwtPayload>verify(token, CONFIG.JWT_SECRET)
+    const secret = new TextEncoder().encode(CONFIG.JWT_SECRET)
+    const { payload } = await jwtVerify(token, secret, {
+      issuer: 'urn:gradido:issuer',
+      audience: 'urn:gradido:audience',
+    })
+    return payload as CustomJwtPayload
   } catch (err) {
     return null
   }
 }
 
-export const encode = (gradidoID: string): string => {
-  const token = sign({ gradidoID }, CONFIG.JWT_SECRET, {
-    expiresIn: CONFIG.JWT_EXPIRES_IN,
-  })
+export const encode = async (gradidoID: string): Promise<string> => {
+  const secret = new TextEncoder().encode(CONFIG.JWT_SECRET)
+  const token = await new SignJWT({ gradidoID, 'urn:gradido:claim': true })
+    .setProtectedHeader({ alg: 'HS256' })
+    .setIssuedAt()
+    .setIssuer('urn:gradido:issuer')
+    .setAudience('urn:gradido:audience')
+    .setExpirationTime(CONFIG.JWT_EXPIRES_IN)
+    .sign(secret)
   return token
 }
diff --git a/backend/src/auth/RIGHTS.ts b/backend/src/auth/RIGHTS.ts
index df4eed8a1..b3627ff7a 100644
--- a/backend/src/auth/RIGHTS.ts
+++ b/backend/src/auth/RIGHTS.ts
@@ -34,6 +34,7 @@ export enum RIGHTS {
   LIST_ALL_CONTRIBUTION_MESSAGES = 'LIST_ALL_CONTRIBUTION_MESSAGES',
   OPEN_CREATIONS = 'OPEN_CREATIONS',
   USER = 'USER',
+  CHECK_USERNAME = 'CHECK_USERNAME',
   // Admin
   SEARCH_USERS = 'SEARCH_USERS',
   SET_USER_ROLE = 'SET_USER_ROLE',
diff --git a/backend/src/config/index.ts b/backend/src/config/index.ts
index fc88011ea..8d1ed8ae6 100644
--- a/backend/src/config/index.ts
+++ b/backend/src/config/index.ts
@@ -12,11 +12,11 @@ Decimal.set({
 })
 
 const constants = {
-  DB_VERSION: '0065-refactor_communities_table',
+  DB_VERSION: '0066-x-community-sendcoins-transactions_table',
   DECAY_START_TIME: new Date('2021-05-13 17:46:31-0000'), // GMT+0
   LOG4JS_CONFIG: 'log4js-config.json',
   // default log level on production should be info
-  LOG_LEVEL: process.env.LOG_LEVEL || 'info',
+  LOG_LEVEL: process.env.LOG_LEVEL ?? 'info',
   CONFIG_VERSION: {
     DEFAULT: 'DEFAULT',
     EXPECTED: 'v15.2023-02-07',
@@ -25,67 +25,67 @@ const constants = {
 }
 
 const server = {
-  PORT: process.env.PORT || 4000,
-  JWT_SECRET: process.env.JWT_SECRET || 'secret123',
-  JWT_EXPIRES_IN: process.env.JWT_EXPIRES_IN || '10m',
+  PORT: process.env.PORT ?? 4000,
+  JWT_SECRET: process.env.JWT_SECRET ?? 'secret123',
+  JWT_EXPIRES_IN: process.env.JWT_EXPIRES_IN ?? '10m',
   GRAPHIQL: process.env.GRAPHIQL === 'true' || false,
-  GDT_API_URL: process.env.GDT_API_URL || 'https://gdt.gradido.net',
+  GDT_API_URL: process.env.GDT_API_URL ?? 'https://gdt.gradido.net',
   PRODUCTION: process.env.NODE_ENV === 'production' || false,
 }
 
 const database = {
-  DB_HOST: process.env.DB_HOST || 'localhost',
+  DB_HOST: process.env.DB_HOST ?? 'localhost',
   DB_PORT: process.env.DB_PORT ? parseInt(process.env.DB_PORT) : 3306,
-  DB_USER: process.env.DB_USER || 'root',
-  DB_PASSWORD: process.env.DB_PASSWORD || '',
-  DB_DATABASE: process.env.DB_DATABASE || 'gradido_community',
-  TYPEORM_LOGGING_RELATIVE_PATH: process.env.TYPEORM_LOGGING_RELATIVE_PATH || 'typeorm.backend.log',
+  DB_USER: process.env.DB_USER ?? 'root',
+  DB_PASSWORD: process.env.DB_PASSWORD ?? '',
+  DB_DATABASE: process.env.DB_DATABASE ?? 'gradido_community',
+  TYPEORM_LOGGING_RELATIVE_PATH: process.env.TYPEORM_LOGGING_RELATIVE_PATH ?? 'typeorm.backend.log',
 }
 
 const klicktipp = {
   KLICKTIPP: process.env.KLICKTIPP === 'true' || false,
-  KLICKTTIPP_API_URL: process.env.KLICKTIPP_API_URL || 'https://api.klicktipp.com',
-  KLICKTIPP_USER: process.env.KLICKTIPP_USER || 'gradido_test',
-  KLICKTIPP_PASSWORD: process.env.KLICKTIPP_PASSWORD || 'secret321',
-  KLICKTIPP_APIKEY_DE: process.env.KLICKTIPP_APIKEY_DE || 'SomeFakeKeyDE',
-  KLICKTIPP_APIKEY_EN: process.env.KLICKTIPP_APIKEY_EN || 'SomeFakeKeyEN',
+  KLICKTTIPP_API_URL: process.env.KLICKTIPP_API_URL ?? 'https://api.klicktipp.com',
+  KLICKTIPP_USER: process.env.KLICKTIPP_USER ?? 'gradido_test',
+  KLICKTIPP_PASSWORD: process.env.KLICKTIPP_PASSWORD ?? 'secret321',
+  KLICKTIPP_APIKEY_DE: process.env.KLICKTIPP_APIKEY_DE ?? 'SomeFakeKeyDE',
+  KLICKTIPP_APIKEY_EN: process.env.KLICKTIPP_APIKEY_EN ?? 'SomeFakeKeyEN',
 }
 
 const community = {
-  COMMUNITY_NAME: process.env.COMMUNITY_NAME || 'Gradido Entwicklung',
-  COMMUNITY_URL: process.env.COMMUNITY_URL || 'http://localhost/',
-  COMMUNITY_REGISTER_URL: process.env.COMMUNITY_REGISTER_URL || 'http://localhost/register',
-  COMMUNITY_REDEEM_URL: process.env.COMMUNITY_REDEEM_URL || 'http://localhost/redeem/{code}',
+  COMMUNITY_NAME: process.env.COMMUNITY_NAME ?? 'Gradido Entwicklung',
+  COMMUNITY_URL: process.env.COMMUNITY_URL ?? 'http://localhost/',
+  COMMUNITY_REGISTER_URL: process.env.COMMUNITY_REGISTER_URL ?? 'http://localhost/register',
+  COMMUNITY_REDEEM_URL: process.env.COMMUNITY_REDEEM_URL ?? 'http://localhost/redeem/{code}',
   COMMUNITY_REDEEM_CONTRIBUTION_URL:
-    process.env.COMMUNITY_REDEEM_CONTRIBUTION_URL || 'http://localhost/redeem/CL-{code}',
+    process.env.COMMUNITY_REDEEM_CONTRIBUTION_URL ?? 'http://localhost/redeem/CL-{code}',
   COMMUNITY_DESCRIPTION:
-    process.env.COMMUNITY_DESCRIPTION || 'Die lokale Entwicklungsumgebung von Gradido.',
-  COMMUNITY_SUPPORT_MAIL: process.env.COMMUNITY_SUPPORT_MAIL || 'support@supportmail.com',
+    process.env.COMMUNITY_DESCRIPTION ?? 'Die lokale Entwicklungsumgebung von Gradido.',
+  COMMUNITY_SUPPORT_MAIL: process.env.COMMUNITY_SUPPORT_MAIL ?? 'support@supportmail.com',
 }
 
 const loginServer = {
-  LOGIN_APP_SECRET: process.env.LOGIN_APP_SECRET || '21ffbbc616fe',
-  LOGIN_SERVER_KEY: process.env.LOGIN_SERVER_KEY || 'a51ef8ac7ef1abf162fb7a65261acd7a',
+  LOGIN_APP_SECRET: process.env.LOGIN_APP_SECRET ?? '21ffbbc616fe',
+  LOGIN_SERVER_KEY: process.env.LOGIN_SERVER_KEY ?? 'a51ef8ac7ef1abf162fb7a65261acd7a',
 }
 
 const email = {
   EMAIL: process.env.EMAIL === 'true' || false,
   EMAIL_TEST_MODUS: process.env.EMAIL_TEST_MODUS === 'true' || false,
-  EMAIL_TEST_RECEIVER: process.env.EMAIL_TEST_RECEIVER || 'stage1@gradido.net',
-  EMAIL_USERNAME: process.env.EMAIL_USERNAME || '',
-  EMAIL_SENDER: process.env.EMAIL_SENDER || 'info@gradido.net',
-  EMAIL_PASSWORD: process.env.EMAIL_PASSWORD || '',
-  EMAIL_SMTP_URL: process.env.EMAIL_SMTP_URL || 'mailserver',
+  EMAIL_TEST_RECEIVER: process.env.EMAIL_TEST_RECEIVER ?? 'stage1@gradido.net',
+  EMAIL_USERNAME: process.env.EMAIL_USERNAME ?? '',
+  EMAIL_SENDER: process.env.EMAIL_SENDER ?? 'info@gradido.net',
+  EMAIL_PASSWORD: process.env.EMAIL_PASSWORD ?? '',
+  EMAIL_SMTP_URL: process.env.EMAIL_SMTP_URL ?? 'mailserver',
   EMAIL_SMTP_PORT: Number(process.env.EMAIL_SMTP_PORT) || 1025,
   // eslint-disable-next-line no-unneeded-ternary
   EMAIL_TLS: process.env.EMAIL_TLS === 'false' ? false : true,
   EMAIL_LINK_VERIFICATION:
-    process.env.EMAIL_LINK_VERIFICATION || 'http://localhost/checkEmail/{optin}{code}',
+    process.env.EMAIL_LINK_VERIFICATION ?? 'http://localhost/checkEmail/{optin}{code}',
   EMAIL_LINK_SETPASSWORD:
-    process.env.EMAIL_LINK_SETPASSWORD || 'http://localhost/reset-password/{optin}',
+    process.env.EMAIL_LINK_SETPASSWORD ?? 'http://localhost/reset-password/{optin}',
   EMAIL_LINK_FORGOTPASSWORD:
-    process.env.EMAIL_LINK_FORGOTPASSWORD || 'http://localhost/forgot-password',
-  EMAIL_LINK_OVERVIEW: process.env.EMAIL_LINK_OVERVIEW || 'http://localhost/overview',
+    process.env.EMAIL_LINK_FORGOTPASSWORD ?? 'http://localhost/forgot-password',
+  EMAIL_LINK_OVERVIEW: process.env.EMAIL_LINK_OVERVIEW ?? 'http://localhost/overview',
   // time in minutes a optin code is valid
   EMAIL_CODE_VALID_TIME: process.env.EMAIL_CODE_VALID_TIME
     ? parseInt(process.env.EMAIL_CODE_VALID_TIME) || 1440
@@ -98,14 +98,14 @@ const email = {
 
 const webhook = {
   // Elopage
-  WEBHOOK_ELOPAGE_SECRET: process.env.WEBHOOK_ELOPAGE_SECRET || 'secret',
+  WEBHOOK_ELOPAGE_SECRET: process.env.WEBHOOK_ELOPAGE_SECRET ?? 'secret',
 }
 
 // This is needed by graphql-directive-auth
 process.env.APP_SECRET = server.JWT_SECRET
 
 // Check config version
-constants.CONFIG_VERSION.CURRENT = process.env.CONFIG_VERSION || constants.CONFIG_VERSION.DEFAULT
+constants.CONFIG_VERSION.CURRENT = process.env.CONFIG_VERSION ?? constants.CONFIG_VERSION.DEFAULT
 if (
   ![constants.CONFIG_VERSION.EXPECTED, constants.CONFIG_VERSION.DEFAULT].includes(
     constants.CONFIG_VERSION.CURRENT,
diff --git a/backend/src/federation/client/1_0/FederationClient.ts b/backend/src/federation/client/1_0/FederationClient.ts
index 743d17348..ba446abe8 100644
--- a/backend/src/federation/client/1_0/FederationClient.ts
+++ b/backend/src/federation/client/1_0/FederationClient.ts
@@ -1,44 +1,49 @@
-/* eslint-disable @typescript-eslint/no-unsafe-member-access */
-/* eslint-disable @typescript-eslint/no-unsafe-return */
-/* eslint-disable @typescript-eslint/no-unsafe-assignment */
 import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
-import { gql } from 'graphql-request'
+import { GraphQLClient } from 'graphql-request'
 
-import { GraphQLGetClient } from '@/federation/client/GraphQLGetClient'
-import { LogError } from '@/server/LogError'
+import { getPublicKey } from '@/federation/client/1_0/query/getPublicKey'
 import { backendLogger as logger } from '@/server/logger'
 
-export async function requestGetPublicKey(
-  dbCom: DbFederatedCommunity,
-): Promise<string | undefined> {
-  let endpoint = dbCom.endPoint.endsWith('/') ? dbCom.endPoint : dbCom.endPoint + '/'
-  endpoint = `${endpoint}${dbCom.apiVersion}/`
-  logger.info(`requestGetPublicKey with endpoint='${endpoint}'...`)
+// eslint-disable-next-line camelcase
+export class FederationClient {
+  dbCom: DbFederatedCommunity
+  endpoint: string
+  client: GraphQLClient
 
-  const graphQLClient = GraphQLGetClient.getInstance(endpoint)
-  logger.debug(`graphQLClient=${JSON.stringify(graphQLClient)}`)
-  const query = gql`
-    query {
-      getPublicKey {
-        publicKey
+  constructor(dbCom: DbFederatedCommunity) {
+    this.dbCom = dbCom
+    this.endpoint = `${dbCom.endPoint.endsWith('/') ? dbCom.endPoint : dbCom.endPoint + '/'}${
+      dbCom.apiVersion
+    }/`
+    this.client = new GraphQLClient(this.endpoint, {
+      method: 'GET',
+      jsonSerializer: {
+        parse: JSON.parse,
+        stringify: JSON.stringify,
+      },
+    })
+  }
+
+  getPublicKey = async (): Promise<string | undefined> => {
+    logger.info('Federation: getPublicKey from endpoint', this.endpoint)
+    try {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+      const { data } = await this.client.rawRequest(getPublicKey, {})
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+      if (!data?.getPublicKey?.publicKey) {
+        logger.warn('Federation: getPublicKey without response data from endpoint', this.endpoint)
+        return
       }
-    }
-  `
-  const variables = {}
-
-  try {
-    const { data, errors, extensions, headers, status } = await graphQLClient.rawRequest(
-      query,
-      variables,
-    )
-    logger.debug(`Response-Data:`, data, errors, extensions, headers, status)
-    if (data) {
-      logger.debug(`Response-PublicKey:`, data.getPublicKey.publicKey)
-      logger.info(`requestGetPublicKey processed successfully`)
+      logger.info(
+        'Federation: getPublicKey successful from endpoint',
+        this.endpoint,
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+        data.getPublicKey.publicKey,
+      )
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-return, @typescript-eslint/no-unsafe-member-access
       return data.getPublicKey.publicKey
+    } catch (err) {
+      logger.warn('Federation: getPublicKey failed for endpoint', this.endpoint)
     }
-    logger.warn(`requestGetPublicKey processed without response data`)
-  } catch (err) {
-    throw new LogError(`Request-Error:`, err)
   }
 }
diff --git a/backend/src/federation/client/1_0/query/getPublicKey.ts b/backend/src/federation/client/1_0/query/getPublicKey.ts
new file mode 100644
index 000000000..a772a0cf1
--- /dev/null
+++ b/backend/src/federation/client/1_0/query/getPublicKey.ts
@@ -0,0 +1,9 @@
+import { gql } from 'graphql-request'
+
+export const getPublicKey = gql`
+  query {
+    getPublicKey {
+      publicKey
+    }
+  }
+`
diff --git a/backend/src/federation/client/1_1/FederationClient.ts b/backend/src/federation/client/1_1/FederationClient.ts
index 35c88bf3b..2fdfedd92 100644
--- a/backend/src/federation/client/1_1/FederationClient.ts
+++ b/backend/src/federation/client/1_1/FederationClient.ts
@@ -1,44 +1,5 @@
-/* eslint-disable @typescript-eslint/no-unsafe-return */
-/* eslint-disable @typescript-eslint/no-unsafe-assignment */
-/* eslint-disable @typescript-eslint/no-unsafe-member-access */
-import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
-import { gql } from 'graphql-request'
+// eslint-disable-next-line camelcase
+import { FederationClient as V1_0_FederationClient } from '@/federation/client/1_0/FederationClient'
 
-import { GraphQLGetClient } from '@/federation/client/GraphQLGetClient'
-import { LogError } from '@/server/LogError'
-import { backendLogger as logger } from '@/server/logger'
-
-export async function requestGetPublicKey(
-  dbCom: DbFederatedCommunity,
-): Promise<string | undefined> {
-  let endpoint = dbCom.endPoint.endsWith('/') ? dbCom.endPoint : dbCom.endPoint + '/'
-  endpoint = `${endpoint}${dbCom.apiVersion}/`
-  logger.info(`requestGetPublicKey with endpoint='${endpoint}'...`)
-
-  const graphQLClient = GraphQLGetClient.getInstance(endpoint)
-  logger.debug(`graphQLClient=${JSON.stringify(graphQLClient)}`)
-  const query = gql`
-    query {
-      getPublicKey {
-        publicKey
-      }
-    }
-  `
-  const variables = {}
-
-  try {
-    const { data, errors, extensions, headers, status } = await graphQLClient.rawRequest(
-      query,
-      variables,
-    )
-    logger.debug(`Response-Data:`, data, errors, extensions, headers, status)
-    if (data) {
-      logger.debug(`Response-PublicKey:`, data.getPublicKey.publicKey)
-      logger.info(`requestGetPublicKey processed successfully`)
-      return data.getPublicKey.publicKey
-    }
-    logger.warn(`requestGetPublicKey processed without response data`)
-  } catch (err) {
-    throw new LogError(`Request-Error:`, err)
-  }
-}
+// eslint-disable-next-line camelcase
+export class FederationClient extends V1_0_FederationClient {}
diff --git a/backend/src/federation/client/FederationClientFactory.ts b/backend/src/federation/client/FederationClientFactory.ts
new file mode 100644
index 000000000..d057ffd04
--- /dev/null
+++ b/backend/src/federation/client/FederationClientFactory.ts
@@ -0,0 +1,62 @@
+import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
+
+// eslint-disable-next-line camelcase
+import { FederationClient as V1_0_FederationClient } from '@/federation/client/1_0/FederationClient'
+// eslint-disable-next-line camelcase
+import { FederationClient as V1_1_FederationClient } from '@/federation/client/1_1/FederationClient'
+import { ApiVersionType } from '@/federation/enum/apiVersionType'
+
+// eslint-disable-next-line camelcase
+type FederationClient = V1_0_FederationClient | V1_1_FederationClient
+
+interface FederationClientInstance {
+  id: number
+  // eslint-disable-next-line no-use-before-define
+  client: FederationClient
+}
+
+// eslint-disable-next-line @typescript-eslint/no-extraneous-class
+export class FederationClientFactory {
+  private static instanceArray: FederationClientInstance[] = []
+
+  /**
+   * The Singleton's constructor should always be private to prevent direct
+   * construction calls with the `new` operator.
+   */
+  // eslint-disable-next-line no-useless-constructor, @typescript-eslint/no-empty-function
+  private constructor() {}
+
+  private static createFederationClient = (dbCom: DbFederatedCommunity) => {
+    switch (dbCom.apiVersion) {
+      case ApiVersionType.V1_0:
+        return new V1_0_FederationClient(dbCom)
+      case ApiVersionType.V1_1:
+        return new V1_1_FederationClient(dbCom)
+      default:
+        return null
+    }
+  }
+
+  /**
+   * The static method that controls the access to the singleton instance.
+   *
+   * This implementation let you subclass the Singleton class while keeping
+   * just one instance of each subclass around.
+   */
+  public static getInstance(dbCom: DbFederatedCommunity): FederationClient | null {
+    const instance = FederationClientFactory.instanceArray.find(
+      (instance) => instance.id === dbCom.id,
+    )
+    if (instance) {
+      return instance.client
+    }
+    const client = FederationClientFactory.createFederationClient(dbCom)
+    if (client) {
+      FederationClientFactory.instanceArray.push({
+        id: dbCom.id,
+        client,
+      } as FederationClientInstance)
+    }
+    return client
+  }
+}
diff --git a/backend/src/federation/client/GraphQLGetClient.ts b/backend/src/federation/client/GraphQLGetClient.ts
deleted file mode 100644
index 2f5281532..000000000
--- a/backend/src/federation/client/GraphQLGetClient.ts
+++ /dev/null
@@ -1,43 +0,0 @@
-import { GraphQLClient } from 'graphql-request'
-import { PatchedRequestInit } from 'graphql-request/dist/types'
-
-type ClientInstance = {
-  url: string
-  // eslint-disable-next-line no-use-before-define
-  client: GraphQLGetClient
-}
-
-export class GraphQLGetClient extends GraphQLClient {
-  private static instanceArray: ClientInstance[] = []
-
-  /**
-   * The Singleton's constructor should always be private to prevent direct
-   * construction calls with the `new` operator.
-   */
-  // eslint-disable-next-line no-useless-constructor
-  private constructor(url: string, options?: PatchedRequestInit) {
-    super(url, options)
-  }
-
-  /**
-   * The static method that controls the access to the singleton instance.
-   *
-   * This implementation let you subclass the Singleton class while keeping
-   * just one instance of each subclass around.
-   */
-  public static getInstance(url: string): GraphQLGetClient {
-    const instance = GraphQLGetClient.instanceArray.find((instance) => instance.url === url)
-    if (instance) {
-      return instance.client
-    }
-    const client = new GraphQLGetClient(url, {
-      method: 'GET',
-      jsonSerializer: {
-        parse: JSON.parse,
-        stringify: JSON.stringify,
-      },
-    })
-    GraphQLGetClient.instanceArray.push({ url, client } as ClientInstance)
-    return client
-  }
-}
diff --git a/backend/src/federation/validateCommunities.test.ts b/backend/src/federation/validateCommunities.test.ts
index ed4897e09..834f37e16 100644
--- a/backend/src/federation/validateCommunities.test.ts
+++ b/backend/src/federation/validateCommunities.test.ts
@@ -8,6 +8,8 @@
 import { Connection } from '@dbTools/typeorm'
 import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
 import { ApolloServerTestClient } from 'apollo-server-testing'
+import { GraphQLClient } from 'graphql-request'
+import { Response } from 'graphql-request/dist/types'
 
 import { testEnvironment, cleanDB } from '@test/helpers'
 import { logger } from '@test/testSetup'
@@ -57,10 +59,23 @@ describe('validate Communities', () => {
       expect(logger.debug).toBeCalledWith(`Federation: found 0 dbCommunities`)
     })
 
-    describe('with one Community of api 1_0', () => {
+    describe('with one Community of api 1_0 and not matching pubKey', () => {
       beforeEach(async () => {
+        // eslint-disable-next-line @typescript-eslint/require-await
+        jest.spyOn(GraphQLClient.prototype, 'rawRequest').mockImplementation(async () => {
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-return
+          return {
+            data: {
+              getPublicKey: {
+                publicKey: 'somePubKey',
+              },
+            },
+          } as Response<unknown>
+        })
         const variables1 = {
-          publicKey: Buffer.from('11111111111111111111111111111111'),
+          publicKey: Buffer.from(
+            '1111111111111111111111111111111111111111111111111111111111111111',
+          ),
           apiVersion: '1_0',
           endPoint: 'http//localhost:5001/api/',
           lastAnnouncedAt: new Date(),
@@ -70,6 +85,7 @@ describe('validate Communities', () => {
           .into(DbFederatedCommunity)
           .values(variables1)
           .orUpdate({
+            // eslint-disable-next-line camelcase
             conflict_target: ['id', 'publicKey', 'apiVersion'],
             overwrite: ['end_point', 'last_announced_at'],
           })
@@ -84,14 +100,89 @@ describe('validate Communities', () => {
       })
       it('logs requestGetPublicKey for community api 1_0 ', () => {
         expect(logger.info).toBeCalledWith(
-          `requestGetPublicKey with endpoint='http//localhost:5001/api/1_0/'...`,
+          'Federation: getPublicKey from endpoint',
+          'http//localhost:5001/api/1_0/',
+        )
+      })
+      it('logs not matching publicKeys', () => {
+        expect(logger.warn).toBeCalledWith(
+          'Federation: received not matching publicKey:',
+          'somePubKey',
+          expect.stringMatching('1111111111111111111111111111111111111111111111111111111111111111'),
+        )
+      })
+    })
+    describe('with one Community of api 1_0 and matching pubKey', () => {
+      beforeEach(async () => {
+        // eslint-disable-next-line @typescript-eslint/require-await
+        jest.spyOn(GraphQLClient.prototype, 'rawRequest').mockImplementation(async () => {
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-return
+          return {
+            data: {
+              getPublicKey: {
+                publicKey: '1111111111111111111111111111111111111111111111111111111111111111',
+              },
+            },
+          } as Response<unknown>
+        })
+        const variables1 = {
+          publicKey: Buffer.from(
+            '1111111111111111111111111111111111111111111111111111111111111111',
+          ),
+          apiVersion: '1_0',
+          endPoint: 'http//localhost:5001/api/',
+          lastAnnouncedAt: new Date(),
+        }
+        await DbFederatedCommunity.createQueryBuilder()
+          .insert()
+          .into(DbFederatedCommunity)
+          .values(variables1)
+          .orUpdate({
+            // eslint-disable-next-line camelcase
+            conflict_target: ['id', 'publicKey', 'apiVersion'],
+            overwrite: ['end_point', 'last_announced_at'],
+          })
+          .execute()
+        await DbFederatedCommunity.update({}, { verifiedAt: null })
+        jest.clearAllMocks()
+        await validateCommunities()
+      })
+
+      it('logs one community found', () => {
+        expect(logger.debug).toBeCalledWith(`Federation: found 1 dbCommunities`)
+      })
+      it('logs requestGetPublicKey for community api 1_0 ', () => {
+        expect(logger.info).toBeCalledWith(
+          'Federation: getPublicKey from endpoint',
+          'http//localhost:5001/api/1_0/',
+        )
+      })
+      it('logs community pubKey verified', () => {
+        expect(logger.info).toHaveBeenNthCalledWith(
+          3,
+          'Federation: verified community with',
+          'http//localhost:5001/api/',
         )
       })
     })
     describe('with two Communities of api 1_0 and 1_1', () => {
       beforeEach(async () => {
+        jest.clearAllMocks()
+        // eslint-disable-next-line @typescript-eslint/require-await
+        jest.spyOn(GraphQLClient.prototype, 'rawRequest').mockImplementation(async () => {
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-return
+          return {
+            data: {
+              getPublicKey: {
+                publicKey: '1111111111111111111111111111111111111111111111111111111111111111',
+              },
+            },
+          } as Response<unknown>
+        })
         const variables2 = {
-          publicKey: Buffer.from('11111111111111111111111111111111'),
+          publicKey: Buffer.from(
+            '1111111111111111111111111111111111111111111111111111111111111111',
+          ),
           apiVersion: '1_1',
           endPoint: 'http//localhost:5001/api/',
           lastAnnouncedAt: new Date(),
@@ -101,11 +192,13 @@ describe('validate Communities', () => {
           .into(DbFederatedCommunity)
           .values(variables2)
           .orUpdate({
+            // eslint-disable-next-line camelcase
             conflict_target: ['id', 'publicKey', 'apiVersion'],
             overwrite: ['end_point', 'last_announced_at'],
           })
           .execute()
 
+        await DbFederatedCommunity.update({}, { verifiedAt: null })
         jest.clearAllMocks()
         await validateCommunities()
       })
@@ -114,12 +207,14 @@ describe('validate Communities', () => {
       })
       it('logs requestGetPublicKey for community api 1_0 ', () => {
         expect(logger.info).toBeCalledWith(
-          `requestGetPublicKey with endpoint='http//localhost:5001/api/1_0/'...`,
+          'Federation: getPublicKey from endpoint',
+          'http//localhost:5001/api/1_0/',
         )
       })
       it('logs requestGetPublicKey for community api 1_1 ', () => {
         expect(logger.info).toBeCalledWith(
-          `requestGetPublicKey with endpoint='http//localhost:5001/api/1_1/'...`,
+          'Federation: getPublicKey from endpoint',
+          'http//localhost:5001/api/1_1/',
         )
       })
     })
@@ -127,7 +222,9 @@ describe('validate Communities', () => {
       let dbCom: DbFederatedCommunity
       beforeEach(async () => {
         const variables3 = {
-          publicKey: Buffer.from('11111111111111111111111111111111'),
+          publicKey: Buffer.from(
+            '1111111111111111111111111111111111111111111111111111111111111111',
+          ),
           apiVersion: '2_0',
           endPoint: 'http//localhost:5001/api/',
           lastAnnouncedAt: new Date(),
@@ -137,6 +234,7 @@ describe('validate Communities', () => {
           .into(DbFederatedCommunity)
           .values(variables3)
           .orUpdate({
+            // eslint-disable-next-line camelcase
             conflict_target: ['id', 'publicKey', 'apiVersion'],
             overwrite: ['end_point', 'last_announced_at'],
           })
@@ -144,6 +242,7 @@ describe('validate Communities', () => {
         dbCom = await DbFederatedCommunity.findOneOrFail({
           where: { publicKey: variables3.publicKey, apiVersion: variables3.apiVersion },
         })
+        await DbFederatedCommunity.update({}, { verifiedAt: null })
         jest.clearAllMocks()
         await validateCommunities()
       })
@@ -152,18 +251,21 @@ describe('validate Communities', () => {
       })
       it('logs requestGetPublicKey for community api 1_0 ', () => {
         expect(logger.info).toBeCalledWith(
-          `requestGetPublicKey with endpoint='http//localhost:5001/api/1_0/'...`,
+          'Federation: getPublicKey from endpoint',
+          'http//localhost:5001/api/1_0/',
         )
       })
       it('logs requestGetPublicKey for community api 1_1 ', () => {
         expect(logger.info).toBeCalledWith(
-          `requestGetPublicKey with endpoint='http//localhost:5001/api/1_1/'...`,
+          'Federation: getPublicKey from endpoint',
+          'http//localhost:5001/api/1_1/',
         )
       })
       it('logs unsupported api for community with api 2_0 ', () => {
         expect(logger.warn).toBeCalledWith(
-          `Federation: dbCom: ${dbCom.id} with unsupported apiVersion=2_0; supported versions`,
-          ['1_0', '1_1'],
+          'Federation: dbCom with unsupported apiVersion',
+          dbCom.endPoint,
+          '2_0',
         )
       })
     })
diff --git a/backend/src/federation/validateCommunities.ts b/backend/src/federation/validateCommunities.ts
index b38f38ee9..91c6ee724 100644
--- a/backend/src/federation/validateCommunities.ts
+++ b/backend/src/federation/validateCommunities.ts
@@ -3,13 +3,11 @@
 import { IsNull } from '@dbTools/typeorm'
 import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
 
-import { LogError } from '@/server/LogError'
+// eslint-disable-next-line camelcase
+import { FederationClient as V1_0_FederationClient } from '@/federation/client/1_0/FederationClient'
+import { FederationClientFactory } from '@/federation/client/FederationClientFactory'
 import { backendLogger as logger } from '@/server/logger'
 
-// eslint-disable-next-line camelcase
-import { requestGetPublicKey as v1_0_requestGetPublicKey } from './client/1_0/FederationClient'
-// eslint-disable-next-line camelcase
-import { requestGetPublicKey as v1_1_requestGetPublicKey } from './client/1_1/FederationClient'
 import { ApiVersionType } from './enum/apiVersionType'
 
 export function startValidateCommunities(timerInterval: number): void {
@@ -36,56 +34,28 @@ export async function validateCommunities(): Promise<void> {
     logger.debug('Federation: dbCom', dbCom)
     const apiValueStrings: string[] = Object.values(ApiVersionType)
     logger.debug(`suppported ApiVersions=`, apiValueStrings)
-    if (apiValueStrings.includes(dbCom.apiVersion)) {
-      logger.debug(
-        `Federation: validate publicKey for dbCom: ${dbCom.id} with apiVersion=${dbCom.apiVersion}`,
-      )
-      try {
-        const pubKey = await invokeVersionedRequestGetPublicKey(dbCom)
-        logger.info(
-          'Federation: received publicKey from endpoint',
-          pubKey,
-          `${dbCom.endPoint}/${dbCom.apiVersion}`,
-        )
+    if (!apiValueStrings.includes(dbCom.apiVersion)) {
+      logger.warn('Federation: dbCom with unsupported apiVersion', dbCom.endPoint, dbCom.apiVersion)
+      continue
+    }
+    try {
+      const client = FederationClientFactory.getInstance(dbCom)
+      // eslint-disable-next-line camelcase
+      if (client instanceof V1_0_FederationClient) {
+        const pubKey = await client.getPublicKey()
         if (pubKey && pubKey === dbCom.publicKey.toString()) {
-          logger.info(`Federation: matching publicKey:  ${pubKey}`)
           await DbFederatedCommunity.update({ id: dbCom.id }, { verifiedAt: new Date() })
-          logger.debug(`Federation: updated dbCom:  ${JSON.stringify(dbCom)}`)
+          logger.info('Federation: verified community with', dbCom.endPoint)
         } else {
           logger.warn(
-            `Federation: received not matching publicKey -> received: ${
-              pubKey || 'null'
-            }, expected: ${dbCom.publicKey.toString()} `,
+            'Federation: received not matching publicKey:',
+            pubKey,
+            dbCom.publicKey.toString(),
           )
-          // DbCommunity.delete({ id: dbCom.id })
-        }
-      } catch (err) {
-        if (!isLogError(err)) {
-          logger.error(`Error:`, err)
         }
       }
-    } else {
-      logger.warn(
-        `Federation: dbCom: ${dbCom.id} with unsupported apiVersion=${dbCom.apiVersion}; supported versions`,
-        apiValueStrings,
-      )
+    } catch (err) {
+      logger.error(`Error:`, err)
     }
   }
 }
-
-function isLogError(err: unknown) {
-  return err instanceof LogError
-}
-
-async function invokeVersionedRequestGetPublicKey(
-  dbCom: DbFederatedCommunity,
-): Promise<string | undefined> {
-  switch (dbCom.apiVersion) {
-    case ApiVersionType.V1_0:
-      return v1_0_requestGetPublicKey(dbCom)
-    case ApiVersionType.V1_1:
-      return v1_1_requestGetPublicKey(dbCom)
-    default:
-      return undefined
-  }
-}
diff --git a/backend/src/graphql/arg/UpdateUserInfosArgs.ts b/backend/src/graphql/arg/UpdateUserInfosArgs.ts
index 2f9df8dd7..e57d4ec82 100644
--- a/backend/src/graphql/arg/UpdateUserInfosArgs.ts
+++ b/backend/src/graphql/arg/UpdateUserInfosArgs.ts
@@ -8,6 +8,9 @@ export class UpdateUserInfosArgs {
   @Field({ nullable: true })
   lastName?: string
 
+  @Field({ nullable: true })
+  alias?: string
+
   @Field({ nullable: true })
   language?: string
 
diff --git a/backend/src/graphql/directive/isAuthorized.ts b/backend/src/graphql/directive/isAuthorized.ts
index b8595a2bd..e41f41151 100644
--- a/backend/src/graphql/directive/isAuthorized.ts
+++ b/backend/src/graphql/directive/isAuthorized.ts
@@ -12,7 +12,7 @@ export const isAuthorized: AuthChecker<Context> = async ({ context }, rights) =>
   context.role = ROLE_UNAUTHORIZED // unauthorized user
 
   // is rights an inalienable right?
-  if ((<RIGHTS[]>rights).reduce((acc, right) => acc && INALIENABLE_RIGHTS.includes(right), true))
+  if ((rights as RIGHTS[]).reduce((acc, right) => acc && INALIENABLE_RIGHTS.includes(right), true))
     return true
 
   // Do we have a token?
@@ -21,7 +21,7 @@ export const isAuthorized: AuthChecker<Context> = async ({ context }, rights) =>
   }
 
   // Decode the token
-  const decoded = decode(context.token)
+  const decoded = await decode(context.token)
   if (!decoded) {
     throw new LogError('403.13 - Client certificate revoked')
   }
@@ -43,12 +43,12 @@ export const isAuthorized: AuthChecker<Context> = async ({ context }, rights) =>
   }
 
   // check for correct rights
-  const missingRights = (<RIGHTS[]>rights).filter((right) => !context.role?.hasRight(right))
+  const missingRights = (rights as RIGHTS[]).filter((right) => !context.role?.hasRight(right))
   if (missingRights.length !== 0) {
     throw new LogError('401 Unauthorized')
   }
 
   // set new header token
-  context.setHeaders.push({ key: 'token', value: encode(decoded.gradidoID) })
+  context.setHeaders.push({ key: 'token', value: await encode(decoded.gradidoID) })
   return true
 }
diff --git a/backend/src/graphql/model/Balance.ts b/backend/src/graphql/model/Balance.ts
index 162ccc3c0..d992677b1 100644
--- a/backend/src/graphql/model/Balance.ts
+++ b/backend/src/graphql/model/Balance.ts
@@ -10,7 +10,7 @@ export class Balance {
     linkCount: number
   }) {
     this.balance = data.balance
-    this.balanceGDT = data.balanceGDT || null
+    this.balanceGDT = data.balanceGDT ?? null
     this.count = data.count
     this.linkCount = data.linkCount
   }
diff --git a/backend/src/graphql/model/Transaction.ts b/backend/src/graphql/model/Transaction.ts
index 3334dea84..bfc96089b 100644
--- a/backend/src/graphql/model/Transaction.ts
+++ b/backend/src/graphql/model/Transaction.ts
@@ -43,13 +43,12 @@ export class Transaction {
     this.memo = transaction.memo
     this.creationDate = transaction.creationDate
     this.linkedUser = linkedUser
-    this.linkedTransactionId = transaction.linkedTransactionId || null
+    this.linkedTransactionId = transaction.linkedTransactionId ?? null
     this.linkId = transaction.contribution
       ? transaction.contribution.contributionLinkId
-      : transaction.transactionLinkId || null
+      : transaction.transactionLinkId ?? null
     this.previousBalance =
-      (transaction.previousTransaction &&
-        transaction.previousTransaction.balance.toDecimalPlaces(2, Decimal.ROUND_DOWN)) ||
+      transaction.previousTransaction?.balance.toDecimalPlaces(2, Decimal.ROUND_DOWN) ??
       new Decimal(0)
   }
 
diff --git a/backend/src/graphql/model/User.ts b/backend/src/graphql/model/User.ts
index c705ba912..5abbdadb7 100644
--- a/backend/src/graphql/model/User.ts
+++ b/backend/src/graphql/model/User.ts
@@ -2,7 +2,6 @@ import { User as dbUser } from '@entity/User'
 import { ObjectType, Field, Int } from 'type-graphql'
 
 import { KlickTipp } from './KlickTipp'
-import { UserContact } from './UserContact'
 
 @ObjectType()
 export class User {
@@ -10,10 +9,7 @@ export class User {
     this.id = user.id
     this.gradidoID = user.gradidoID
     this.alias = user.alias
-    this.emailId = user.emailId
     if (user.emailContact) {
-      this.email = user.emailContact.email
-      this.emailContact = new UserContact(user.emailContact)
       this.emailChecked = user.emailContact.emailChecked
     }
     this.firstName = user.firstName
@@ -38,16 +34,6 @@ export class User {
   @Field(() => String, { nullable: true })
   alias: string | null
 
-  @Field(() => Int, { nullable: true })
-  emailId: number | null
-
-  // TODO privacy issue here
-  @Field(() => String, { nullable: true })
-  email: string | null
-
-  @Field(() => UserContact)
-  emailContact: UserContact
-
   @Field(() => String, { nullable: true })
   firstName: string | null
 
diff --git a/backend/src/graphql/resolver/BalanceResolver.ts b/backend/src/graphql/resolver/BalanceResolver.ts
index deedb9dff..c8fdacdcf 100644
--- a/backend/src/graphql/resolver/BalanceResolver.ts
+++ b/backend/src/graphql/resolver/BalanceResolver.ts
@@ -70,7 +70,10 @@ export class BalanceResolver {
       now,
     )
     logger.info(
-      `calculatedDecay(balance=${lastTransaction.balance}, balanceDate=${lastTransaction.balanceDate})=${calculatedDecay}`,
+      'calculatedDecay',
+      lastTransaction.balance,
+      lastTransaction.balanceDate,
+      calculatedDecay,
     )
 
     // The final balance is reduced by the link amount withheld
@@ -96,9 +99,7 @@ export class BalanceResolver {
       count,
       linkCount,
     })
-    logger.info(
-      `new Balance(balance=${balance}, balanceGDT=${balanceGDT}, count=${count}, linkCount=${linkCount}) = ${newBalance}`,
-    )
+    logger.info('new Balance', balance, balanceGDT, count, linkCount, newBalance)
 
     return newBalance
   }
diff --git a/backend/src/graphql/resolver/ContributionResolver.test.ts b/backend/src/graphql/resolver/ContributionResolver.test.ts
index 17c739fcb..d4c84b4f3 100644
--- a/backend/src/graphql/resolver/ContributionResolver.test.ts
+++ b/backend/src/graphql/resolver/ContributionResolver.test.ts
@@ -66,7 +66,7 @@ let testEnv: {
   query: ApolloServerTestClient['query']
   con: Connection
 }
-let creation: Contribution | void
+let creation: Contribution | null
 let admin: User
 let pendingContribution: any
 let inProgressContribution: any
@@ -2071,7 +2071,7 @@ describe('ContributionResolver', () => {
                     mutate({
                       mutation: updateContribution,
                       variables: {
-                        contributionId: (adminContribution && adminContribution.id) || -1,
+                        contributionId: adminContribution?.id ?? -1,
                         amount: 100.0,
                         memo: 'Test Test Test',
                         creationDate: new Date().toString(),
@@ -2565,8 +2565,8 @@ describe('ContributionResolver', () => {
           })
 
           describe('confirm two creations one after the other quickly', () => {
-            let c1: Contribution | void
-            let c2: Contribution | void
+            let c1: Contribution | null
+            let c2: Contribution | null
 
             beforeAll(async () => {
               const now = new Date()
diff --git a/backend/src/graphql/resolver/ContributionResolver.ts b/backend/src/graphql/resolver/ContributionResolver.ts
index 1884fecc4..fa1590523 100644
--- a/backend/src/graphql/resolver/ContributionResolver.ts
+++ b/backend/src/graphql/resolver/ContributionResolver.ts
@@ -43,6 +43,7 @@ import { LogError } from '@/server/LogError'
 import { backendLogger as logger } from '@/server/logger'
 import { calculateDecay } from '@/util/decay'
 import { TRANSACTIONS_LOCK } from '@/util/TRANSACTIONS_LOCK'
+import { fullName } from '@/util/utilities'
 
 import { MEMO_MAX_CHARS, MEMO_MIN_CHARS } from './const/const'
 import {
@@ -269,7 +270,7 @@ export class ContributionResolver {
       withDeleted: true,
       relations: ['user'],
     })
-    if (!emailContact || !emailContact.user) {
+    if (!emailContact?.user) {
       throw new LogError('Could not find user', email)
     }
     if (emailContact.deletedAt || emailContact.user.deletedAt) {
@@ -500,6 +501,8 @@ export class ContributionResolver {
         transaction.typeId = TransactionTypeId.CREATION
         transaction.memo = contribution.memo
         transaction.userId = contribution.userId
+        transaction.userGradidoID = user.gradidoID
+        transaction.userName = fullName(user.firstName, user.lastName)
         transaction.previous = lastTransaction ? lastTransaction.id : null
         transaction.amount = contribution.amount
         transaction.creationDate = contribution.contributionDate
diff --git a/backend/src/graphql/resolver/KlicktippResolver.ts b/backend/src/graphql/resolver/KlicktippResolver.ts
index 6875abcc5..81290bdb6 100644
--- a/backend/src/graphql/resolver/KlicktippResolver.ts
+++ b/backend/src/graphql/resolver/KlicktippResolver.ts
@@ -1,6 +1,6 @@
 import { Resolver, Authorized, Mutation, Ctx } from 'type-graphql'
 
-import { unsubscribe, klicktippSignIn } from '@/apis/KlicktippController'
+import { unsubscribe, subscribe } from '@/apis/KlicktippController'
 import { RIGHTS } from '@/auth/RIGHTS'
 import { EVENT_NEWSLETTER_SUBSCRIBE, EVENT_NEWSLETTER_UNSUBSCRIBE } from '@/event/Events'
 import { Context, getUser } from '@/server/context'
@@ -20,6 +20,6 @@ export class KlicktippResolver {
   async subscribeNewsletter(@Ctx() context: Context): Promise<boolean> {
     const user = getUser(context)
     await EVENT_NEWSLETTER_SUBSCRIBE(user)
-    return klicktippSignIn(user.emailContact.email, user.language)
+    return subscribe(user.emailContact.email, user.language)
   }
 }
diff --git a/backend/src/graphql/resolver/TransactionLinkResolver.test.ts b/backend/src/graphql/resolver/TransactionLinkResolver.test.ts
index 04df0dc86..3c6ba31ab 100644
--- a/backend/src/graphql/resolver/TransactionLinkResolver.test.ts
+++ b/backend/src/graphql/resolver/TransactionLinkResolver.test.ts
@@ -817,8 +817,8 @@ describe('TransactionLinkResolver', () => {
           const bibisTransaktionLinks = transactionLinks.filter(
             (transactionLink) => transactionLink.email === 'bibi@bloxberg.de',
           )
-          for (let i = 0; i < bibisTransaktionLinks.length; i++) {
-            await transactionLinkFactory(testEnv, bibisTransaktionLinks[i])
+          for (const bibisTransaktionLink of bibisTransaktionLinks) {
+            await transactionLinkFactory(testEnv, bibisTransaktionLink)
           }
 
           // admin: only now log in
@@ -1040,6 +1040,7 @@ describe('TransactionLinkResolver', () => {
     })
 
     it('returns a string that ends with the hex value of date', () => {
+      // eslint-disable-next-line security/detect-non-literal-regexp
       const regexp = new RegExp(date.getTime().toString(16) + '$')
       expect(transactionLinkCode(date)).toEqual(expect.stringMatching(regexp))
     })
diff --git a/backend/src/graphql/resolver/TransactionLinkResolver.ts b/backend/src/graphql/resolver/TransactionLinkResolver.ts
index ab322a50b..d6649814a 100644
--- a/backend/src/graphql/resolver/TransactionLinkResolver.ts
+++ b/backend/src/graphql/resolver/TransactionLinkResolver.ts
@@ -34,6 +34,7 @@ import { LogError } from '@/server/LogError'
 import { backendLogger as logger } from '@/server/logger'
 import { calculateDecay } from '@/util/decay'
 import { TRANSACTIONS_LOCK } from '@/util/TRANSACTIONS_LOCK'
+import { fullName } from '@/util/utilities'
 import { calculateBalance } from '@/util/validate'
 
 import { executeTransaction } from './TransactionResolver'
@@ -146,7 +147,7 @@ export class TransactionLinkResolver {
       const transactionLink = await DbTransactionLink.findOneOrFail({ code }, { withDeleted: true })
       const user = await DbUser.findOneOrFail({ id: transactionLink.userId })
       let redeemedBy: User | null = null
-      if (transactionLink && transactionLink.redeemedBy) {
+      if (transactionLink?.redeemedBy) {
         redeemedBy = new User(await DbUser.findOneOrFail({ id: transactionLink.redeemedBy }))
       }
       return new TransactionLink(transactionLink, new User(user), redeemedBy)
@@ -266,6 +267,8 @@ export class TransactionLinkResolver {
           transaction.typeId = TransactionTypeId.CREATION
           transaction.memo = contribution.memo
           transaction.userId = contribution.userId
+          transaction.userGradidoID = user.gradidoID
+          transaction.userName = fullName(user.firstName, user.lastName)
           transaction.previous = lastTransaction ? lastTransaction.id : null
           transaction.amount = contribution.amount
           transaction.creationDate = contribution.contributionDate
diff --git a/backend/src/graphql/resolver/TransactionResolver.test.ts b/backend/src/graphql/resolver/TransactionResolver.test.ts
index 1a2f04838..96d434a29 100644
--- a/backend/src/graphql/resolver/TransactionResolver.test.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.test.ts
@@ -19,13 +19,17 @@ import {
   createContribution,
   login,
   sendCoins,
+  updateUserInfos,
 } from '@/seeds/graphql/mutations'
+import { transactionsQuery } from '@/seeds/graphql/queries'
 import { bobBaumeister } from '@/seeds/users/bob-baumeister'
 import { garrickOllivander } from '@/seeds/users/garrick-ollivander'
 import { peterLustig } from '@/seeds/users/peter-lustig'
 import { stephenHawking } from '@/seeds/users/stephen-hawking'
 
 let mutate: ApolloServerTestClient['mutate'], con: Connection
+let query: ApolloServerTestClient['query']
+
 let testEnv: {
   mutate: ApolloServerTestClient['mutate']
   query: ApolloServerTestClient['query']
@@ -35,6 +39,7 @@ let testEnv: {
 beforeAll(async () => {
   testEnv = await testEnvironment(logger)
   mutate = testEnv.mutate
+  query = testEnv.query
   con = testEnv.con
   await cleanDB()
 })
@@ -48,10 +53,13 @@ let bobData: any
 let peterData: any
 let user: User[]
 
+let bob: User
+let peter: User
+
 describe('send coins', () => {
   beforeAll(async () => {
-    await userFactory(testEnv, peterLustig)
-    await userFactory(testEnv, bobBaumeister)
+    peter = await userFactory(testEnv, peterLustig)
+    bob = await userFactory(testEnv, bobBaumeister)
     await userFactory(testEnv, stephenHawking)
     await userFactory(testEnv, garrickOllivander)
 
@@ -372,6 +380,114 @@ describe('send coins', () => {
       })
     })
 
+    describe('send coins via gradido ID', () => {
+      it('sends the coins', async () => {
+        await expect(
+          mutate({
+            mutation: sendCoins,
+            variables: {
+              identifier: peter?.gradidoID,
+              amount: 10,
+              memo: 'send via gradido ID',
+            },
+          }),
+        ).resolves.toMatchObject({
+          data: {
+            sendCoins: true,
+          },
+          errors: undefined,
+        })
+      })
+    })
+
+    describe('send coins via alias', () => {
+      beforeAll(async () => {
+        await mutate({
+          mutation: updateUserInfos,
+          variables: {
+            alias: 'bob',
+          },
+        })
+        await mutate({
+          mutation: login,
+          variables: peterData,
+        })
+      })
+
+      afterAll(async () => {
+        await mutate({
+          mutation: login,
+          variables: bobData,
+        })
+      })
+
+      it('sends the coins', async () => {
+        await expect(
+          mutate({
+            mutation: sendCoins,
+            variables: {
+              identifier: 'bob',
+              amount: 6.66,
+              memo: 'send via alias',
+            },
+          }),
+        ).resolves.toMatchObject({
+          data: {
+            sendCoins: true,
+          },
+          errors: undefined,
+        })
+      })
+
+      describe("peter's transactions", () => {
+        it('has all expected transactions', async () => {
+          await expect(query({ query: transactionsQuery })).resolves.toMatchObject({
+            data: {
+              transactionList: {
+                balance: expect.any(Object),
+                transactions: [
+                  expect.objectContaining({
+                    typeId: 'DECAY',
+                  }),
+                  expect.objectContaining({
+                    amount: expect.decimalEqual(-6.66),
+                    linkedUser: {
+                      firstName: 'Bob',
+                      gradidoID: bob?.gradidoID,
+                      lastName: 'der Baumeister',
+                    },
+                    memo: 'send via alias',
+                    typeId: 'SEND',
+                  }),
+                  expect.objectContaining({
+                    amount: expect.decimalEqual(10),
+                    linkedUser: {
+                      firstName: 'Bob',
+                      gradidoID: bob?.gradidoID,
+                      lastName: 'der Baumeister',
+                    },
+                    memo: 'send via gradido ID',
+                    typeId: 'RECEIVE',
+                  }),
+                  expect.objectContaining({
+                    amount: expect.decimalEqual(50),
+                    linkedUser: {
+                      firstName: 'Bob',
+                      gradidoID: bob?.gradidoID,
+                      lastName: 'der Baumeister',
+                    },
+                    memo: 'unrepeatable memo',
+                    typeId: 'RECEIVE',
+                  }),
+                ],
+              },
+            },
+            errors: undefined,
+          })
+        })
+      })
+    })
+
     describe('more transactions to test semaphore', () => {
       it('sends the coins four times in a row', async () => {
         await expect(
@@ -442,3 +558,42 @@ describe('send coins', () => {
     })
   })
 })
+
+describe('transactionList', () => {
+  describe('unauthenticated', () => {
+    it('throws an error', async () => {
+      await expect(query({ query: transactionsQuery })).resolves.toMatchObject({
+        errors: [new GraphQLError('401 Unauthorized')],
+      })
+    })
+  })
+
+  describe('authenticated', () => {
+    describe('no transactions', () => {
+      beforeAll(async () => {
+        await userFactory(testEnv, bobBaumeister)
+        await mutate({
+          mutation: login,
+          variables: {
+            email: 'bob@baumeister.de',
+            password: 'Aa12345_',
+          },
+        })
+      })
+
+      it('has no transactions and balance 0', async () => {
+        await expect(query({ query: transactionsQuery })).resolves.toMatchObject({
+          data: {
+            transactionList: {
+              balance: expect.objectContaining({
+                balance: expect.decimalEqual(0),
+              }),
+              transactions: [],
+            },
+          },
+          errors: undefined,
+        })
+      })
+    })
+  })
+})
diff --git a/backend/src/graphql/resolver/TransactionResolver.ts b/backend/src/graphql/resolver/TransactionResolver.ts
index bda108638..40e9ec2dd 100644
--- a/backend/src/graphql/resolver/TransactionResolver.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.ts
@@ -29,6 +29,7 @@ import { LogError } from '@/server/LogError'
 import { backendLogger as logger } from '@/server/logger'
 import { communityUser } from '@/util/communityUser'
 import { TRANSACTIONS_LOCK } from '@/util/TRANSACTIONS_LOCK'
+import { fullName } from '@/util/utilities'
 import { calculateBalance } from '@/util/validate'
 import { virtualLinkTransaction, virtualDecayTransaction } from '@/util/virtualTransactions'
 
@@ -48,9 +49,7 @@ export const executeTransaction = async (
   // acquire lock
   const releaseLock = await TRANSACTIONS_LOCK.acquire()
   try {
-    logger.info(
-      `executeTransaction(amount=${amount}, memo=${memo}, sender=${sender}, recipient=${recipient})...`,
-    )
+    logger.info('executeTransaction', amount, memo, sender, recipient)
 
     if (sender.id === recipient.id) {
       throw new LogError('Sender and Recipient are the same', sender.id)
@@ -87,7 +86,11 @@ export const executeTransaction = async (
       transactionSend.typeId = TransactionTypeId.SEND
       transactionSend.memo = memo
       transactionSend.userId = sender.id
+      transactionSend.userGradidoID = sender.gradidoID
+      transactionSend.userName = fullName(sender.firstName, sender.lastName)
       transactionSend.linkedUserId = recipient.id
+      transactionSend.linkedUserGradidoID = recipient.gradidoID
+      transactionSend.linkedUserName = fullName(recipient.firstName, recipient.lastName)
       transactionSend.amount = amount.mul(-1)
       transactionSend.balance = sendBalance.balance
       transactionSend.balanceDate = receivedCallDate
@@ -103,7 +106,11 @@ export const executeTransaction = async (
       transactionReceive.typeId = TransactionTypeId.RECEIVE
       transactionReceive.memo = memo
       transactionReceive.userId = recipient.id
+      transactionReceive.userGradidoID = recipient.gradidoID
+      transactionReceive.userName = fullName(recipient.firstName, recipient.lastName)
       transactionReceive.linkedUserId = sender.id
+      transactionReceive.linkedUserGradidoID = sender.gradidoID
+      transactionReceive.linkedUserName = fullName(sender.firstName, sender.lastName)
       transactionReceive.amount = amount
       const receiveBalance = await calculateBalance(recipient.id, amount, receivedCallDate)
       transactionReceive.balance = receiveBalance ? receiveBalance.balance : amount
@@ -119,10 +126,10 @@ export const executeTransaction = async (
       // Save linked transaction id for send
       transactionSend.linkedTransactionId = transactionReceive.id
       await queryRunner.manager.update(dbTransaction, { id: transactionSend.id }, transactionSend)
-      logger.debug(`send Transaction updated: ${transactionSend}`)
+      logger.debug('send Transaction updated', transactionSend)
 
       if (transactionLink) {
-        logger.info(`transactionLink: ${transactionLink}`)
+        logger.info('transactionLink', transactionLink)
         transactionLink.redeemedAt = receivedCallDate
         transactionLink.redeemedBy = recipient.id
         await queryRunner.manager.update(
@@ -271,8 +278,8 @@ export class TransactionResolver {
             sumAmount.mul(-1),
             sumHoldAvailableAmount.mul(-1),
             sumHoldAvailableAmount.minus(sumAmount.toString()).mul(-1),
-            firstDate || now,
-            lastDate || now,
+            firstDate ?? now,
+            lastDate ?? now,
             self,
             (userTransactions.length && userTransactions[0].balance) || new Decimal(0),
           ),
@@ -315,7 +322,6 @@ export class TransactionResolver {
       throw new LogError('Amount to send must be positive', amount)
     }
 
-    // TODO this is subject to replay attacks
     const senderUser = getUser(context)
 
     // validate recipient user
@@ -325,9 +331,7 @@ export class TransactionResolver {
     }
 
     await executeTransaction(amount, memo, senderUser, recipientUser)
-    logger.info(
-      `successful executeTransaction(amount=${amount}, memo=${memo}, senderUser=${senderUser}, recipientUser=${recipientUser})`,
-    )
+    logger.info('successful executeTransaction', amount, memo, senderUser, recipientUser)
     return true
   }
 }
diff --git a/backend/src/graphql/resolver/UserResolver.test.ts b/backend/src/graphql/resolver/UserResolver.test.ts
index d60ba7771..25787490f 100644
--- a/backend/src/graphql/resolver/UserResolver.test.ts
+++ b/backend/src/graphql/resolver/UserResolver.test.ts
@@ -20,6 +20,7 @@ import { ContributionLink } from '@model/ContributionLink'
 import { testEnvironment, headerPushMock, resetToken, cleanDB } from '@test/helpers'
 import { logger, i18n as localization } from '@test/testSetup'
 
+import { subscribe } from '@/apis/KlicktippController'
 import { CONFIG } from '@/config'
 import {
   sendAccountActivationEmail,
@@ -52,6 +53,7 @@ import {
   searchAdminUsers,
   searchUsers,
   user as userQuery,
+  checkUsername,
 } from '@/seeds/graphql/queries'
 import { bibiBloxberg } from '@/seeds/users/bibi-bloxberg'
 import { bobBaumeister } from '@/seeds/users/bob-baumeister'
@@ -61,8 +63,6 @@ import { stephenHawking } from '@/seeds/users/stephen-hawking'
 import { printTimeDuration } from '@/util/time'
 import { objectValuesToArray } from '@/util/utilities'
 
-// import { klicktippSignIn } from '@/apis/KlicktippController'
-
 jest.mock('@/emails/sendEmailVariants', () => {
   const originalModule = jest.requireActual('@/emails/sendEmailVariants')
   return {
@@ -76,15 +76,13 @@ jest.mock('@/emails/sendEmailVariants', () => {
   }
 })
 
-/*
-
 jest.mock('@/apis/KlicktippController', () => {
   return {
     __esModule: true,
-    klicktippSignIn: jest.fn(),
+    subscribe: jest.fn(),
+    getKlickTippUser: jest.fn(),
   }
 })
-*/
 
 let admin: User
 let user: User
@@ -556,16 +554,14 @@ describe('UserResolver', () => {
         expect(newUser.password.toString()).toEqual(encryptedPass.toString())
       })
 
-      /*
       it('calls the klicktipp API', () => {
-        expect(klicktippSignIn).toBeCalledWith(
-          user[0].email,
-          user[0].language,
-          user[0].firstName,
-          user[0].lastName,
+        expect(subscribe).toBeCalledWith(
+          newUser.emailContact.email,
+          newUser.language,
+          newUser.firstName,
+          newUser.lastName,
         )
       })
-      */
 
       it('returns true', () => {
         expect(result).toBeTruthy()
@@ -680,7 +676,6 @@ describe('UserResolver', () => {
           expect.objectContaining({
             data: {
               login: {
-                email: 'bibi@bloxberg.de',
                 firstName: 'Bibi',
                 hasElopage: false,
                 id: expect.any(Number),
@@ -953,7 +948,6 @@ describe('UserResolver', () => {
             expect.objectContaining({
               data: {
                 verifyLogin: {
-                  email: 'bibi@bloxberg.de',
                   firstName: 'Bibi',
                   lastName: 'Bloxberg',
                   language: 'de',
@@ -1205,6 +1199,28 @@ describe('UserResolver', () => {
         })
       })
 
+      describe('alias', () => {
+        beforeEach(() => {
+          jest.clearAllMocks()
+        })
+
+        describe('valid alias', () => {
+          it('updates the user in DB', async () => {
+            await mutate({
+              mutation: updateUserInfos,
+              variables: {
+                alias: 'bibi_Bloxberg',
+              },
+            })
+            await expect(User.findOne()).resolves.toEqual(
+              expect.objectContaining({
+                alias: 'bibi_Bloxberg',
+              }),
+            )
+          })
+        })
+      })
+
       describe('language is not valid', () => {
         it('throws an error', async () => {
           jest.clearAllMocks()
@@ -1310,7 +1326,7 @@ describe('UserResolver', () => {
               expect.objectContaining({
                 data: {
                   login: expect.objectContaining({
-                    email: 'bibi@bloxberg.de',
+                    firstName: 'Benjamin',
                   }),
                 },
               }),
@@ -1457,7 +1473,6 @@ describe('UserResolver', () => {
           expect.objectContaining({
             data: {
               login: {
-                email: 'bibi@bloxberg.de',
                 firstName: 'Bibi',
                 hasElopage: false,
                 id: expect.any(Number),
@@ -2343,15 +2358,21 @@ describe('UserResolver', () => {
           mutation: login,
           variables: { email: 'bibi@bloxberg.de', password: 'Aa12345_' },
         })
+        await mutate({
+          mutation: updateUserInfos,
+          variables: {
+            alias: 'bibi',
+          },
+        })
       })
 
-      describe('identifier is no gradido ID and no email', () => {
+      describe('identifier is no gradido ID, no email and no alias', () => {
         it('throws and logs "Unknown identifier type" error', async () => {
           await expect(
             query({
               query: userQuery,
               variables: {
-                identifier: 'identifier',
+                identifier: 'identifier_is_no_valid_alias!',
               },
             }),
           ).resolves.toEqual(
@@ -2359,7 +2380,10 @@ describe('UserResolver', () => {
               errors: [new GraphQLError('Unknown identifier type')],
             }),
           )
-          expect(logger.error).toBeCalledWith('Unknown identifier type', 'identifier')
+          expect(logger.error).toBeCalledWith(
+            'Unknown identifier type',
+            'identifier_is_no_valid_alias!',
+          )
         })
       })
 
@@ -2426,6 +2450,57 @@ describe('UserResolver', () => {
           )
         })
       })
+
+      describe('identifier is found via alias', () => {
+        it('returns user', async () => {
+          await expect(
+            query({
+              query: userQuery,
+              variables: {
+                identifier: 'bibi',
+              },
+            }),
+          ).resolves.toEqual(
+            expect.objectContaining({
+              data: {
+                user: {
+                  firstName: 'Bibi',
+                  lastName: 'Bloxberg',
+                },
+              },
+              errors: undefined,
+            }),
+          )
+        })
+      })
+    })
+  })
+
+  describe('check username', () => {
+    describe('reserved alias', () => {
+      it('returns false', async () => {
+        await expect(
+          query({ query: checkUsername, variables: { username: 'root' } }),
+        ).resolves.toMatchObject({
+          data: {
+            checkUsername: false,
+          },
+          errors: undefined,
+        })
+      })
+    })
+
+    describe('valid alias', () => {
+      it('returns true', async () => {
+        await expect(
+          query({ query: checkUsername, variables: { username: 'valid' } }),
+        ).resolves.toMatchObject({
+          data: {
+            checkUsername: true,
+          },
+          errors: undefined,
+        })
+      })
     })
   })
 })
diff --git a/backend/src/graphql/resolver/UserResolver.ts b/backend/src/graphql/resolver/UserResolver.ts
index 60b4403af..cbfd9b5c5 100644
--- a/backend/src/graphql/resolver/UserResolver.ts
+++ b/backend/src/graphql/resolver/UserResolver.ts
@@ -35,7 +35,7 @@ import { User } from '@model/User'
 import { UserAdmin, SearchUsersResult } from '@model/UserAdmin'
 import { UserRepository } from '@repository/User'
 
-import { klicktippSignIn } from '@/apis/KlicktippController'
+import { subscribe } from '@/apis/KlicktippController'
 import { encode } from '@/auth/JWT'
 import { RIGHTS } from '@/auth/RIGHTS'
 import { CONFIG } from '@/config'
@@ -73,6 +73,7 @@ import { getTimeDurationObject, printTimeDuration } from '@/util/time'
 import { FULL_CREATION_AVAILABLE } from './const/const'
 import { getUserCreations } from './util/creations'
 import { findUserByIdentifier } from './util/findUserByIdentifier'
+import { validateAlias } from './util/validateAlias'
 
 // eslint-disable-next-line @typescript-eslint/no-var-requires, import/no-commonjs
 const random = require('random-bigint')
@@ -94,7 +95,7 @@ const newEmailContact = (email: string, userId: number): DbUserContact => {
   emailContact.emailChecked = false
   emailContact.emailOptInTypeId = OptInType.EMAIL_OPT_IN_REGISTER
   emailContact.emailVerificationCode = random(64)
-  logger.debug(`newEmailContact...successful: ${emailContact}`)
+  logger.debug('newEmailContact...successful', emailContact)
   return emailContact
 }
 
@@ -130,7 +131,7 @@ export class UserResolver {
     // Elopage Status & Stored PublisherId
     user.hasElopage = await this.hasElopage(context)
 
-    logger.debug(`verifyLogin... successful: ${user.firstName}.${user.lastName}, ${user.email}`)
+    logger.debug(`verifyLogin... successful: ${user.firstName}.${user.lastName}`)
     return user
   }
 
@@ -185,7 +186,7 @@ export class UserResolver {
 
     context.setHeaders.push({
       key: 'token',
-      value: encode(dbUser.gradidoID),
+      value: await encode(dbUser.gradidoID),
     })
 
     await EVENT_USER_LOGIN(dbUser)
@@ -225,7 +226,7 @@ export class UserResolver {
     email = email.trim().toLowerCase()
     if (await checkEmailExists(email)) {
       const foundUser = await findUserByEmail(email)
-      logger.info(`DbUser.findOne(email=${email}) = ${foundUser}`)
+      logger.info('DbUser.findOne', email, foundUser)
 
       if (foundUser) {
         // ATTENTION: this logger-message will be exactly expected during tests, next line
@@ -238,7 +239,6 @@ export class UserResolver {
         const user = new User(communityDbUser)
         user.id = sodium.randombytes_random() % (2048 * 16) // TODO: for a better faking derive id from email so that it will be always the same id when the same email comes in?
         user.gradidoID = uuidv4()
-        user.email = email
         user.firstName = firstName
         user.lastName = lastName
         user.language = language
@@ -276,7 +276,7 @@ export class UserResolver {
     dbUser.firstName = firstName
     dbUser.lastName = lastName
     dbUser.language = language
-    dbUser.publisherId = publisherId || 0
+    dbUser.publisherId = publisherId ?? 0
     dbUser.passwordEncryptionType = PasswordEncryptionType.NO_PASSWORD
     logger.debug('new dbUser', dbUser)
     if (redeemCode) {
@@ -383,7 +383,7 @@ export class UserResolver {
       throw new LogError('Unable to save email verification code', user.emailContact)
     })
 
-    logger.info(`optInCode for ${email}=${user.emailContact}`)
+    logger.info('optInCode for', email, user.emailContact)
 
     void sendResetPasswordEmail({
       firstName: user.firstName,
@@ -469,9 +469,9 @@ export class UserResolver {
     // TODO do we always signUp the user? How to handle things with old users?
     if (userContact.emailOptInTypeId === OptInType.EMAIL_OPT_IN_REGISTER) {
       try {
-        await klicktippSignIn(userContact.email, user.language, user.firstName, user.lastName)
+        await subscribe(userContact.email, user.language, user.firstName, user.lastName)
         logger.debug(
-          `klicktippSignIn(${userContact.email}, ${user.language}, ${user.firstName}, ${user.lastName})`,
+          `subscribe(${userContact.email}, ${user.language}, ${user.firstName}, ${user.lastName})`,
         )
       } catch (e) {
         logger.error('Error subscribing to klicktipp', e)
@@ -487,7 +487,7 @@ export class UserResolver {
   async queryOptIn(@Arg('optIn') optIn: string): Promise<boolean> {
     logger.info(`queryOptIn(${optIn})...`)
     const userContact = await DbUserContact.findOneOrFail({ emailVerificationCode: optIn })
-    logger.debug(`found optInCode=${userContact}`)
+    logger.debug('found optInCode', userContact)
     // Code is only valid for `CONFIG.EMAIL_CODE_VALID_TIME` minutes
     if (!isEmailVerificationCodeValid(userContact.updatedAt || userContact.createdAt)) {
       throw new LogError(
@@ -498,6 +498,17 @@ export class UserResolver {
     return true
   }
 
+  @Authorized([RIGHTS.CHECK_USERNAME])
+  @Query(() => Boolean)
+  async checkUsername(@Arg('username') username: string): Promise<boolean> {
+    try {
+      await validateAlias(username)
+      return true
+    } catch {
+      return false
+    }
+  }
+
   @Authorized([RIGHTS.UPDATE_USER_INFOS])
   @Mutation(() => Boolean)
   async updateUserInfos(
@@ -505,6 +516,7 @@ export class UserResolver {
     {
       firstName,
       lastName,
+      alias,
       language,
       password,
       passwordNew,
@@ -524,6 +536,10 @@ export class UserResolver {
       user.lastName = lastName
     }
 
+    if (alias && (await validateAlias(alias))) {
+      user.alias = alias
+    }
+
     if (language) {
       if (!isLanguage(language)) {
         throw new LogError('Given language is not a valid language', language)
@@ -587,7 +603,7 @@ export class UserResolver {
     logger.info(`hasElopage()...`)
     const userEntity = getUser(context)
     const elopageBuys = hasElopageBuys(userEntity.emailContact.email)
-    logger.debug(`has ElopageBuys = ${elopageBuys}`)
+    logger.debug('has ElopageBuys', elopageBuys)
     return elopageBuys
   }
 
@@ -644,7 +660,7 @@ export class UserResolver {
         return 'user.' + fieldName
       }),
       searchText,
-      filters || null,
+      filters ?? null,
       currentPage,
       pageSize,
     )
@@ -710,14 +726,14 @@ export class UserResolver {
     // change isAdmin
     switch (user.isAdmin) {
       case null:
-        if (isAdmin === true) {
+        if (isAdmin) {
           user.isAdmin = new Date()
         } else {
           throw new LogError('User is already an usual user')
         }
         break
       default:
-        if (isAdmin === false) {
+        if (!isAdmin) {
           user.isAdmin = null
         } else {
           throw new LogError('User is already admin')
diff --git a/backend/src/graphql/resolver/util/creations.ts b/backend/src/graphql/resolver/util/creations.ts
index 1c0c0735e..d6f0e9af4 100644
--- a/backend/src/graphql/resolver/util/creations.ts
+++ b/backend/src/graphql/resolver/util/creations.ts
@@ -29,10 +29,12 @@ export const validateContribution = (
     throw new LogError('No information for available creations for the given date', creationDate)
   }
 
+  // eslint-disable-next-line security/detect-object-injection
   if (amount.greaterThan(creations[index].toString())) {
     throw new LogError(
       'The amount to be created exceeds the amount still available for this month',
       amount,
+      // eslint-disable-next-line security/detect-object-injection
       creations[index],
     )
   }
@@ -151,6 +153,7 @@ export const updateCreations = (
   if (index < 0) {
     throw new LogError('You cannot create GDD for a month older than the last three months')
   }
+  // eslint-disable-next-line security/detect-object-injection
   creations[index] = creations[index].plus(contribution.amount.toString())
   return creations
 }
@@ -169,6 +172,7 @@ export const getOpenCreations = async (
     return {
       month: date.getMonth(),
       year: date.getFullYear(),
+      // eslint-disable-next-line security/detect-object-injection
       amount: creations[index],
     }
   })
diff --git a/backend/src/graphql/resolver/util/eventList.ts b/backend/src/graphql/resolver/util/eventList.ts
new file mode 100644
index 000000000..45afe1832
--- /dev/null
+++ b/backend/src/graphql/resolver/util/eventList.ts
@@ -0,0 +1,17 @@
+import { Event as DbEvent } from '@entity/Event'
+import { User } from '@entity/User'
+import { UserContact } from '@entity/UserContact'
+
+export const lastDateTimeEvents = async (
+  eventType: string,
+): Promise<{ email: string; value: Date }[]> => {
+  return DbEvent.createQueryBuilder('event')
+    .select('MAX(event.created_at)', 'value')
+    .leftJoin(User, 'user', 'affected_user_id = user.id')
+    .leftJoin(UserContact, 'usercontact', 'user.id = usercontact.user_id')
+    .addSelect('usercontact.email', 'email')
+    .where('event.type = :eventType', { eventType })
+    .andWhere('usercontact.email IS NOT NULL')
+    .groupBy('event.affected_user_id')
+    .getRawMany()
+}
diff --git a/backend/src/graphql/resolver/util/findContributions.ts b/backend/src/graphql/resolver/util/findContributions.ts
index a08631e2c..28984d5b1 100644
--- a/backend/src/graphql/resolver/util/findContributions.ts
+++ b/backend/src/graphql/resolver/util/findContributions.ts
@@ -24,7 +24,7 @@ export const findContributions = async (
   }
   return DbContribution.findAndCount({
     where: {
-      ...(statusFilter && statusFilter.length && { contributionStatus: In(statusFilter) }),
+      ...(statusFilter?.length && { contributionStatus: In(statusFilter) }),
       ...(userId && { userId }),
     },
     withDeleted,
diff --git a/backend/src/graphql/resolver/util/findUserByIdentifier.ts b/backend/src/graphql/resolver/util/findUserByIdentifier.ts
index df932e544..bd9a25071 100644
--- a/backend/src/graphql/resolver/util/findUserByIdentifier.ts
+++ b/backend/src/graphql/resolver/util/findUserByIdentifier.ts
@@ -4,6 +4,8 @@ import { validate, version } from 'uuid'
 
 import { LogError } from '@/server/LogError'
 
+import { VALID_ALIAS_REGEX } from './validateAlias'
+
 export const findUserByIdentifier = async (identifier: string): Promise<DbUser> => {
   let user: DbUser | undefined
   if (validate(identifier) && version(identifier) === 4) {
@@ -27,8 +29,12 @@ export const findUserByIdentifier = async (identifier: string): Promise<DbUser>
     }
     user = userContact.user
     user.emailContact = userContact
+  } else if (VALID_ALIAS_REGEX.exec(identifier)) {
+    user = await DbUser.findOne({ where: { alias: identifier }, relations: ['emailContact'] })
+    if (!user) {
+      throw new LogError('No user found to given identifier', identifier)
+    }
   } else {
-    // last is alias when implemented
     throw new LogError('Unknown identifier type', identifier)
   }
 
diff --git a/backend/src/graphql/resolver/util/transactionLinkList.ts b/backend/src/graphql/resolver/util/transactionLinkList.ts
index 0dba5a400..ee79216c8 100644
--- a/backend/src/graphql/resolver/util/transactionLinkList.ts
+++ b/backend/src/graphql/resolver/util/transactionLinkList.ts
@@ -14,7 +14,7 @@ export async function transactionLinkList(
   filters: TransactionLinkFilters | null,
   user: DbUser,
 ): Promise<TransactionLinkResult> {
-  const { withDeleted, withExpired, withRedeemed } = filters || {
+  const { withDeleted, withExpired, withRedeemed } = filters ?? {
     withDeleted: false,
     withExpired: false,
     withRedeemed: false,
diff --git a/backend/src/graphql/resolver/util/validateAlias.test.ts b/backend/src/graphql/resolver/util/validateAlias.test.ts
new file mode 100644
index 000000000..0cb790edb
--- /dev/null
+++ b/backend/src/graphql/resolver/util/validateAlias.test.ts
@@ -0,0 +1,125 @@
+import { Connection } from '@dbTools/typeorm'
+import { User } from '@entity/User'
+import { ApolloServerTestClient } from 'apollo-server-testing'
+
+import { testEnvironment, cleanDB } from '@test/helpers'
+import { logger, i18n as localization } from '@test/testSetup'
+
+import { userFactory } from '@/seeds/factory/user'
+import { bibiBloxberg } from '@/seeds/users/bibi-bloxberg'
+
+import { validateAlias } from './validateAlias'
+
+let con: Connection
+let testEnv: {
+  mutate: ApolloServerTestClient['mutate']
+  query: ApolloServerTestClient['query']
+  con: Connection
+}
+
+beforeAll(async () => {
+  testEnv = await testEnvironment(logger, localization)
+  con = testEnv.con
+  await cleanDB()
+})
+
+afterAll(async () => {
+  await cleanDB()
+  await con.close()
+})
+
+describe('validate alias', () => {
+  beforeAll(() => {
+    jest.clearAllMocks()
+  })
+
+  describe('alias too short', () => {
+    it('throws and logs an error', async () => {
+      await expect(validateAlias('Bi')).rejects.toEqual(new Error('Given alias is too short'))
+      expect(logger.error).toBeCalledWith('Given alias is too short', 'Bi')
+    })
+  })
+
+  describe('alias too long', () => {
+    it('throws and logs an error', async () => {
+      await expect(validateAlias('BibiBloxbergHexHexHex')).rejects.toEqual(
+        new Error('Given alias is too long'),
+      )
+      expect(logger.error).toBeCalledWith('Given alias is too long', 'BibiBloxbergHexHexHex')
+    })
+  })
+
+  describe('alias contains invalid characters', () => {
+    it('throws and logs an error', async () => {
+      await expect(validateAlias('Bibi.Bloxberg')).rejects.toEqual(
+        new Error('Invalid characters in alias'),
+      )
+      expect(logger.error).toBeCalledWith('Invalid characters in alias', 'Bibi.Bloxberg')
+    })
+  })
+
+  describe('alias is a reserved word', () => {
+    it('throws and logs an error', async () => {
+      await expect(validateAlias('admin')).rejects.toEqual(new Error('Alias is not allowed'))
+      expect(logger.error).toBeCalledWith('Alias is not allowed', 'admin')
+    })
+  })
+
+  describe('alias is a reserved word with uppercase characters', () => {
+    it('throws and logs an error', async () => {
+      await expect(validateAlias('Admin')).rejects.toEqual(new Error('Alias is not allowed'))
+      expect(logger.error).toBeCalledWith('Alias is not allowed', 'Admin')
+    })
+  })
+
+  describe('hyphens and underscore', () => {
+    describe('alias starts with underscore', () => {
+      it('throws and logs an error', async () => {
+        await expect(validateAlias('_bibi')).rejects.toEqual(
+          new Error('Invalid characters in alias'),
+        )
+        expect(logger.error).toBeCalledWith('Invalid characters in alias', '_bibi')
+      })
+    })
+
+    describe('alias contains two following hyphens', () => {
+      it('throws and logs an error', async () => {
+        await expect(validateAlias('bi--bi')).rejects.toEqual(
+          new Error('Invalid characters in alias'),
+        )
+        expect(logger.error).toBeCalledWith('Invalid characters in alias', 'bi--bi')
+      })
+    })
+  })
+
+  describe('test against existing alias in database', () => {
+    beforeAll(async () => {
+      const bibi = await userFactory(testEnv, bibiBloxberg)
+      const user = await User.findOne({ id: bibi.id })
+      if (user) {
+        user.alias = 'b-b'
+        await user.save()
+      }
+    })
+
+    describe('alias exists in database', () => {
+      it('throws and logs an error', async () => {
+        await expect(validateAlias('b-b')).rejects.toEqual(new Error('Alias already in use'))
+        expect(logger.error).toBeCalledWith('Alias already in use', 'b-b')
+      })
+    })
+
+    describe('alias exists in database with in lower-case', () => {
+      it('throws and logs an error', async () => {
+        await expect(validateAlias('b-B')).rejects.toEqual(new Error('Alias already in use'))
+        expect(logger.error).toBeCalledWith('Alias already in use', 'b-B')
+      })
+    })
+
+    describe('valid alias', () => {
+      it('resolves to true', async () => {
+        await expect(validateAlias('bibi')).resolves.toEqual(true)
+      })
+    })
+  })
+})
diff --git a/backend/src/graphql/resolver/util/validateAlias.ts b/backend/src/graphql/resolver/util/validateAlias.ts
new file mode 100644
index 000000000..721733be4
--- /dev/null
+++ b/backend/src/graphql/resolver/util/validateAlias.ts
@@ -0,0 +1,40 @@
+import { Raw } from '@dbTools/typeorm'
+import { User as DbUser } from '@entity/User'
+
+import { LogError } from '@/server/LogError'
+
+// eslint-disable-next-line security/detect-unsafe-regex
+export const VALID_ALIAS_REGEX = /^(?=.{3,20}$)[a-zA-Z0-9]+(?:[_-][a-zA-Z0-9]+?)*$/
+
+const RESERVED_ALIAS = [
+  'admin',
+  'email',
+  'gast',
+  'gdd',
+  'gradido',
+  'guest',
+  'home',
+  'root',
+  'support',
+  'temp',
+  'tmp',
+  'tmp',
+  'user',
+  'usr',
+  'var',
+]
+
+export const validateAlias = async (alias: string): Promise<boolean> => {
+  if (alias.length < 3) throw new LogError('Given alias is too short', alias)
+  if (alias.length > 20) throw new LogError('Given alias is too long', alias)
+  if (!alias.match(VALID_ALIAS_REGEX)) throw new LogError('Invalid characters in alias', alias)
+  if (RESERVED_ALIAS.includes(alias.toLowerCase()))
+    throw new LogError('Alias is not allowed', alias)
+  const aliasInUse = await DbUser.find({
+    where: { alias: Raw((a) => `LOWER(${a}) = "${alias.toLowerCase()}"`) },
+  })
+  if (aliasInUse.length !== 0) {
+    throw new LogError('Alias already in use', alias)
+  }
+  return true
+}
diff --git a/backend/src/index.ts b/backend/src/index.ts
index 86f78326d..6e0191155 100644
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -13,7 +13,7 @@ async function main() {
       console.log(`GraphIQL available at http://localhost:${CONFIG.PORT}`)
     }
   })
-  void startValidateCommunities(Number(CONFIG.FEDERATION_VALIDATE_COMMUNITY_TIMER))
+  startValidateCommunities(Number(CONFIG.FEDERATION_VALIDATE_COMMUNITY_TIMER))
 }
 
 main().catch((e) => {
diff --git a/backend/src/middleware/klicktippMiddleware.ts b/backend/src/middleware/klicktippMiddleware.ts
index 4c5f8db4f..038bd3dd3 100644
--- a/backend/src/middleware/klicktippMiddleware.ts
+++ b/backend/src/middleware/klicktippMiddleware.ts
@@ -10,19 +10,6 @@ import { KlickTipp } from '@model/KlickTipp'
 import { getKlickTippUser } from '@/apis/KlicktippController'
 import { klickTippLogger as logger } from '@/server/logger'
 
-// export const klicktippRegistrationMiddleware: MiddlewareFn = async (
-//   // Only for demo
-//   /* eslint-disable-next-line @typescript-eslint/no-unused-vars */
-//   { root, args, context, info },
-//   next,
-// ) => {
-//   // Do Something here before resolver is called
-//   const result = await next()
-//   // Do Something here after resolver is completed
-//   await klicktippSignIn(result.email, result.language, result.firstName, result.lastName)
-//   return result
-// }
-
 export const klicktippNewsletterStateMiddleware: MiddlewareFn = async (
   /* eslint-disable-next-line @typescript-eslint/no-unused-vars */
   { root, args, context, info },
diff --git a/backend/src/seeds/graphql/mutations.ts b/backend/src/seeds/graphql/mutations.ts
index 67a01977f..22e0b1b09 100644
--- a/backend/src/seeds/graphql/mutations.ts
+++ b/backend/src/seeds/graphql/mutations.ts
@@ -28,6 +28,7 @@ export const updateUserInfos = gql`
   mutation (
     $firstName: String
     $lastName: String
+    $alias: String
     $password: String
     $passwordNew: String
     $locale: String
@@ -37,6 +38,7 @@ export const updateUserInfos = gql`
     updateUserInfos(
       firstName: $firstName
       lastName: $lastName
+      alias: $alias
       password: $password
       passwordNew: $passwordNew
       language: $locale
@@ -305,7 +307,6 @@ export const login = gql`
   mutation ($email: String!, $password: String!, $publisherId: Int) {
     login(email: $email, password: $password, publisherId: $publisherId) {
       id
-      email
       firstName
       lastName
       language
diff --git a/backend/src/seeds/graphql/queries.ts b/backend/src/seeds/graphql/queries.ts
index 8da5211a4..ce7efbfc3 100644
--- a/backend/src/seeds/graphql/queries.ts
+++ b/backend/src/seeds/graphql/queries.ts
@@ -3,7 +3,6 @@ import { gql } from 'graphql-tag'
 export const verifyLogin = gql`
   query {
     verifyLogin {
-      email
       firstName
       lastName
       language
@@ -23,32 +22,33 @@ export const queryOptIn = gql`
   }
 `
 
+export const checkUsername = gql`
+  query ($username: String!) {
+    checkUsername(username: $username)
+  }
+`
+
 export const transactionsQuery = gql`
-  query (
-    $currentPage: Int = 1
-    $pageSize: Int = 25
-    $order: Order = DESC
-    $onlyCreations: Boolean = false
-  ) {
-    transactionList(
-      currentPage: $currentPage
-      pageSize: $pageSize
-      order: $order
-      onlyCreations: $onlyCreations
-    ) {
-      balanceGDT
-      count
-      balance
+  query ($currentPage: Int = 1, $pageSize: Int = 25, $order: Order = DESC) {
+    transactionList(currentPage: $currentPage, pageSize: $pageSize, order: $order) {
+      balance {
+        balance
+        balanceGDT
+        count
+        linkCount
+      }
       transactions {
         id
         typeId
         amount
         balance
+        previousBalance
         balanceDate
         memo
         linkedUser {
           firstName
           lastName
+          gradidoID
         }
         decay {
           decay
@@ -56,6 +56,7 @@ export const transactionsQuery = gql`
           end
           duration
         }
+        linkId
       }
     }
   }
diff --git a/backend/src/seeds/index.ts b/backend/src/seeds/index.ts
index c2533765e..77fa51990 100644
--- a/backend/src/seeds/index.ts
+++ b/backend/src/seeds/index.ts
@@ -31,8 +31,8 @@ const context = {
 
 export const cleanDB = async () => {
   // this only works as long we do not have foreign key constraints
-  for (let i = 0; i < entities.length; i++) {
-    await resetEntity(entities[i])
+  for (const entity of entities) {
+    await resetEntity(entity)
   }
 }
 
@@ -54,9 +54,8 @@ const run = async () => {
   logger.info('##seed## clean database successful...')
 
   // seed the standard users
-  for (let i = 0; i < users.length; i++) {
-    const dbUser = await userFactory(seedClient, users[i])
-    logger.info(`##seed## seed standard users[ ${i} ]= ${JSON.stringify(dbUser, null, 2)}`)
+  for (const user of users) {
+    await userFactory(seedClient, user)
   }
   logger.info('##seed## seeding all standard users successful...')
 
@@ -73,20 +72,20 @@ const run = async () => {
   logger.info('##seed## seeding all random users successful...')
 
   // create GDD
-  for (let i = 0; i < creations.length; i++) {
-    await creationFactory(seedClient, creations[i])
+  for (const creation of creations) {
+    await creationFactory(seedClient, creation)
   }
   logger.info('##seed## seeding all creations successful...')
 
   // create Transaction Links
-  for (let i = 0; i < transactionLinks.length; i++) {
-    await transactionLinkFactory(seedClient, transactionLinks[i])
+  for (const transactionLink of transactionLinks) {
+    await transactionLinkFactory(seedClient, transactionLink)
   }
   logger.info('##seed## seeding all transactionLinks successful...')
 
   // create Contribution Links
-  for (let i = 0; i < contributionLinks.length; i++) {
-    await contributionLinkFactory(seedClient, contributionLinks[i])
+  for (const contributionLink of contributionLinks) {
+    await contributionLinkFactory(seedClient, contributionLink)
   }
   logger.info('##seed## seeding all contributionLinks successful...')
 
diff --git a/backend/src/server/createServer.ts b/backend/src/server/createServer.ts
index 777d6dfbe..c162d9f6f 100644
--- a/backend/src/server/createServer.ts
+++ b/backend/src/server/createServer.ts
@@ -1,14 +1,14 @@
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
 /* eslint-disable @typescript-eslint/restrict-template-expressions */
 /* eslint-disable @typescript-eslint/unbound-method */
-import { Connection } from '@dbTools/typeorm'
+import { Connection as DbConnection } from '@dbTools/typeorm'
 import { ApolloServer } from 'apollo-server-express'
 import express, { Express, json, urlencoded } from 'express'
 import { Logger } from 'log4js'
 
 import { CONFIG } from '@/config'
 import { schema } from '@/graphql/schema'
-import { connection } from '@/typeorm/connection'
+import { Connection } from '@/typeorm/connection'
 import { checkDBVersion } from '@/typeorm/DBVersion'
 import { elopageWebhook } from '@/webhook/elopage'
 
@@ -21,7 +21,11 @@ import { plugins } from './plugins'
 // TODO implement
 // import queryComplexity, { simpleEstimator, fieldConfigEstimator } from "graphql-query-complexity";
 
-type ServerDef = { apollo: ApolloServer; app: Express; con: Connection }
+interface ServerDef {
+  apollo: ApolloServer
+  app: Express
+  con: DbConnection
+}
 
 export const createServer = async (
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
@@ -33,8 +37,8 @@ export const createServer = async (
   logger.debug('createServer...')
 
   // open mysql connection
-  const con = await connection()
-  if (!con || !con.isConnected) {
+  const con = await Connection.getInstance()
+  if (!con?.isConnected) {
     logger.fatal(`Couldn't open connection to database!`)
     throw new Error(`Fatal: Couldn't open connection to database`)
   }
diff --git a/backend/src/server/logger.ts b/backend/src/server/logger.ts
index d1edbd8fb..0f146b7f7 100644
--- a/backend/src/server/logger.ts
+++ b/backend/src/server/logger.ts
@@ -7,6 +7,7 @@ import { configure, getLogger } from 'log4js'
 
 import { CONFIG } from '@/config'
 
+// eslint-disable-next-line security/detect-non-literal-fs-filename
 const options = JSON.parse(readFileSync(CONFIG.LOG4JS_CONFIG, 'utf-8'))
 
 options.categories.backend.level = CONFIG.LOG_LEVEL
diff --git a/backend/src/server/plugins.ts b/backend/src/server/plugins.ts
index 1da062b83..3e0fc50e1 100644
--- a/backend/src/server/plugins.ts
+++ b/backend/src/server/plugins.ts
@@ -12,7 +12,7 @@ const setHeadersPlugin = {
     return {
       willSendResponse(requestContext: any) {
         const { setHeaders = [] } = requestContext.context
-        setHeaders.forEach(({ key, value }: { [key: string]: string }) => {
+        setHeaders.forEach(({ key, value }: Record<string, string>) => {
           if (requestContext.response.http.headers.get(key)) {
             requestContext.response.http.headers.set(key, value)
           } else {
@@ -27,8 +27,8 @@ const setHeadersPlugin = {
 
 const filterVariables = (variables: any) => {
   const vars = clonedeep(variables)
-  if (vars && vars.password) vars.password = '***'
-  if (vars && vars.passwordNew) vars.passwordNew = '***'
+  if (vars?.password) vars.password = '***'
+  if (vars?.passwordNew) vars.passwordNew = '***'
   return vars
 }
 
diff --git a/backend/src/typeorm/DBVersion.ts b/backend/src/typeorm/DBVersion.ts
index c4c8d6c78..f465069d3 100644
--- a/backend/src/typeorm/DBVersion.ts
+++ b/backend/src/typeorm/DBVersion.ts
@@ -14,10 +14,10 @@ const getDBVersion = async (): Promise<string | null> => {
 
 const checkDBVersion = async (DB_VERSION: string): Promise<boolean> => {
   const dbVersion = await getDBVersion()
-  if (!dbVersion || dbVersion.indexOf(DB_VERSION) === -1) {
+  if (!dbVersion?.includes(DB_VERSION)) {
     logger.error(
       `Wrong database version detected - the backend requires '${DB_VERSION}' but found '${
-        dbVersion || 'None'
+        dbVersion ?? 'None'
       }`,
     )
     return false
diff --git a/backend/src/typeorm/connection.ts b/backend/src/typeorm/connection.ts
index 7dec820b5..3c8307478 100644
--- a/backend/src/typeorm/connection.ts
+++ b/backend/src/typeorm/connection.ts
@@ -1,33 +1,55 @@
 // TODO This is super weird - since the entities are defined in another project they have their own globals.
 //      We cannot use our connection here, but must use the external typeorm installation
-import { Connection, createConnection, FileLogger } from '@dbTools/typeorm'
+import { Connection as DbConnection, createConnection, FileLogger } from '@dbTools/typeorm'
 import { entities } from '@entity/index'
 
 import { CONFIG } from '@/config'
 
-export const connection = async (): Promise<Connection | null> => {
-  try {
-    return createConnection({
-      name: 'default',
-      type: 'mysql',
-      host: CONFIG.DB_HOST,
-      port: CONFIG.DB_PORT,
-      username: CONFIG.DB_USER,
-      password: CONFIG.DB_PASSWORD,
-      database: CONFIG.DB_DATABASE,
-      entities,
-      synchronize: false,
-      logging: true,
-      logger: new FileLogger('all', {
-        logPath: CONFIG.TYPEORM_LOGGING_RELATIVE_PATH,
-      }),
-      extra: {
-        charset: 'utf8mb4_unicode_ci',
-      },
-    })
-  } catch (error) {
-    // eslint-disable-next-line no-console
-    console.log(error)
-    return null
+// eslint-disable-next-line @typescript-eslint/no-extraneous-class
+export class Connection {
+  private static instance: DbConnection
+
+  /**
+   * The Singleton's constructor should always be private to prevent direct
+   * construction calls with the `new` operator.
+   */
+  // eslint-disable-next-line no-useless-constructor, @typescript-eslint/no-empty-function
+  private constructor() {}
+
+  /**
+   * The static method that controls the access to the singleton instance.
+   *
+   * This implementation let you subclass the Singleton class while keeping
+   * just one instance of each subclass around.
+   */
+  public static async getInstance(): Promise<DbConnection | null> {
+    if (Connection.instance) {
+      return Connection.instance
+    }
+    try {
+      Connection.instance = await createConnection({
+        name: 'default',
+        type: 'mysql',
+        host: CONFIG.DB_HOST,
+        port: CONFIG.DB_PORT,
+        username: CONFIG.DB_USER,
+        password: CONFIG.DB_PASSWORD,
+        database: CONFIG.DB_DATABASE,
+        entities,
+        synchronize: false,
+        logging: true,
+        logger: new FileLogger('all', {
+          logPath: CONFIG.TYPEORM_LOGGING_RELATIVE_PATH,
+        }),
+        extra: {
+          charset: 'utf8mb4_unicode_ci',
+        },
+      })
+      return Connection.instance
+    } catch (error) {
+      // eslint-disable-next-line no-console
+      console.log(error)
+      return null
+    }
   }
 }
diff --git a/backend/src/util/executeKlicktipp.ts b/backend/src/util/executeKlicktipp.ts
new file mode 100644
index 000000000..74b453307
--- /dev/null
+++ b/backend/src/util/executeKlicktipp.ts
@@ -0,0 +1,16 @@
+import { Connection } from '@/typeorm/connection'
+
+import { exportEventDataToKlickTipp } from './klicktipp'
+
+async function executeKlicktipp(): Promise<boolean> {
+  const connection = await Connection.getInstance()
+  if (connection) {
+    await exportEventDataToKlickTipp()
+    await connection.close()
+    return true
+  } else {
+    return false
+  }
+}
+
+void executeKlicktipp()
diff --git a/backend/src/util/klicktipp.test.ts b/backend/src/util/klicktipp.test.ts
new file mode 100644
index 000000000..6639a0aa4
--- /dev/null
+++ b/backend/src/util/klicktipp.test.ts
@@ -0,0 +1,65 @@
+/* eslint-disable @typescript-eslint/no-unsafe-return */
+/* eslint-disable @typescript-eslint/no-unsafe-call */
+/* eslint-disable @typescript-eslint/no-unsafe-member-access */
+/* eslint-disable @typescript-eslint/no-unsafe-assignment */
+import { Connection } from '@dbTools/typeorm'
+import { Event as DbEvent } from '@entity/Event'
+import { ApolloServerTestClient } from 'apollo-server-testing'
+
+import { testEnvironment, cleanDB, resetToken } from '@test/helpers'
+
+import { addFieldsToSubscriber } from '@/apis/KlicktippController'
+import { creations } from '@/seeds/creation'
+import { creationFactory } from '@/seeds/factory/creation'
+import { userFactory } from '@/seeds/factory/user'
+import { login } from '@/seeds/graphql/mutations'
+import { bibiBloxberg } from '@/seeds/users/bibi-bloxberg'
+import { peterLustig } from '@/seeds/users/peter-lustig'
+
+import { exportEventDataToKlickTipp } from './klicktipp'
+
+jest.mock('@/apis/KlicktippController')
+
+let mutate: ApolloServerTestClient['mutate'], con: Connection
+let testEnv: {
+  mutate: ApolloServerTestClient['mutate']
+  query: ApolloServerTestClient['query']
+  con: Connection
+}
+
+beforeAll(async () => {
+  testEnv = await testEnvironment()
+  mutate = testEnv.mutate
+  con = testEnv.con
+  await DbEvent.clear()
+})
+
+afterAll(async () => {
+  await cleanDB()
+  await con.close()
+})
+
+describe('klicktipp', () => {
+  beforeAll(async () => {
+    await userFactory(testEnv, bibiBloxberg)
+    await userFactory(testEnv, peterLustig)
+    const bibisCreation = creations.find((creation) => creation.email === 'bibi@bloxberg.de')
+    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+    await creationFactory(testEnv, bibisCreation!)
+    await mutate({
+      mutation: login,
+      variables: { email: 'bibi@bloxberg.de', password: 'Aa12345_' },
+    })
+  })
+
+  afterAll(() => {
+    resetToken()
+  })
+
+  describe('exportEventDataToKlickTipp', () => {
+    it('calls the KlicktippController', async () => {
+      await exportEventDataToKlickTipp()
+      expect(addFieldsToSubscriber).toBeCalled()
+    })
+  })
+})
diff --git a/backend/src/util/klicktipp.ts b/backend/src/util/klicktipp.ts
index e34a9c384..c07b3128a 100644
--- a/backend/src/util/klicktipp.ts
+++ b/backend/src/util/klicktipp.ts
@@ -1,18 +1,14 @@
+// eslint-disable @typescript-eslint/no-explicit-any
 import { User } from '@entity/User'
 
-import { getKlickTippUser } from '@/apis/KlicktippController'
-import { LogError } from '@/server/LogError'
-import { connection } from '@/typeorm/connection'
+import { getKlickTippUser, addFieldsToSubscriber } from '@/apis/KlicktippController'
+import { EventType } from '@/event/EventType'
+import { lastDateTimeEvents } from '@/graphql/resolver/util/eventList'
 
 export async function retrieveNotRegisteredEmails(): Promise<string[]> {
-  const con = await connection()
-  if (!con) {
-    throw new LogError('No connection to database')
-  }
   const users = await User.find({ relations: ['emailContact'] })
   const notRegisteredUser = []
-  for (let i = 0; i < users.length; i++) {
-    const user = users[i]
+  for (const user of users) {
     try {
       await getKlickTippUser(user.emailContact.email)
     } catch (err) {
@@ -21,10 +17,39 @@ export async function retrieveNotRegisteredEmails(): Promise<string[]> {
       console.log(`${user.emailContact.email}`)
     }
   }
-  await con.close()
   // eslint-disable-next-line no-console
   console.log('User die nicht bei KlickTipp vorhanden sind: ', notRegisteredUser)
   return notRegisteredUser
 }
 
-void retrieveNotRegisteredEmails()
+async function klickTippSendFieldToUser(
+  events: { email: string; value: Date }[],
+  field: string,
+): Promise<void> {
+  for (const event of events) {
+    const time = event.value.setSeconds(0)
+    await addFieldsToSubscriber(event.email, { [field]: Math.trunc(time / 1000) })
+  }
+}
+
+export async function exportEventDataToKlickTipp(): Promise<boolean> {
+  const lastLoginEvents = await lastDateTimeEvents(EventType.USER_LOGIN)
+  await klickTippSendFieldToUser(lastLoginEvents, 'field186060')
+
+  const registeredEvents = await lastDateTimeEvents(EventType.USER_ACTIVATE_ACCOUNT)
+  await klickTippSendFieldToUser(registeredEvents, 'field186061')
+
+  const receiveTransactionEvents = await lastDateTimeEvents(EventType.TRANSACTION_RECEIVE)
+  await klickTippSendFieldToUser(receiveTransactionEvents, 'field185674')
+
+  const contributionCreateEvents = await lastDateTimeEvents(EventType.TRANSACTION_SEND)
+  await klickTippSendFieldToUser(contributionCreateEvents, 'field185673')
+
+  const linkRedeemedEvents = await lastDateTimeEvents(EventType.TRANSACTION_LINK_REDEEM)
+  await klickTippSendFieldToUser(linkRedeemedEvents, 'field185676')
+
+  const confirmContributionEvents = await lastDateTimeEvents(EventType.ADMIN_CONTRIBUTION_CONFIRM)
+  await klickTippSendFieldToUser(confirmContributionEvents, 'field185675')
+
+  return true
+}
diff --git a/backend/src/util/utilities.ts b/backend/src/util/utilities.ts
index 2cf53f1e4..904c86226 100644
--- a/backend/src/util/utilities.ts
+++ b/backend/src/util/utilities.ts
@@ -1,11 +1,9 @@
 import { Decimal } from 'decimal.js-light'
 import i18n from 'i18n'
 
-export const objectValuesToArray = (obj: { [x: string]: string }): Array<string> => {
-  return Object.keys(obj).map(function (key) {
-    return obj[key]
-  })
-}
+export const objectValuesToArray = (obj: Record<string, string>): string[] =>
+  // eslint-disable-next-line security/detect-object-injection
+  Object.keys(obj).map((key) => obj[key])
 
 export const decimalSeparatorByLanguage = (a: Decimal, language: string): string => {
   const rememberLocaleToRestore = i18n.getLocale()
@@ -14,3 +12,6 @@ export const decimalSeparatorByLanguage = (a: Decimal, language: string): string
   i18n.setLocale(rememberLocaleToRestore)
   return result
 }
+
+export const fullName = (firstName: string, lastName: string): string =>
+  [firstName, lastName].filter(Boolean).join(' ')
diff --git a/backend/src/util/virtualTransactions.ts b/backend/src/util/virtualTransactions.ts
index 5d1fbbfd3..a10e566d1 100644
--- a/backend/src/util/virtualTransactions.ts
+++ b/backend/src/util/virtualTransactions.ts
@@ -54,6 +54,10 @@ const virtualLinkTransaction = (
     creationDate: null,
     contribution: null,
     ...defaultModelFunctions,
+    userGradidoID: '',
+    userName: null,
+    linkedUserGradidoID: null,
+    linkedUserName: null,
   }
   return new Transaction(linkDbTransaction, user)
 }
@@ -84,6 +88,10 @@ const virtualDecayTransaction = (
     creationDate: null,
     contribution: null,
     ...defaultModelFunctions,
+    userGradidoID: '',
+    userName: null,
+    linkedUserGradidoID: null,
+    linkedUserName: null,
   }
   return new Transaction(decayDbTransaction, user)
 }
diff --git a/backend/src/webhook/elopage.ts b/backend/src/webhook/elopage.ts
index f386b6e99..07e7d4ecf 100644
--- a/backend/src/webhook/elopage.ts
+++ b/backend/src/webhook/elopage.ts
@@ -115,6 +115,7 @@ export const elopageWebhook = async (req: any, res: any): Promise<void> => {
   ) {
     const email = loginElopageBuy.payerEmail
 
+    // eslint-disable-next-line security/detect-unsafe-regex
     const VALIDATE_EMAIL = /^[a-zA-Z0-9.!#$%&?*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/
     const VALIDATE_NAME = /^<>&;]{2,}$/
 
@@ -146,7 +147,7 @@ export const elopageWebhook = async (req: any, res: any): Promise<void> => {
         email,
         firstName,
         lastName,
-        publisherId: loginElopageBuy.publisherId || 0, // This seemed to be the default value if not set
+        publisherId: loginElopageBuy.publisherId ?? 0, // This seemed to be the default value if not set
       })
     } catch (error) {
       // eslint-disable-next-line no-console
diff --git a/backend/test/helpers.ts b/backend/test/helpers.ts
index d42db959f..7f55b3c70 100644
--- a/backend/test/helpers.ts
+++ b/backend/test/helpers.ts
@@ -22,8 +22,8 @@ const context = {
 
 export const cleanDB = async () => {
   // this only works as lond we do not have foreign key constraints
-  for (let i = 0; i < entities.length; i++) {
-    await resetEntity(entities[i])
+  for (const entity of entities) {
+    await resetEntity(entity)
   }
 }
 
diff --git a/backend/yarn.lock b/backend/yarn.lock
index 1bc8c64fd..4d070934b 100644
--- a/backend/yarn.lock
+++ b/backend/yarn.lock
@@ -382,6 +382,14 @@
   dependencies:
     "@cspotcode/source-map-consumer" "0.8.0"
 
+"@eslint-community/eslint-plugin-eslint-comments@^3.2.1":
+  version "3.2.1"
+  resolved "https://registry.yarnpkg.com/@eslint-community/eslint-plugin-eslint-comments/-/eslint-plugin-eslint-comments-3.2.1.tgz#3c65061e27f155eae3744c3b30c5a8253a959040"
+  integrity sha512-/HZbjIGaVO2zLlWX3gRgiHmKRVvvqrC0zVu3eXnIj1ORxoyfGSj50l0PfDfqihyZAqrDYzSMdJesXzFjvAoiLQ==
+  dependencies:
+    escape-string-regexp "^1.0.5"
+    ignore "^5.2.4"
+
 "@eslint-community/eslint-utils@^4.2.0":
   version "4.2.0"
   resolved "https://registry.yarnpkg.com/@eslint-community/eslint-utils/-/eslint-utils-4.2.0.tgz#a831e6e468b4b2b5ae42bf658bea015bf10bc518"
@@ -1051,13 +1059,6 @@
   resolved "https://registry.yarnpkg.com/@types/json5/-/json5-0.0.29.tgz#ee28707ae94e11d2b827bcbe5270bcea7f3e71ee"
   integrity sha1-7ihweulOEdK4J7y+UnC86n8+ce4=
 
-"@types/jsonwebtoken@^8.5.2":
-  version "8.5.5"
-  resolved "https://registry.yarnpkg.com/@types/jsonwebtoken/-/jsonwebtoken-8.5.5.tgz#da5f2f4baee88f052ef3e4db4c1a0afb46cff22c"
-  integrity sha512-OGqtHQ7N5/Ap/TUwO6IgHDuLiAoTmHhGpNvgkCm/F4N6pKzx/RBSfr2OXZSwC6vkfnsEdb6+7DNZVtiXiwdwFw==
-  dependencies:
-    "@types/node" "*"
-
 "@types/keygrip@*":
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/@types/keygrip/-/keygrip-1.0.2.tgz#513abfd256d7ad0bf1ee1873606317b33b1b2a72"
@@ -1994,11 +1995,6 @@ bser@2.1.1:
   dependencies:
     node-int64 "^0.4.0"
 
-buffer-equal-constant-time@1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/buffer-equal-constant-time/-/buffer-equal-constant-time-1.0.1.tgz#f8e71132f7ffe6e01a5c9697a4c6f3e48d5cc819"
-  integrity sha1-+OcRMvf/5uAaXJaXpMbz5I1cyBk=
-
 buffer-from@^1.0.0:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/buffer-from/-/buffer-from-1.1.2.tgz#2b146a6fd72e80b4f55d255f35ed59a3a9a41bd5"
@@ -2691,13 +2687,6 @@ duplexer3@^0.1.4:
   resolved "https://registry.yarnpkg.com/duplexer3/-/duplexer3-0.1.4.tgz#ee01dd1cac0ed3cbc7fdbea37dc0a8f1ce002ce2"
   integrity sha1-7gHdHKwO08vH/b6jfcCo8c4ALOI=
 
-ecdsa-sig-formatter@1.0.11:
-  version "1.0.11"
-  resolved "https://registry.yarnpkg.com/ecdsa-sig-formatter/-/ecdsa-sig-formatter-1.0.11.tgz#ae0f0fa2d85045ef14a817daa3ce9acd0489e5bf"
-  integrity sha512-nagl3RYrbNv6kQkeJIpt6NJZy8twLB/2vtz6yN9Z4vRKHN4/QZJIEbqohALSgwKdnksuY3k5Addp5lg8sVoVcQ==
-  dependencies:
-    safe-buffer "^5.0.1"
-
 ee-first@1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/ee-first/-/ee-first-1.1.1.tgz#590c61156b0ae2f4f0255732a158b266bc56b21d"
@@ -3005,6 +2994,13 @@ eslint-plugin-promise@^6.1.1:
   resolved "https://registry.yarnpkg.com/eslint-plugin-promise/-/eslint-plugin-promise-6.1.1.tgz#269a3e2772f62875661220631bd4dafcb4083816"
   integrity sha512-tjqWDwVZQo7UIPMeDReOpUgHCmCiH+ePnVT+5zVapL0uuHnegBUs2smM13CzOs2Xb5+MHMRFTs9v24yjba4Oig==
 
+eslint-plugin-security@^1.7.1:
+  version "1.7.1"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-security/-/eslint-plugin-security-1.7.1.tgz#0e9c4a471f6e4d3ca16413c7a4a51f3966ba16e4"
+  integrity sha512-sMStceig8AFglhhT2LqlU5r+/fn9OwsA72O5bBuQVTssPCdQAOQzL+oMn/ZcpeUY6KcNfLJArgcrsSULNjYYdQ==
+  dependencies:
+    safe-regex "^2.1.1"
+
 eslint-plugin-type-graphql@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/eslint-plugin-type-graphql/-/eslint-plugin-type-graphql-1.0.0.tgz#d348560ed628d6ca1dfcea35a02891432daafe6b"
@@ -3649,7 +3645,7 @@ graceful-fs@^4.1.6, graceful-fs@^4.2.0:
   integrity sha512-9ByhssR2fPVsNZj478qUUbKfmL0+t5BDVyjShtyZZLiK7ZDAArFFfopyOTj0M05wE2tJPisA4iTnnXl2YoPvOA==
 
 "gradido-database@file:../database":
-  version "1.19.1"
+  version "1.20.0"
   dependencies:
     "@types/uuid" "^8.3.4"
     cross-env "^7.0.3"
@@ -3977,7 +3973,7 @@ ignore@^5.1.1:
   resolved "https://registry.yarnpkg.com/ignore/-/ignore-5.1.8.tgz#f150a8b50a34289b33e22f5889abd4d8016f0e57"
   integrity sha512-BMpfD7PpiETpBl/A6S498BaIJ6Y/ABT93ETbby2fP00v4EbvPBXWEoaR1UBPKs3iR53pJY7EtZk5KACI57i1Uw==
 
-ignore@^5.2.0:
+ignore@^5.2.0, ignore@^5.2.4:
   version "5.2.4"
   resolved "https://registry.yarnpkg.com/ignore/-/ignore-5.2.4.tgz#a291c0c6178ff1b960befe47fcdec301674a6324"
   integrity sha512-MAb38BcSbH0eHNBxn7ql2NH/kX33OkB3lZ1BNdh7ENeRChHTYsTvWrMubiIAMNS2llXEEgZ1MUOBtXChP3kaFQ==
@@ -4790,6 +4786,11 @@ jest@^27.2.4:
     import-local "^3.0.2"
     jest-cli "^27.2.5"
 
+jose@^4.14.4:
+  version "4.14.4"
+  resolved "https://registry.yarnpkg.com/jose/-/jose-4.14.4.tgz#59e09204e2670c3164ee24cbfe7115c6f8bff9ca"
+  integrity sha512-j8GhLiKmUAh+dsFXlX1aJCbt5KMibuKb+d7j1JaOJG6s2UjX1PQlW+OKB/sD4a/5ZYF4RcmYmLSndOoU3Lt/3g==
+
 js-sdsl@^4.1.4:
   version "4.3.0"
   resolved "https://registry.yarnpkg.com/js-sdsl/-/js-sdsl-4.3.0.tgz#aeefe32a451f7af88425b11fdb5f58c90ae1d711"
@@ -4903,22 +4904,6 @@ jsonfile@^6.0.1:
   optionalDependencies:
     graceful-fs "^4.1.6"
 
-jsonwebtoken@^8.5.1:
-  version "8.5.1"
-  resolved "https://registry.yarnpkg.com/jsonwebtoken/-/jsonwebtoken-8.5.1.tgz#00e71e0b8df54c2121a1f26137df2280673bcc0d"
-  integrity sha512-XjwVfRS6jTMsqYs0EsuJ4LGxXV14zQybNd4L2r0UvbVnSF9Af8x7p5MzbJ90Ioz/9TI41/hTCvznF/loiSzn8w==
-  dependencies:
-    jws "^3.2.2"
-    lodash.includes "^4.3.0"
-    lodash.isboolean "^3.0.3"
-    lodash.isinteger "^4.0.4"
-    lodash.isnumber "^3.0.3"
-    lodash.isplainobject "^4.0.6"
-    lodash.isstring "^4.0.1"
-    lodash.once "^4.0.0"
-    ms "^2.1.1"
-    semver "^5.6.0"
-
 jstransformer@1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/jstransformer/-/jstransformer-1.0.0.tgz#ed8bf0921e2f3f1ed4d5c1a44f68709ed24722c3"
@@ -4938,23 +4923,6 @@ juice@^8.0.0:
     slick "^1.12.2"
     web-resource-inliner "^6.0.1"
 
-jwa@^1.4.1:
-  version "1.4.1"
-  resolved "https://registry.yarnpkg.com/jwa/-/jwa-1.4.1.tgz#743c32985cb9e98655530d53641b66c8645b039a"
-  integrity sha512-qiLX/xhEEFKUAJ6FiBMbes3w9ATzyk5W7Hvzpa/SLYdxNtng+gcurvrI7TbACjIXlsJyr05/S1oUhZrc63evQA==
-  dependencies:
-    buffer-equal-constant-time "1.0.1"
-    ecdsa-sig-formatter "1.0.11"
-    safe-buffer "^5.0.1"
-
-jws@^3.2.2:
-  version "3.2.2"
-  resolved "https://registry.yarnpkg.com/jws/-/jws-3.2.2.tgz#001099f3639468c9414000e99995fa52fb478304"
-  integrity sha512-YHlZCB6lMTllWDtSPHz/ZXTsi8S00usEV6v1tjq8tOUZzw7DpSDWVXjXDre6ed1w/pd495ODpHZYSdkRTsa0HA==
-  dependencies:
-    jwa "^1.4.1"
-    safe-buffer "^5.0.1"
-
 keyv@^3.0.0:
   version "3.1.0"
   resolved "https://registry.yarnpkg.com/keyv/-/keyv-3.1.0.tgz#ecc228486f69991e49e9476485a5be1e8fc5c4d9"
@@ -5058,46 +5026,11 @@ lodash.get@^4.4.2:
   resolved "https://registry.yarnpkg.com/lodash.get/-/lodash.get-4.4.2.tgz#2d177f652fa31e939b4438d5341499dfa3825e99"
   integrity sha1-LRd/ZS+jHpObRDjVNBSZ36OCXpk=
 
-lodash.includes@^4.3.0:
-  version "4.3.0"
-  resolved "https://registry.yarnpkg.com/lodash.includes/-/lodash.includes-4.3.0.tgz#60bb98a87cb923c68ca1e51325483314849f553f"
-  integrity sha1-YLuYqHy5I8aMoeUTJUgzFISfVT8=
-
-lodash.isboolean@^3.0.3:
-  version "3.0.3"
-  resolved "https://registry.yarnpkg.com/lodash.isboolean/-/lodash.isboolean-3.0.3.tgz#6c2e171db2a257cd96802fd43b01b20d5f5870f6"
-  integrity sha1-bC4XHbKiV82WgC/UOwGyDV9YcPY=
-
-lodash.isinteger@^4.0.4:
-  version "4.0.4"
-  resolved "https://registry.yarnpkg.com/lodash.isinteger/-/lodash.isinteger-4.0.4.tgz#619c0af3d03f8b04c31f5882840b77b11cd68343"
-  integrity sha1-YZwK89A/iwTDH1iChAt3sRzWg0M=
-
-lodash.isnumber@^3.0.3:
-  version "3.0.3"
-  resolved "https://registry.yarnpkg.com/lodash.isnumber/-/lodash.isnumber-3.0.3.tgz#3ce76810c5928d03352301ac287317f11c0b1ffc"
-  integrity sha1-POdoEMWSjQM1IwGsKHMX8RwLH/w=
-
-lodash.isplainobject@^4.0.6:
-  version "4.0.6"
-  resolved "https://registry.yarnpkg.com/lodash.isplainobject/-/lodash.isplainobject-4.0.6.tgz#7c526a52d89b45c45cc690b88163be0497f550cb"
-  integrity sha1-fFJqUtibRcRcxpC4gWO+BJf1UMs=
-
-lodash.isstring@^4.0.1:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/lodash.isstring/-/lodash.isstring-4.0.1.tgz#d527dfb5456eca7cc9bb95d5daeaf88ba54a5451"
-  integrity sha1-1SfftUVuynzJu5XV2ur4i6VKVFE=
-
 lodash.merge@^4.6.2:
   version "4.6.2"
   resolved "https://registry.yarnpkg.com/lodash.merge/-/lodash.merge-4.6.2.tgz#558aa53b43b661e1925a0afdfa36a9a1085fe57a"
   integrity sha512-0KpjqXRVvrYyCsX1swR/XTK0va6VQkQM6MNo7PqW77ByjAhoARA8EfrP1N4+KlKj8YS0ZUCtRT/YUuhyYDujIQ==
 
-lodash.once@^4.0.0:
-  version "4.1.1"
-  resolved "https://registry.yarnpkg.com/lodash.once/-/lodash.once-4.1.1.tgz#0dd3971213c7c56df880977d504c88fb471a97ac"
-  integrity sha1-DdOXEhPHxW34gJd9UEyI+0cal6w=
-
 lodash.sortby@^4.7.0:
   version "4.7.0"
   resolved "https://registry.yarnpkg.com/lodash.sortby/-/lodash.sortby-4.7.0.tgz#edd14c824e2cc9c1e0b0a1b42bb5210516a42438"
@@ -6140,6 +6073,11 @@ reflect-metadata@^0.1.13:
   resolved "https://registry.yarnpkg.com/reflect-metadata/-/reflect-metadata-0.1.13.tgz#67ae3ca57c972a2aa1642b10fe363fe32d49dc08"
   integrity sha512-Ts1Y/anZELhSsjMcU605fU9RE4Oi3p5ORujwbIKXfWa+0Zxs510Qrmrce5/Jowq3cHSZSJqBjypxmHarc+vEWg==
 
+regexp-tree@~0.1.1:
+  version "0.1.27"
+  resolved "https://registry.yarnpkg.com/regexp-tree/-/regexp-tree-0.1.27.tgz#2198f0ef54518ffa743fe74d983b56ffd631b6cd"
+  integrity sha512-iETxpjK6YoRWJG5o6hXLwvjYAoW+FEZn9os0PD/b6AP6xQwsa/Y7lCVgIixBbUPMfhu+i2LtdeAqVTgGlQarfA==
+
 regexp.prototype.flags@^1.4.3:
   version "1.4.3"
   resolved "https://registry.yarnpkg.com/regexp.prototype.flags/-/regexp.prototype.flags-1.4.3.tgz#87cab30f80f66660181a3bb7bf5981a872b367ac"
@@ -6279,6 +6217,13 @@ safe-regex-test@^1.0.0:
     get-intrinsic "^1.1.3"
     is-regex "^1.1.4"
 
+safe-regex@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/safe-regex/-/safe-regex-2.1.1.tgz#f7128f00d056e2fe5c11e81a1324dd974aadced2"
+  integrity sha512-rx+x8AMzKb5Q5lQ95Zoi6ZbJqwCLkqi3XuJXp5P3rT8OEc6sZCJG5AE5dU3lsgRr/F4Bs31jSlVN+j5KrsGu9A==
+  dependencies:
+    regexp-tree "~0.1.1"
+
 "safer-buffer@>= 2.1.2 < 3", "safer-buffer@>= 2.1.2 < 3.0.0":
   version "2.1.2"
   resolved "https://registry.yarnpkg.com/safer-buffer/-/safer-buffer-2.1.2.tgz#44fa161b0187b9549dd84bb91802f9bd8385cd6a"
@@ -6317,7 +6262,7 @@ semver@7.x, semver@^7.3.2, semver@^7.3.4:
   dependencies:
     lru-cache "^6.0.0"
 
-semver@^5.5.0, semver@^5.6.0, semver@^5.7.1:
+semver@^5.5.0, semver@^5.7.1:
   version "5.7.1"
   resolved "https://registry.yarnpkg.com/semver/-/semver-5.7.1.tgz#a954f931aeba508d307bbf069eff0c01c96116f7"
   integrity sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==
diff --git a/database/entity/0066-x-community-sendcoins-transactions_table/Transaction.ts b/database/entity/0066-x-community-sendcoins-transactions_table/Transaction.ts
new file mode 100644
index 000000000..4220cfadc
--- /dev/null
+++ b/database/entity/0066-x-community-sendcoins-transactions_table/Transaction.ts
@@ -0,0 +1,139 @@
+import Decimal from 'decimal.js-light'
+import { BaseEntity, Entity, PrimaryGeneratedColumn, Column, OneToOne, JoinColumn } from 'typeorm'
+import { DecimalTransformer } from '../../src/typeorm/DecimalTransformer'
+import { Contribution } from '../Contribution'
+
+@Entity('transactions')
+export class Transaction extends BaseEntity {
+  @PrimaryGeneratedColumn('increment', { unsigned: true })
+  id: number
+
+  @Column({ type: 'int', unsigned: true, unique: true, nullable: true, default: null })
+  previous: number | null
+
+  @Column({ name: 'type_id', unsigned: true, nullable: false })
+  typeId: number
+
+  @Column({
+    name: 'transaction_link_id',
+    type: 'int',
+    unsigned: true,
+    nullable: true,
+    default: null,
+  })
+  transactionLinkId?: number | null
+
+  @Column({
+    type: 'decimal',
+    precision: 40,
+    scale: 20,
+    nullable: false,
+    transformer: DecimalTransformer,
+  })
+  amount: Decimal
+
+  @Column({
+    type: 'decimal',
+    precision: 40,
+    scale: 20,
+    nullable: false,
+    transformer: DecimalTransformer,
+  })
+  balance: Decimal
+
+  @Column({
+    name: 'balance_date',
+    type: 'datetime',
+    default: () => 'CURRENT_TIMESTAMP',
+    nullable: false,
+  })
+  balanceDate: Date
+
+  @Column({
+    type: 'decimal',
+    precision: 40,
+    scale: 20,
+    nullable: false,
+    transformer: DecimalTransformer,
+  })
+  decay: Decimal
+
+  @Column({
+    name: 'decay_start',
+    type: 'datetime',
+    nullable: true,
+    default: null,
+  })
+  decayStart: Date | null
+
+  @Column({ length: 255, nullable: false, collation: 'utf8mb4_unicode_ci' })
+  memo: string
+
+  @Column({ name: 'creation_date', type: 'datetime', nullable: true, default: null })
+  creationDate: Date | null
+
+  @Column({ name: 'user_id', unsigned: true, nullable: false })
+  userId: number
+
+  @Column({
+    name: 'user_gradido_id',
+    type: 'varchar',
+    length: 36,
+    nullable: false,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  userGradidoID: string
+
+  @Column({
+    name: 'user_name',
+    type: 'varchar',
+    length: 512,
+    nullable: true,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  userName: string | null
+
+  @Column({
+    name: 'linked_user_id',
+    type: 'int',
+    unsigned: true,
+    nullable: true,
+    default: null,
+  })
+  linkedUserId?: number | null
+
+  @Column({
+    name: 'linked_user_gradido_id',
+    type: 'varchar',
+    length: 36,
+    nullable: true,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  linkedUserGradidoID: string | null
+
+  @Column({
+    name: 'linked_user_name',
+    type: 'varchar',
+    length: 512,
+    nullable: true,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  linkedUserName: string | null
+
+  @Column({
+    name: 'linked_transaction_id',
+    type: 'int',
+    unsigned: true,
+    nullable: true,
+    default: null,
+  })
+  linkedTransactionId?: number | null
+
+  @OneToOne(() => Contribution, (contribution) => contribution.transaction)
+  @JoinColumn({ name: 'id', referencedColumnName: 'transactionId' })
+  contribution?: Contribution | null
+
+  @OneToOne(() => Transaction)
+  @JoinColumn({ name: 'previous' })
+  previousTransaction?: Transaction | null
+}
diff --git a/database/entity/Transaction.ts b/database/entity/Transaction.ts
index 5365b0f70..4000e3c85 100644
--- a/database/entity/Transaction.ts
+++ b/database/entity/Transaction.ts
@@ -1 +1 @@
-export { Transaction } from './0036-unique_previous_in_transactions/Transaction'
+export { Transaction } from './0066-x-community-sendcoins-transactions_table/Transaction'
diff --git a/database/migrations/0066-x-community-sendcoins-transactions_table.ts b/database/migrations/0066-x-community-sendcoins-transactions_table.ts
new file mode 100644
index 000000000..425248c22
--- /dev/null
+++ b/database/migrations/0066-x-community-sendcoins-transactions_table.ts
@@ -0,0 +1,74 @@
+/* MIGRATION TO add users that have a transaction but do not exist */
+
+/* eslint-disable @typescript-eslint/explicit-module-boundary-types */
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+export async function upgrade(queryFn: (query: string, values?: any[]) => Promise<Array<any>>) {
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `previous` int(10) unsigned DEFAULT NULL NULL AFTER `id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `type_id` int(10) DEFAULT NULL NULL AFTER `previous`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `transaction_link_id` int(10) unsigned DEFAULT NULL NULL AFTER `type_id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `amount` decimal(40,20) DEFAULT NULL NULL AFTER `transaction_link_id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `balance` decimal(40,20) DEFAULT NULL NULL AFTER `amount`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `balance_date` datetime(3) DEFAULT current_timestamp(3) NOT NULL AFTER `balance`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `decay` decimal(40,20) DEFAULT NULL NULL AFTER `balance_date`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `decay_start` datetime(3) DEFAULT NULL NULL AFTER `decay`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `memo` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL AFTER `decay_start`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `creation_date` datetime(3) DEFAULT NULL NULL AFTER `memo`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `user_id` int(10) unsigned NOT NULL AFTER `creation_date`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` ADD COLUMN `user_gradido_id` char(36) DEFAULT NULL NULL AFTER `user_id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` ADD COLUMN `user_name` varchar(512) COLLATE utf8mb4_unicode_ci DEFAULT NULL NULL AFTER `user_gradido_id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `linked_user_id` int(10) unsigned DEFAULT NULL NULL AFTER `user_name`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` ADD COLUMN `linked_user_gradido_id` char(36) DEFAULT NULL NULL AFTER `linked_user_id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` ADD COLUMN `linked_user_name` varchar(512) COLLATE utf8mb4_unicode_ci DEFAULT NULL NULL AFTER `linked_user_gradido_id`;',
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `linked_transaction_id` int(10) DEFAULT NULL NULL AFTER `linked_user_name`;',
+  )
+  await queryFn(
+    `UPDATE transactions t, users u SET t.user_gradido_id = u.gradido_id, t.user_name = concat(u.first_name, ' ', u.last_name) WHERE t.user_id = u.id and t.user_gradido_id is null;`,
+  )
+  await queryFn(
+    'ALTER TABLE `transactions` MODIFY COLUMN `user_gradido_id` char(36) NOT NULL AFTER `user_id`;',
+  )
+  await queryFn(
+    `UPDATE transactions t, users u SET t.linked_user_gradido_id = u.gradido_id, t.linked_user_name = concat(u.first_name, ' ', u.last_name) WHERE t.linked_user_id = u.id and t.linked_user_gradido_id is null;`,
+  )
+}
+
+export async function downgrade(queryFn: (query: string, values?: any[]) => Promise<Array<any>>) {
+  await queryFn('ALTER TABLE `transactions` DROP COLUMN `user_gradido_id`;')
+  await queryFn('ALTER TABLE `transactions` DROP COLUMN `user_name`;')
+  await queryFn('ALTER TABLE `transactions` DROP COLUMN `linked_user_gradido_id`;')
+  await queryFn('ALTER TABLE `transactions` DROP COLUMN `linked_user_name`;')
+}
diff --git a/database/package.json b/database/package.json
index 23e358364..72d35dc04 100644
--- a/database/package.json
+++ b/database/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gradido-database",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "description": "Gradido Database Tool to execute database migrations",
   "main": "src/index.ts",
   "repository": "https://github.com/gradido/gradido/database",
diff --git a/deployment/bare_metal/.env.dist b/deployment/bare_metal/.env.dist
index f20a8c2d1..2c237d22c 100644
--- a/deployment/bare_metal/.env.dist
+++ b/deployment/bare_metal/.env.dist
@@ -57,7 +57,7 @@ EMAIL_CODE_REQUEST_TIME=10
 WEBHOOK_ELOPAGE_SECRET=secret
 
 # Federation
-FEDERATION_DHT_CONFIG_VERSION=v2.2023-02-07
+FEDERATION_DHT_CONFIG_VERSION=v3.2023-04-26
 # if you set the value of FEDERATION_DHT_TOPIC, the DHT hyperswarm will start to announce and listen 
 # on an hash created from this topic
 # FEDERATION_DHT_TOPIC=GRADIDO_HUB
diff --git a/deployment/bare_metal/nginx/sites-available/gradido.conf.ssl.template b/deployment/bare_metal/nginx/sites-available/gradido.conf.ssl.template
index ddb0724b0..a99327745 100644
--- a/deployment/bare_metal/nginx/sites-available/gradido.conf.ssl.template
+++ b/deployment/bare_metal/nginx/sites-available/gradido.conf.ssl.template
@@ -117,7 +117,7 @@ server {
 
     # TODO this could be a performance optimization
     #location /vue {
-    #    alias /var/www/html/gradido/frontend/dist;
+    #    alias /var/www/html/gradido/frontend/build;
     #    index index.html;
     #
     #    location ~* \.(png)$ {
diff --git a/deployment/bare_metal/nginx/sites-available/gradido.conf.template b/deployment/bare_metal/nginx/sites-available/gradido.conf.template
index 42a5a1851..f6149a818 100644
--- a/deployment/bare_metal/nginx/sites-available/gradido.conf.template
+++ b/deployment/bare_metal/nginx/sites-available/gradido.conf.template
@@ -103,7 +103,7 @@ server {
 
     # TODO this could be a performance optimization
     #location /vue {
-    #    alias /var/www/html/gradido/frontend/dist;
+    #    alias /var/www/html/gradido/frontend/build;
     #    index index.html;
     #
     #    location ~* \.(png)$ {
diff --git a/deployment/bare_metal/old/build_frontend.sh b/deployment/bare_metal/old/build_frontend.sh
index 4b3a8a444..a9103c19f 100755
--- a/deployment/bare_metal/old/build_frontend.sh
+++ b/deployment/bare_metal/old/build_frontend.sh
@@ -15,6 +15,6 @@ export NVM_DIR="/root/.nvm"
 $NPM_BIN install
 $NPM_BIN run build
 # prezip for faster deliver throw nginx
-cd dist
+cd build
 find . -type f -name "*.css" -exec gzip -9 -k {} \;
 find . -type f -name "*.js" -exec gzip -9 -k {} \;
diff --git a/deployment/bare_metal/start.sh b/deployment/bare_metal/start.sh
index b30d90f19..5d5744bd6 100755
--- a/deployment/bare_metal/start.sh
+++ b/deployment/bare_metal/start.sh
@@ -130,6 +130,15 @@ rm -Rf $PROJECT_ROOT/admin/node_modules
 rm -Rf $PROJECT_ROOT/dht-node/node_modules
 rm -Rf $PROJECT_ROOT/federation/node_modules
 
+# Remove build folders
+# we had problems with corrupted incremtal builds
+rm -Rf $PROJECT_ROOT/database/build
+rm -Rf $PROJECT_ROOT/backend/build
+rm -Rf $PROJECT_ROOT/frontend/build
+rm -Rf $PROJECT_ROOT/admin/build
+rm -Rf $PROJECT_ROOT/dht-node/build
+rm -Rf $PROJECT_ROOT/federation/build
+
 # Regenerate .env files
 cp -f $PROJECT_ROOT/database/.env $PROJECT_ROOT/database/.env.bak
 cp -f $PROJECT_ROOT/backend/.env $PROJECT_ROOT/backend/.env.bak
diff --git a/dht-node/.env.template b/dht-node/.env.template
index efe6158a6..a7603c15a 100644
--- a/dht-node/.env.template
+++ b/dht-node/.env.template
@@ -8,6 +8,10 @@ DB_PASSWORD=$DB_PASSWORD
 DB_DATABASE=gradido_community
 TYPEORM_LOGGING_RELATIVE_PATH=$TYPEORM_LOGGING_RELATIVE_PATH
 
+# Community
+COMMUNITY_NAME=$COMMUNITY_NAME
+COMMUNITY_DESCRIPTION=$COMMUNITY_DESCRIPTION
+
 # Federation
 FEDERATION_DHT_CONFIG_VERSION=$FEDERATION_DHT_CONFIG_VERSION
 # if you set the value of FEDERATION_DHT_TOPIC, the DHT hyperswarm will start to announce and listen 
diff --git a/dht-node/jest.config.js b/dht-node/jest.config.js
index fa00ed868..0b83d8edd 100644
--- a/dht-node/jest.config.js
+++ b/dht-node/jest.config.js
@@ -6,7 +6,7 @@ module.exports = {
   collectCoverageFrom: ['src/**/*.ts', '!**/node_modules/**', '!src/seeds/**', '!build/**'],
   coverageThreshold: {
     global: {
-      lines: 80,
+      lines: 83,
     },
   },
   setupFiles: ['<rootDir>/test/testSetup.ts'],
diff --git a/dht-node/package.json b/dht-node/package.json
index 1f8ba4505..d5dae0230 100644
--- a/dht-node/package.json
+++ b/dht-node/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gradido-dht-node",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "description": "Gradido dht-node module",
   "main": "src/index.ts",
   "repository": "https://github.com/gradido/gradido/",
@@ -23,7 +23,8 @@
     "nodemon": "^2.0.20",
     "ts-node": "^10.9.1",
     "tsconfig-paths": "^4.1.2",
-    "typescript": "^4.9.4"
+    "typescript": "^4.9.4",
+    "uuid": "^8.3.2"
   },
   "devDependencies": {
     "@types/dotenv": "^8.2.0",
@@ -31,6 +32,7 @@
     "@types/node": "^18.11.18",
     "@typescript-eslint/eslint-plugin": "^5.48.0",
     "@typescript-eslint/parser": "^5.48.0",
+    "@types/uuid": "^8.3.4",
     "eslint": "^8.31.0",
     "eslint-config-prettier": "^8.3.0",
     "eslint-config-standard": "^17.0.0",
diff --git a/dht-node/src/config/index.ts b/dht-node/src/config/index.ts
index 5c4676337..43949201b 100644
--- a/dht-node/src/config/index.ts
+++ b/dht-node/src/config/index.ts
@@ -3,13 +3,13 @@ import dotenv from 'dotenv'
 dotenv.config()
 
 const constants = {
-  DB_VERSION: '0065-refactor_communities_table',
+  DB_VERSION: '0066-x-community-sendcoins-transactions_table',
   LOG4JS_CONFIG: 'log4js-config.json',
   // default log level on production should be info
   LOG_LEVEL: process.env.LOG_LEVEL || 'info',
   CONFIG_VERSION: {
     DEFAULT: 'DEFAULT',
-    EXPECTED: 'v2.2023-02-07',
+    EXPECTED: 'v3.2023-04-26',
     CURRENT: '',
   },
 }
@@ -28,6 +28,12 @@ const database = {
     process.env.TYPEORM_LOGGING_RELATIVE_PATH || 'typeorm.dht-node.log',
 }
 
+const community = {
+  COMMUNITY_NAME: process.env.COMMUNITY_NAME || 'Gradido Entwicklung',
+  COMMUNITY_DESCRIPTION:
+    process.env.COMMUNITY_DESCRIPTION || 'Gradido-Community einer lokalen Entwicklungsumgebung.',
+}
+
 const federation = {
   FEDERATION_DHT_TOPIC: process.env.FEDERATION_DHT_TOPIC || 'GRADIDO_HUB',
   FEDERATION_DHT_SEED: process.env.FEDERATION_DHT_SEED || null,
@@ -51,6 +57,7 @@ const CONFIG = {
   ...constants,
   ...server,
   ...database,
+  ...community,
   ...federation,
 }
 
diff --git a/dht-node/src/dht_node/index.test.ts b/dht-node/src/dht_node/index.test.ts
index e76e6ac9f..ec172c4f8 100644
--- a/dht-node/src/dht_node/index.test.ts
+++ b/dht-node/src/dht_node/index.test.ts
@@ -5,8 +5,10 @@ import { startDHT } from './index'
 import DHT from '@hyperswarm/dht'
 import CONFIG from '@/config'
 import { logger } from '@test/testSetup'
+import { Community as DbCommunity } from '@entity/Community'
 import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
 import { testEnvironment, cleanDB } from '@test/helpers'
+import { validate as validateUUID, version as versionUUID } from 'uuid'
 
 CONFIG.FEDERATION_DHT_SEED = '64ebcb0e3ad547848fef4197c6e2332f'
 
@@ -114,6 +116,9 @@ describe('federation', () => {
     const hashSpy = jest.spyOn(DHT, 'hash')
     const keyPairSpy = jest.spyOn(DHT, 'keyPair')
     beforeEach(async () => {
+      CONFIG.FEDERATION_COMMUNITY_URL = 'https://test.gradido.net'
+      CONFIG.COMMUNITY_NAME = 'Gradido Test Community'
+      CONFIG.COMMUNITY_DESCRIPTION = 'Community to test the federation'
       DHT.mockClear()
       jest.clearAllMocks()
       await cleanDB()
@@ -132,6 +137,64 @@ describe('federation', () => {
       expect(DHT).toBeCalledWith({ keyPair: keyPairMock })
     })
 
+    it('stores the home community in community table ', async () => {
+      const result = await DbCommunity.find()
+      expect(result).toEqual([
+        expect.objectContaining({
+          id: expect.any(Number),
+          foreign: false,
+          url: 'https://test.gradido.net/api/',
+          publicKey: expect.any(Buffer),
+          communityUuid: expect.any(String),
+          authenticatedAt: null,
+          name: 'Gradido Test Community',
+          description: 'Community to test the federation',
+          creationDate: expect.any(Date),
+          createdAt: expect.any(Date),
+          updatedAt: null,
+        }),
+      ])
+      expect(validateUUID(result[0].communityUuid ? result[0].communityUuid : '')).toEqual(true)
+      expect(versionUUID(result[0].communityUuid ? result[0].communityUuid : '')).toEqual(4)
+    })
+
+    it('creates 3 entries in table federated_communities', async () => {
+      const result = await DbFederatedCommunity.find({ order: { id: 'ASC' } })
+      await expect(result).toHaveLength(3)
+      await expect(result).toEqual([
+        expect.objectContaining({
+          id: expect.any(Number),
+          foreign: false,
+          publicKey: expect.any(Buffer),
+          apiVersion: '1_0',
+          endPoint: 'https://test.gradido.net/api/',
+          lastAnnouncedAt: null,
+          createdAt: expect.any(Date),
+          updatedAt: null,
+        }),
+        expect.objectContaining({
+          id: expect.any(Number),
+          foreign: false,
+          publicKey: expect.any(Buffer),
+          apiVersion: '1_1',
+          endPoint: 'https://test.gradido.net/api/',
+          lastAnnouncedAt: null,
+          createdAt: expect.any(Date),
+          updatedAt: null,
+        }),
+        expect.objectContaining({
+          id: expect.any(Number),
+          foreign: false,
+          publicKey: expect.any(Buffer),
+          apiVersion: '2_0',
+          endPoint: 'https://test.gradido.net/api/',
+          lastAnnouncedAt: null,
+          createdAt: expect.any(Date),
+          updatedAt: null,
+        }),
+      ])
+    })
+
     describe('DHT node', () => {
       it('creates a server', () => {
         expect(nodeCreateServerMock).toBeCalled()
@@ -780,21 +843,21 @@ describe('federation', () => {
               socketEventMocks.open()
             })
 
-            it.skip('calls socket write with own api versions', () => {
+            it('calls socket write with own api versions', () => {
               expect(socketWriteMock).toBeCalledWith(
                 Buffer.from(
                   JSON.stringify([
                     {
                       api: '1_0',
-                      url: 'http://localhost/api/',
+                      url: 'https://test.gradido.net/api/',
                     },
                     {
                       api: '1_1',
-                      url: 'http://localhost/api/',
+                      url: 'https://test.gradido.net/api/',
                     },
                     {
                       api: '2_0',
-                      url: 'http://localhost/api/',
+                      url: 'https://test.gradido.net/api/',
                     },
                   ]),
                 ),
@@ -804,5 +867,101 @@ describe('federation', () => {
         })
       })
     })
+
+    describe('restart DHT', () => {
+      let homeCommunity: DbCommunity
+      let federatedCommunities: DbFederatedCommunity[]
+
+      describe('without changes', () => {
+        beforeEach(async () => {
+          DHT.mockClear()
+          jest.clearAllMocks()
+          homeCommunity = (await DbCommunity.find())[0]
+          federatedCommunities = await DbFederatedCommunity.find({ order: { id: 'ASC' } })
+          await startDHT(TEST_TOPIC)
+        })
+
+        it('does not change home community in community table except updated at column ', async () => {
+          await expect(DbCommunity.find()).resolves.toEqual([
+            {
+              ...homeCommunity,
+              updatedAt: expect.any(Date),
+            },
+          ])
+        })
+
+        it('rewrites the 3 entries in table federated_communities', async () => {
+          const result = await DbFederatedCommunity.find()
+          await expect(result).toHaveLength(3)
+          await expect(result).toEqual([
+            {
+              ...federatedCommunities[0],
+              id: expect.any(Number),
+              createdAt: expect.any(Date),
+            },
+            {
+              ...federatedCommunities[1],
+              id: expect.any(Number),
+              createdAt: expect.any(Date),
+            },
+            {
+              ...federatedCommunities[2],
+              id: expect.any(Number),
+              createdAt: expect.any(Date),
+            },
+          ])
+        })
+      })
+
+      describe('changeing URL, name and description', () => {
+        beforeEach(async () => {
+          CONFIG.FEDERATION_COMMUNITY_URL = 'https://test2.gradido.net'
+          CONFIG.COMMUNITY_NAME = 'Second Gradido Test Community'
+          CONFIG.COMMUNITY_DESCRIPTION = 'Another Community to test the federation'
+          DHT.mockClear()
+          jest.clearAllMocks()
+          homeCommunity = (await DbCommunity.find())[0]
+          federatedCommunities = await DbFederatedCommunity.find({ order: { id: 'ASC' } })
+          await startDHT(TEST_TOPIC)
+        })
+
+        it('updates URL, name, description and updated at columns  ', async () => {
+          await expect(DbCommunity.find()).resolves.toEqual([
+            {
+              ...homeCommunity,
+              url: 'https://test2.gradido.net/api/',
+              name: 'Second Gradido Test Community',
+              description: 'Another Community to test the federation',
+              updatedAt: expect.any(Date),
+            },
+          ])
+        })
+
+        it('rewrites the 3 entries in table federated_communities with new endpoint', async () => {
+          const result = await DbFederatedCommunity.find()
+          await expect(result).toHaveLength(3)
+          await expect(result).toEqual([
+            {
+              ...federatedCommunities[0],
+              id: expect.any(Number),
+              createdAt: expect.any(Date),
+              endPoint: 'https://test2.gradido.net/api/',
+            },
+            {
+              ...federatedCommunities[1],
+              id: expect.any(Number),
+              createdAt: expect.any(Date),
+              endPoint: 'https://test2.gradido.net/api/',
+            },
+            {
+              ...federatedCommunities[2],
+              id: expect.any(Number),
+              createdAt: expect.any(Date),
+              endPoint: 'https://test2.gradido.net/api/',
+            },
+          ])
+        })
+      })
+    })
   })
 })
diff --git a/dht-node/src/dht_node/index.ts b/dht-node/src/dht_node/index.ts
index 0db7a28c2..efd2ae2f8 100644
--- a/dht-node/src/dht_node/index.ts
+++ b/dht-node/src/dht_node/index.ts
@@ -4,10 +4,15 @@ import DHT from '@hyperswarm/dht'
 import { logger } from '@/server/logger'
 import CONFIG from '@/config'
 import { FederatedCommunity as DbFederatedCommunity } from '@entity/FederatedCommunity'
+import { Community as DbCommunity } from '@entity/Community'
+import { v4 as uuidv4 } from 'uuid'
 
 const KEY_SECRET_SEEDBYTES = 32
-const getSeed = (): Buffer | null =>
-  CONFIG.FEDERATION_DHT_SEED ? Buffer.alloc(KEY_SECRET_SEEDBYTES, CONFIG.FEDERATION_DHT_SEED) : null
+const getSeed = (): Buffer | null => {
+  return CONFIG.FEDERATION_DHT_SEED
+    ? Buffer.alloc(KEY_SECRET_SEEDBYTES, CONFIG.FEDERATION_DHT_SEED)
+    : null
+}
 
 const POLLTIME = 20000
 const SUCCESSTIME = 120000
@@ -28,10 +33,12 @@ export const startDHT = async (topic: string): Promise<void> => {
   try {
     const TOPIC = DHT.hash(Buffer.from(topic))
     const keyPair = DHT.keyPair(getSeed())
-    logger.info(`keyPairDHT: publicKey=${keyPair.publicKey.toString('hex')}`)
+    const pubKeyString = keyPair.publicKey.toString('hex')
+    logger.info(`keyPairDHT: publicKey=${pubKeyString}`)
     logger.debug(`keyPairDHT: secretKey=${keyPair.secretKey.toString('hex')}`)
+    await writeHomeCommunityEntry(pubKeyString)
 
-    const ownApiVersions = await writeFederatedHomeCommunityEnries(keyPair.publicKey)
+    const ownApiVersions = await writeFederatedHomeCommunityEntries(pubKeyString)
     logger.info(`ApiList: ${JSON.stringify(ownApiVersions)}`)
 
     const node = new DHT({ keyPair })
@@ -138,7 +145,7 @@ export const startDHT = async (topic: string): Promise<void> => {
         data.peers.forEach((peer: any) => {
           const pubKey = peer.publicKey.toString('hex')
           if (
-            pubKey !== keyPair.publicKey.toString('hex') &&
+            pubKey !== pubKeyString &&
             !successfulRequests.includes(pubKey) &&
             !errorfulRequests.includes(pubKey) &&
             !collectedPubKeys.includes(pubKey)
@@ -179,7 +186,7 @@ export const startDHT = async (topic: string): Promise<void> => {
   }
 }
 
-async function writeFederatedHomeCommunityEnries(pubKey: any): Promise<CommunityApi[]> {
+async function writeFederatedHomeCommunityEntries(pubKey: string): Promise<CommunityApi[]> {
   const homeApiVersions: CommunityApi[] = Object.values(ApiVersionType).map(function (apiEnum) {
     const comApi: CommunityApi = {
       api: apiEnum,
@@ -189,21 +196,65 @@ async function writeFederatedHomeCommunityEnries(pubKey: any): Promise<Community
   })
   try {
     // first remove privious existing homeCommunity entries
-    DbFederatedCommunity.createQueryBuilder().delete().where({ foreign: false }).execute()
-
-    homeApiVersions.forEach(async function (homeApi) {
-      const homeCom = new DbFederatedCommunity()
+    await DbFederatedCommunity.createQueryBuilder().delete().where({ foreign: false }).execute()
+    for (const homeApiVersion of homeApiVersions) {
+      const homeCom = DbFederatedCommunity.create()
       homeCom.foreign = false
-      homeCom.apiVersion = homeApi.api
-      homeCom.endPoint = homeApi.url
-      homeCom.publicKey = pubKey.toString('hex')
-
-      // this will NOT update the updatedAt column, to distingue between a normal update and the last announcement
+      homeCom.apiVersion = homeApiVersion.api
+      homeCom.endPoint = homeApiVersion.url
+      homeCom.publicKey = Buffer.from(pubKey)
       await DbFederatedCommunity.insert(homeCom)
-      logger.info(`federation home-community inserted successfully: ${JSON.stringify(homeCom)}`)
-    })
+      logger.info(`federation home-community inserted successfully:`, homeApiVersion)
+    }
   } catch (err) {
-    throw new Error(`Federation: Error writing HomeCommunity-Entries: ${err}`)
+    throw new Error(`Federation: Error writing federated HomeCommunity-Entries: ${err}`)
   }
   return homeApiVersions
 }
+
+async function writeHomeCommunityEntry(pubKey: string): Promise<void> {
+  try {
+    // check for existing homeCommunity entry
+    let homeCom = await DbCommunity.findOne({
+      foreign: false,
+      publicKey: Buffer.from(pubKey),
+    })
+    if (!homeCom) {
+      // check if a homecommunity with a different publicKey still exists
+      homeCom = await DbCommunity.findOne({ foreign: false })
+    }
+    if (homeCom) {
+      // simply update the existing entry, but it MUST keep the ID and UUID because of possible relations
+      homeCom.publicKey = Buffer.from(pubKey)
+      homeCom.url = CONFIG.FEDERATION_COMMUNITY_URL + '/api/'
+      homeCom.name = CONFIG.COMMUNITY_NAME
+      homeCom.description = CONFIG.COMMUNITY_DESCRIPTION
+      await DbCommunity.save(homeCom)
+      logger.info(`home-community updated successfully:`, homeCom)
+    } else {
+      // insert a new homecommunity entry including a new ID and a new but ensured unique UUID
+      homeCom = new DbCommunity()
+      homeCom.foreign = false
+      homeCom.publicKey = Buffer.from(pubKey)
+      homeCom.communityUuid = await newCommunityUuid()
+      homeCom.url = CONFIG.FEDERATION_COMMUNITY_URL + '/api/'
+      homeCom.name = CONFIG.COMMUNITY_NAME
+      homeCom.description = CONFIG.COMMUNITY_DESCRIPTION
+      homeCom.creationDate = new Date()
+      await DbCommunity.insert(homeCom)
+      logger.info(`home-community inserted successfully:`, homeCom)
+    }
+  } catch (err) {
+    throw new Error(`Federation: Error writing HomeCommunity-Entry: ${err}`)
+  }
+}
+
+const newCommunityUuid = async (): Promise<string> => {
+  while (true) {
+    const communityUuid = uuidv4()
+    if ((await DbCommunity.count({ where: { communityUuid } })) === 0) {
+      return communityUuid
+    }
+    logger.info('CommunityUuid creation conflict...', communityUuid)
+  }
+}
diff --git a/dht-node/src/index.ts b/dht-node/src/index.ts
index 2315c77df..d5e5f700b 100644
--- a/dht-node/src/index.ts
+++ b/dht-node/src/index.ts
@@ -21,9 +21,8 @@ async function main() {
     logger.fatal('Fatal: Database Version incorrect')
     throw new Error('Fatal: Database Version incorrect')
   }
-
-  // eslint-disable-next-line no-console
-  console.log(
+  logger.debug(`dhtseed set by CONFIG.FEDERATION_DHT_SEED=${CONFIG.FEDERATION_DHT_SEED}`)
+  logger.info(
     `starting Federation on ${CONFIG.FEDERATION_DHT_TOPIC} ${
       CONFIG.FEDERATION_DHT_SEED ? 'with seed...' : 'without seed...'
     }`,
diff --git a/dht-node/test/helpers.ts b/dht-node/test/helpers.ts
index aa7f94964..c5d6ce82b 100644
--- a/dht-node/test/helpers.ts
+++ b/dht-node/test/helpers.ts
@@ -22,8 +22,8 @@ const context = {
 
 export const cleanDB = async () => {
   // this only works as long we do not have foreign key constraints
-  for (let i = 0; i < entities.length; i++) {
-    await resetEntity(entities[i])
+  for (const entity of entities) {
+    await resetEntity(entity)
   }
 }
 
diff --git a/dht-node/yarn.lock b/dht-node/yarn.lock
index 5832ecd8b..85c4d35fa 100644
--- a/dht-node/yarn.lock
+++ b/dht-node/yarn.lock
@@ -769,6 +769,11 @@
   resolved "https://registry.yarnpkg.com/@types/stack-utils/-/stack-utils-2.0.1.tgz#20f18294f797f2209b5f65c8e3b5c8e8261d127c"
   integrity sha512-Hl219/BT5fLAaz6NDkSuhzasy49dwQS/DSdu4MdggFB8zcXv7vflBI3xp7FEmkmdDkBUI2bPUNeMttp2knYdxw==
 
+"@types/uuid@^8.3.4":
+  version "8.3.4"
+  resolved "https://registry.yarnpkg.com/@types/uuid/-/uuid-8.3.4.tgz#bd86a43617df0594787d38b735f55c805becf1bc"
+  integrity sha512-c/I8ZRb51j+pYGAu5CrFMRxqZ2ke4y2grEBO5AUjgSkSk+qT2Ea+OdWElz/OiMf5MNpn2b17kuVBwZLQJXzihw==
+
 "@types/yargs-parser@*":
   version "21.0.0"
   resolved "https://registry.yarnpkg.com/@types/yargs-parser/-/yargs-parser-21.0.0.tgz#0c60e537fa790f5f9472ed2776c2b71ec117351b"
@@ -4138,6 +4143,11 @@ url-parse@^1.5.3:
     querystringify "^2.1.1"
     requires-port "^1.0.0"
 
+uuid@^8.3.2:
+  version "8.3.2"
+  resolved "https://registry.yarnpkg.com/uuid/-/uuid-8.3.2.tgz#80d5b5ced271bb9af6c445f21a1a04c606cefbe2"
+  integrity sha512-+NYs2QeMWy+GWFOEm9xnn6HCDp0l7QBD7ml8zLUmJ+93Q5NF0NocErnwkTkXVFNiX3/fpC6afS8Dhb/gz7R7eg==
+
 v8-compile-cache-lib@^3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/v8-compile-cache-lib/-/v8-compile-cache-lib-3.0.1.tgz#6336e8d71965cb3d35a1bbb7868445a7c05264bf"
diff --git a/e2e-tests/cypress.config.ts b/e2e-tests/cypress.config.ts
index 7205ef9cb..e26259626 100644
--- a/e2e-tests/cypress.config.ts
+++ b/e2e-tests/cypress.config.ts
@@ -58,7 +58,7 @@ export default defineConfig({
       mailserverURL: 'http://localhost:1080',
       loginQuery: `mutation ($email: String!, $password: String!, $publisherId: Int) {
         login(email: $email, password: $password, publisherId: $publisherId) {
-          email
+          id
           firstName
           lastName
           language
diff --git a/e2e-tests/cypress/support/e2e.ts b/e2e-tests/cypress/support/e2e.ts
index 2f3557566..6866cae3e 100644
--- a/e2e-tests/cypress/support/e2e.ts
+++ b/e2e-tests/cypress/support/e2e.ts
@@ -35,6 +35,6 @@ Cypress.Commands.add('login', (email, password) => {
     }
 
     cy.visit('/')
-    window.localStorage.setItem('vuex', JSON.stringify(vuexToken))
+    window.localStorage.setItem('gradido-frontend', JSON.stringify(vuexToken))
   })
 })
diff --git a/federation/package.json b/federation/package.json
index 3173e77ab..861d3a077 100644
--- a/federation/package.json
+++ b/federation/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gradido-federation",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "description": "Gradido federation module providing Gradido-Hub-Federation and versioned API for inter community communication",
   "main": "src/index.ts",
   "repository": "https://github.com/gradido/gradido/federation",
diff --git a/federation/src/config/index.ts b/federation/src/config/index.ts
index 70a155d63..66d8a056c 100644
--- a/federation/src/config/index.ts
+++ b/federation/src/config/index.ts
@@ -11,7 +11,7 @@ Decimal.set({
 */
 
 const constants = {
-  DB_VERSION: '0065-refactor_communities_table',
+  DB_VERSION: '0066-x-community-sendcoins-transactions_table',
   // DECAY_START_TIME: new Date('2021-05-13 17:46:31-0000'), // GMT+0
   LOG4JS_CONFIG: 'log4js-config.json',
   // default log level on production should be info
diff --git a/federation/src/server/plugins.ts b/federation/src/server/plugins.ts
index 541c68ca2..38fdfbe9f 100644
--- a/federation/src/server/plugins.ts
+++ b/federation/src/server/plugins.ts
@@ -23,8 +23,8 @@ const setHeadersPlugin = {
 
 const filterVariables = (variables: any) => {
   const vars = clonedeep(variables)
-  if (vars.password) vars.password = '***'
-  if (vars.passwordNew) vars.passwordNew = '***'
+  if (vars && vars.password) vars.password = '***'
+  if (vars && vars.passwordNew) vars.passwordNew = '***'
   return vars
 }
 
diff --git a/frontend/.eslintignore b/frontend/.eslintignore
index 94934f9e7..e19e2338d 100644
--- a/frontend/.eslintignore
+++ b/frontend/.eslintignore
@@ -1,3 +1,3 @@
 node_modules/
-dist/
+build/
 coverage/
\ No newline at end of file
diff --git a/frontend/.gitignore b/frontend/.gitignore
index 0a541ba06..843f840a1 100644
--- a/frontend/.gitignore
+++ b/frontend/.gitignore
@@ -1,6 +1,6 @@
 .DS_Store
 node_modules/
-dist/
+build/
 .cache/
 npm-debug.log*
 yarn-debug.log*
diff --git a/frontend/Dockerfile b/frontend/Dockerfile
index a93199fad..1a4d8ca5c 100644
--- a/frontend/Dockerfile
+++ b/frontend/Dockerfile
@@ -84,7 +84,7 @@ CMD /bin/sh -c "yarn run dev"
 FROM base as production
 
 # Copy "binary"-files from build image
-COPY --from=build ${DOCKER_WORKDIR}/dist ./dist
+COPY --from=build ${DOCKER_WORKDIR}/build ./build
 # We also copy the node_modules express and serve-static for the run script
 COPY --from=build ${DOCKER_WORKDIR}/node_modules ./node_modules
 # Copy static files
diff --git a/frontend/package.json b/frontend/package.json
index f07284da6..c084a74e6 100755
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -1,13 +1,13 @@
 {
   "name": "bootstrap-vue-gradido-wallet",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "private": true,
   "scripts": {
     "start": "node run/server.js",
     "serve": "vue-cli-service serve --open",
     "build": "vue-cli-service build",
     "dev": "yarn run serve",
-    "analyse-bundle": "yarn build && webpack-bundle-analyzer dist/webpack.stats.json",
+    "analyse-bundle": "yarn build && webpack-bundle-analyzer build/webpack.stats.json",
     "lint": "eslint --max-warnings=0 --ext .js,.vue,.json .",
     "stylelint": "stylelint --max-warnings=0 '**/*.{scss,vue}'",
     "test": "cross-env TZ=UTC jest",
@@ -50,6 +50,7 @@
     "prettier": "^2.2.1",
     "qrcanvas-vue": "2.1.1",
     "regenerator-runtime": "^0.13.7",
+    "uuid": "^9.0.0",
     "vee-validate": "^3.4.5",
     "vue": "2.6.12",
     "vue-apollo": "^3.0.7",
diff --git a/frontend/run/server.js b/frontend/run/server.js
index 7d75acba8..4a49dcd75 100644
--- a/frontend/run/server.js
+++ b/frontend/run/server.js
@@ -9,10 +9,10 @@ const port = process.env.PORT || 3000
 // Express Server
 const app = express()
 // Serve files
-app.use(express.static(path.join(__dirname, '../dist')))
+app.use(express.static(path.join(__dirname, '../build')))
 // Default to index.html
 app.get('*', (req, res) => {
-  res.sendFile(path.join(__dirname, '../dist/index.html'))
+  res.sendFile(path.join(__dirname, '../build/index.html'))
 })
 
 app.listen(port, hostname, () => {
diff --git a/frontend/src/components/GddSend/TransactionConfirmationSend.vue b/frontend/src/components/GddSend/TransactionConfirmationSend.vue
index a9058558c..95a06ea3c 100644
--- a/frontend/src/components/GddSend/TransactionConfirmationSend.vue
+++ b/frontend/src/components/GddSend/TransactionConfirmationSend.vue
@@ -3,15 +3,23 @@
     <div class="bg-white appBoxShadow gradido-border-radius p-3">
       <div class="h3 mb-4">{{ $t('form.send_check') }}</div>
       <b-row class="mt-5">
-        <b-col cols="2"></b-col>
-        <b-col>
-          <div class="h4">{{ userName ? userName : identifier }}</div>
-          <div class="mt-3 h5">{{ $t('form.memo') }}</div>
-          <div>{{ memo }}</div>
-        </b-col>
-        <b-col cols="3">
-          <div class="small">{{ $t('send_gdd') }}</div>
-          <div>{{ amount | GDD }}</div>
+        <b-col cols="12">
+          <b-row class="mt-3">
+            <b-col class="h5">{{ $t('form.recipientCommunity') }}</b-col>
+            <b-col>{{ communityName }}</b-col>
+          </b-row>
+          <b-row>
+            <b-col class="h5">{{ $t('form.recipient') }}</b-col>
+            <b-col>{{ userName ? userName : identifier }}</b-col>
+          </b-row>
+          <b-row>
+            <b-col class="h5">{{ $t('form.amount') }}</b-col>
+            <b-col>{{ amount | GDD }}</b-col>
+          </b-row>
+          <b-row>
+            <b-col class="h5">{{ $t('form.memo') }}</b-col>
+            <b-col>{{ memo }}</b-col>
+          </b-row>
         </b-col>
       </b-row>
 
@@ -58,6 +66,8 @@
   </div>
 </template>
 <script>
+import { COMMUNITY_NAME } from '@/config'
+
 export default {
   name: 'TransactionConfirmationSend',
   props: {
@@ -70,6 +80,7 @@ export default {
   data() {
     return {
       disabled: false,
+      communityName: COMMUNITY_NAME,
     }
   },
 }
diff --git a/frontend/src/components/GddSend/TransactionForm.spec.js b/frontend/src/components/GddSend/TransactionForm.spec.js
index 41f69960e..e4cee20be 100644
--- a/frontend/src/components/GddSend/TransactionForm.spec.js
+++ b/frontend/src/components/GddSend/TransactionForm.spec.js
@@ -71,9 +71,9 @@ describe('TransactionForm', () => {
     })
 
     describe('with balance <= 0.00 GDD the form is disabled', () => {
-      it('has a disabled input field of type email', () => {
+      it('has a disabled input field of type text', () => {
         expect(
-          wrapper.find('div[data-test="input-email"]').find('input').attributes('disabled'),
+          wrapper.find('div[data-test="input-identifier"]').find('input').attributes('disabled'),
         ).toBe('disabled')
       })
 
@@ -116,51 +116,54 @@ describe('TransactionForm', () => {
           expect(wrapper.vm.radioSelected).toBe(SEND_TYPES.send)
         })
 
-        describe('email field', () => {
-          it('has an input field of type email', () => {
+        describe('identifier field', () => {
+          it('has an input field of type text', () => {
             expect(
-              wrapper.find('div[data-test="input-email"]').find('input').attributes('type'),
-            ).toBe('email')
+              wrapper.find('div[data-test="input-identifier"]').find('input').attributes('type'),
+            ).toBe('text')
           })
 
-          it('has a label form.receiver', () => {
-            expect(wrapper.find('div[data-test="input-email"]').find('label').text()).toBe(
+          it('has a label form.recipient', () => {
+            expect(wrapper.find('div[data-test="input-identifier"]').find('label').text()).toBe(
               'form.recipient',
             )
           })
 
-          it('has a placeholder "E-Mail"', () => {
+          it('has a placeholder for identifier', () => {
             expect(
-              wrapper.find('div[data-test="input-email"]').find('input').attributes('placeholder'),
-            ).toBe('form.email')
+              wrapper
+                .find('div[data-test="input-identifier"]')
+                .find('input')
+                .attributes('placeholder'),
+            ).toBe('form.identifier')
           })
 
-          it('flushes an error message when no valid email is given', async () => {
-            await wrapper.find('div[data-test="input-email"]').find('input').setValue('a')
+          it('flushes an error message when no valid identifier is given', async () => {
+            await wrapper.find('div[data-test="input-identifier"]').find('input').setValue('a')
             await flushPromises()
             expect(
-              wrapper.find('div[data-test="input-email"]').find('.invalid-feedback').text(),
-            ).toBe('validations.messages.email')
+              wrapper.find('div[data-test="input-identifier"]').find('.invalid-feedback').text(),
+            ).toBe('form.validation.valid-identifier')
           })
 
           // TODO:SKIPPED there is no check that the email being sent to is the same as the user's email.
           it.skip('flushes an error message when email is the email of logged in user', async () => {
             await wrapper
-              .find('div[data-test="input-email"]')
+              .find('div[data-test="input-identifier"]')
               .find('input')
               .setValue('user@example.org')
             await flushPromises()
             expect(
-              wrapper.find('div[data-test="input-email"]').find('.invalid-feedback').text(),
+              wrapper.find('div[data-test="input-identifier"]').find('.invalid-feedback').text(),
             ).toBe('form.validation.is-not')
           })
 
-          it('trims the email after blur', async () => {
+          it('trims the identifier after blur', async () => {
             await wrapper
-              .find('div[data-test="input-email"]')
+              .find('div[data-test="input-identifier"]')
               .find('input')
               .setValue('  valid@email.com  ')
-            await wrapper.find('div[data-test="input-email"]').find('input').trigger('blur')
+            await wrapper.find('div[data-test="input-identifier"]').find('input').trigger('blur')
             await flushPromises()
             expect(wrapper.vm.form.identifier).toBe('valid@email.com')
           })
@@ -304,7 +307,7 @@ Die ganze Welt bezwingen.“`)
 
           it('clears all fields on click', async () => {
             await wrapper
-              .find('div[data-test="input-email"]')
+              .find('div[data-test="input-identifier"]')
               .find('input')
               .setValue('someone@watches.tv')
             await wrapper.find('div[data-test="input-amount"]').find('input').setValue('87.23')
@@ -327,7 +330,7 @@ Die ganze Welt bezwingen.“`)
         describe('submit', () => {
           beforeEach(async () => {
             await wrapper
-              .find('div[data-test="input-email"]')
+              .find('div[data-test="input-identifier"]')
               .find('input')
               .setValue('someone@watches.tv')
             await wrapper.find('div[data-test="input-amount"]').find('input').setValue('87.23')
@@ -380,8 +383,8 @@ Die ganze Welt bezwingen.“`)
       })
 
       describe('query for username with success', () => {
-        it('has no email input field', () => {
-          expect(wrapper.find('div[data-test="input-email"]').exists()).toBe(false)
+        it('has no identifier input field', () => {
+          expect(wrapper.find('div[data-test="input-identifier"]').exists()).toBe(false)
         })
 
         it('queries the username', () => {
diff --git a/frontend/src/components/GddSend/TransactionForm.vue b/frontend/src/components/GddSend/TransactionForm.vue
index e887c47e6..d5b67d547 100644
--- a/frontend/src/components/GddSend/TransactionForm.vue
+++ b/frontend/src/components/GddSend/TransactionForm.vue
@@ -49,12 +49,20 @@
               <b-row>
                 <b-col>
                   <b-row>
+                    <b-col class="mb-4" cols="12" v-if="radioSelected === sendTypes.send">
+                      <b-row>
+                        <b-col>{{ $t('form.recipientCommunity') }}</b-col>
+                      </b-row>
+                      <b-row>
+                        <b-col class="font-weight-bold">{{ communityName }}</b-col>
+                      </b-row>
+                    </b-col>
                     <b-col cols="12" v-if="radioSelected === sendTypes.send">
                       <div v-if="!gradidoID">
-                        <input-email
+                        <input-identifier
                           :name="$t('form.recipient')"
                           :label="$t('form.recipient')"
-                          :placeholder="$t('form.email')"
+                          :placeholder="$t('form.identifier')"
                           v-model="form.identifier"
                           :disabled="isBalanceDisabled"
                           @onValidation="onValidation"
@@ -126,16 +134,17 @@
 </template>
 <script>
 import { SEND_TYPES } from '@/pages/Send'
-import InputEmail from '@/components/Inputs/InputEmail'
+import InputIdentifier from '@/components/Inputs/InputIdentifier'
 import InputAmount from '@/components/Inputs/InputAmount'
 import InputTextarea from '@/components/Inputs/InputTextarea'
 import { user as userQuery } from '@/graphql/queries'
 import { isEmpty } from 'lodash'
+import { COMMUNITY_NAME } from '@/config'
 
 export default {
   name: 'TransactionForm',
   components: {
-    InputEmail,
+    InputIdentifier,
     InputAmount,
     InputTextarea,
   },
@@ -155,6 +164,7 @@ export default {
       },
       radioSelected: this.selected,
       userName: '',
+      communityName: COMMUNITY_NAME,
     }
   },
   methods: {
diff --git a/frontend/src/components/Inputs/InputIdentifier.vue b/frontend/src/components/Inputs/InputIdentifier.vue
new file mode 100644
index 000000000..27b301cb5
--- /dev/null
+++ b/frontend/src/components/Inputs/InputIdentifier.vue
@@ -0,0 +1,68 @@
+<template>
+  <validation-provider
+    tag="div"
+    :rules="rules"
+    :name="name"
+    v-slot="{ errors, valid, validated, ariaInput, ariaMsg }"
+  >
+    <b-form-group :label="label" :label-for="labelFor" data-test="input-identifier">
+      <b-form-input
+        v-model="currentValue"
+        v-bind="ariaInput"
+        :id="labelFor"
+        :name="name"
+        :placeholder="placeholder"
+        type="text"
+        :state="validated ? valid : false"
+        trim
+        class="bg-248"
+        :disabled="disabled"
+        autocomplete="off"
+      ></b-form-input>
+      <b-form-invalid-feedback v-bind="ariaMsg">
+        {{ errors[0] }}
+      </b-form-invalid-feedback>
+    </b-form-group>
+  </validation-provider>
+</template>
+<script>
+export default {
+  name: 'InputEmail',
+  props: {
+    rules: {
+      default: () => {
+        return {
+          required: true,
+          validIdentifier: true,
+        }
+      },
+    },
+    name: { type: String, required: true },
+    label: { type: String, required: true },
+    placeholder: { type: String, required: true },
+    value: { type: String, required: true },
+    disabled: { type: Boolean, required: false, default: false },
+  },
+  data() {
+    return {
+      currentValue: this.value,
+    }
+  },
+  computed: {
+    labelFor() {
+      return this.name + '-input-field'
+    },
+  },
+  watch: {
+    currentValue() {
+      this.$emit('input', this.currentValue)
+    },
+    value() {
+      if (this.value !== this.currentValue) {
+        this.currentValue = this.value
+      }
+      this.$emit('onValidation')
+    },
+  },
+}
+</script>
diff --git a/frontend/src/components/Inputs/InputPasswordConfirmation.vue b/frontend/src/components/Inputs/InputPasswordConfirmation.vue
index 56d58d9ad..900cc0a0a 100644
--- a/frontend/src/components/Inputs/InputPasswordConfirmation.vue
+++ b/frontend/src/components/Inputs/InputPasswordConfirmation.vue
@@ -8,7 +8,7 @@
             containsLowercaseCharacter: true,
             containsUppercaseCharacter: true,
             containsNumericCharacter: true,
-            atLeastEightCharactera: true,
+            atLeastEightCharacters: true,
             atLeastOneSpecialCharater: true,
             noWhitespaceCharacters: true,
           }"
diff --git a/frontend/src/components/Inputs/InputUsername.vue b/frontend/src/components/Inputs/InputUsername.vue
new file mode 100644
index 000000000..e2048a781
--- /dev/null
+++ b/frontend/src/components/Inputs/InputUsername.vue
@@ -0,0 +1,71 @@
+<template>
+  <validation-provider
+    tag="div"
+    :rules="rules"
+    :name="name"
+    :bails="!showAllErrors"
+    :immediate="immediate"
+    vid="username"
+    v-slot="{ errors, valid, validated, ariaInput, ariaMsg }"
+  >
+    <b-form-group :label-for="labelFor">
+      <b-form-input
+        v-model="currentValue"
+        v-bind="ariaInput"
+        :id="labelFor"
+        :name="name"
+        :placeholder="placeholder"
+        type="text"
+        :state="validated ? valid : false"
+        autocomplete="off"
+      ></b-form-input>
+      <b-form-invalid-feedback v-bind="ariaMsg">
+        <div v-if="showAllErrors">
+          <span v-for="error in errors" :key="error">
+            {{ error }}
+            <br />
+          </span>
+        </div>
+        <div v-else>
+          {{ errors[0] }}
+        </div>
+      </b-form-invalid-feedback>
+    </b-form-group>
+  </validation-provider>
+</template>
+<script>
+export default {
+  name: 'InputUsername',
+  props: {
+    rules: {
+      default: () => {
+        return {
+          required: true,
+        }
+      },
+    },
+    name: { type: String, default: 'username' },
+    label: { type: String, default: 'Username' },
+    placeholder: { type: String, default: 'Username' },
+    value: { required: true, type: String },
+    showAllErrors: { type: Boolean, default: false },
+    immediate: { type: Boolean, default: false },
+    unique: { type: Boolean, required: true },
+  },
+  data() {
+    return {
+      currentValue: this.value,
+    }
+  },
+  computed: {
+    labelFor() {
+      return this.name + '-input-field'
+    },
+  },
+  watch: {
+    currentValue() {
+      this.$emit('input', this.currentValue)
+    },
+  },
+}
+</script>
diff --git a/frontend/src/components/LanguageSwitch.spec.js b/frontend/src/components/LanguageSwitch.spec.js
index 7f37c535a..6c733de7d 100644
--- a/frontend/src/components/LanguageSwitch.spec.js
+++ b/frontend/src/components/LanguageSwitch.spec.js
@@ -15,7 +15,7 @@ describe('LanguageSwitch', () => {
   let wrapper
 
   const state = {
-    email: 'he@ho.he',
+    gradidoID: 'current-user-id',
     language: null,
   }
 
diff --git a/frontend/src/components/LanguageSwitch.vue b/frontend/src/components/LanguageSwitch.vue
index 9d901ae9f..38194ba9c 100644
--- a/frontend/src/components/LanguageSwitch.vue
+++ b/frontend/src/components/LanguageSwitch.vue
@@ -31,7 +31,7 @@ export default {
     async saveLocale(locale) {
       // if (this.$i18n.locale === locale) return
       this.setLocale(locale)
-      if (this.$store.state.email) {
+      if (this.$store.state.gradidoID) {
         this.$apollo
           .mutate({
             mutation: updateUserInfos,
diff --git a/frontend/src/components/LanguageSwitch2.spec.js b/frontend/src/components/LanguageSwitch2.spec.js
index 0d2b485ec..e7ff6e8c6 100644
--- a/frontend/src/components/LanguageSwitch2.spec.js
+++ b/frontend/src/components/LanguageSwitch2.spec.js
@@ -15,7 +15,7 @@ describe('LanguageSwitch', () => {
   let wrapper
 
   const state = {
-    email: 'he@ho.he',
+    gradidoID: 'current-user-id',
     language: null,
   }
 
diff --git a/frontend/src/components/LanguageSwitch2.vue b/frontend/src/components/LanguageSwitch2.vue
index d398d2fe0..46b2a5277 100644
--- a/frontend/src/components/LanguageSwitch2.vue
+++ b/frontend/src/components/LanguageSwitch2.vue
@@ -59,7 +59,7 @@ export default {
     async saveLocale(locale) {
       if (this.$i18n.locale === locale) return
       this.setLocale(locale)
-      if (this.$store.state.email) {
+      if (this.$store.state.gradidoID) {
         this.$apollo
           .mutate({
             mutation: updateUserInfos,
diff --git a/frontend/src/components/Menu/Navbar.spec.js b/frontend/src/components/Menu/Navbar.spec.js
index 1e05df71d..a942c2644 100644
--- a/frontend/src/components/Menu/Navbar.spec.js
+++ b/frontend/src/components/Menu/Navbar.spec.js
@@ -20,7 +20,7 @@ const mocks = {
     state: {
       firstName: 'Testy',
       lastName: 'User',
-      email: 'testy.user@example.com',
+      gradidoID: 'current-user-id',
     },
   },
 }
@@ -64,8 +64,8 @@ describe('AuthNavbar', () => {
         )
       })
 
-      it('has the email address', () => {
-        // expect(wrapper.find('div.small:nth-child(2)').text()).toBe(wrapper.vm.$store.state.email)
+      // I think this should be username
+      it.skip('has the email address', () => {
         expect(wrapper.find('div[data-test="navbar-item-email"]').text()).toBe(
           wrapper.vm.$store.state.email,
         )
diff --git a/frontend/src/components/Menu/Navbar.vue b/frontend/src/components/Menu/Navbar.vue
index 73470a91b..648c273d0 100644
--- a/frontend/src/components/Menu/Navbar.vue
+++ b/frontend/src/components/Menu/Navbar.vue
@@ -29,10 +29,7 @@
               </div>
               <div>
                 <div data-test="navbar-item-username">{{ username.username }}</div>
-
-                <div data-test="navbar-item-email">
-                  {{ $store.state.email }}
-                </div>
+                <div data-test="navbar-item-email">{{ $store.state.email }}</div>
               </div>
             </div>
           </router-link>
diff --git a/frontend/src/components/TransactionRows/AmountAndNameRow.spec.js b/frontend/src/components/TransactionRows/AmountAndNameRow.spec.js
index 172f5f401..747cefe64 100644
--- a/frontend/src/components/TransactionRows/AmountAndNameRow.spec.js
+++ b/frontend/src/components/TransactionRows/AmountAndNameRow.spec.js
@@ -39,37 +39,5 @@ describe('AmountAndNameRow', () => {
         expect(wrapper.find('div.gdd-transaction-list-item-name').find('a').exists()).toBe(false)
       })
     })
-
-    describe('with linked user', () => {
-      beforeEach(async () => {
-        await wrapper.setProps({
-          linkedUser: { firstName: 'Bibi', lastName: 'Bloxberg', email: 'bibi@bloxberg.de' },
-        })
-      })
-
-      it('has a link with first and last name', () => {
-        expect(wrapper.find('div.gdd-transaction-list-item-name').text()).toBe('Bibi Bloxberg')
-      })
-
-      it('has a link', () => {
-        expect(wrapper.find('div.gdd-transaction-list-item-name').find('a').exists()).toBe(true)
-      })
-
-      describe('click link', () => {
-        beforeEach(async () => {
-          await wrapper.find('div.gdd-transaction-list-item-name').find('a').trigger('click')
-        })
-
-        it('emits  set tunneled email', () => {
-          expect(wrapper.emitted('set-tunneled-email')).toEqual([['bibi@bloxberg.de']])
-        })
-
-        it('pushes the route with query for email', () => {
-          expect(mocks.$router.push).toBeCalledWith({
-            path: '/send',
-          })
-        })
-      })
-    })
   })
 })
diff --git a/frontend/src/components/TransactionRows/AmountAndNameRow.vue b/frontend/src/components/TransactionRows/AmountAndNameRow.vue
index eb68d9f37..530fdf0e8 100644
--- a/frontend/src/components/TransactionRows/AmountAndNameRow.vue
+++ b/frontend/src/components/TransactionRows/AmountAndNameRow.vue
@@ -10,21 +10,7 @@
       </b-col>
       <b-col cols="7">
         <div class="gdd-transaction-list-item-name">
-          <span v-if="linkedUser && linkedUser.email">
-            <b-link @click.stop="tunnelEmail">
-              {{ itemText }}
-            </b-link>
-          </span>
-          <span v-else>{{ itemText }}</span>
-          <span v-if="linkId">
-            {{ $t('via_link') }}
-            <b-icon
-              icon="link45deg"
-              variant="muted"
-              class="m-mb-1"
-              :title="$t('gdd_per_link.redeemed-title')"
-            />
-          </span>
+          <span>{{ text }}</span>
         </div>
       </b-col>
     </b-row>
@@ -38,31 +24,9 @@ export default {
       type: String,
       required: true,
     },
-    linkedUser: {
-      type: Object,
-      required: false,
-    },
     text: {
       type: String,
-      required: false,
-    },
-    linkId: {
-      type: Number,
-      required: false,
-      default: null,
-    },
-  },
-  methods: {
-    tunnelEmail() {
-      this.$emit('set-tunneled-email', this.linkedUser.email)
-      this.$router.push({ path: '/send' })
-    },
-  },
-  computed: {
-    itemText() {
-      return this.linkedUser
-        ? this.linkedUser.firstName + ' ' + this.linkedUser.lastName
-        : this.text
+      required: true,
     },
   },
 }
diff --git a/frontend/src/components/TransactionRows/DurationRow.vue b/frontend/src/components/TransactionRows/DurationRow.vue
index 6f62d9dc5..f9b7873d6 100644
--- a/frontend/src/components/TransactionRows/DurationRow.vue
+++ b/frontend/src/components/TransactionRows/DurationRow.vue
@@ -12,7 +12,7 @@
 </template>
 <script>
 import { formatDistance } from 'date-fns'
-import { en, de, es, fr, nl } from 'date-fns/locale'
+import { enUS as en, de, es, fr, nl } from 'date-fns/locale'
 
 const locales = { en, de, es, fr, nl }
 
diff --git a/frontend/src/components/UserSettings/UserName.spec.js b/frontend/src/components/UserSettings/UserName.spec.js
new file mode 100644
index 000000000..012ba367a
--- /dev/null
+++ b/frontend/src/components/UserSettings/UserName.spec.js
@@ -0,0 +1,157 @@
+import { mount } from '@vue/test-utils'
+import UserName from './UserName'
+import flushPromises from 'flush-promises'
+
+import { toastErrorSpy, toastSuccessSpy } from '@test/testSetup'
+
+const localVue = global.localVue
+
+const mockAPIcall = jest.fn()
+
+const storeCommitMock = jest.fn()
+
+describe('UserName Form', () => {
+  let wrapper
+
+  const mocks = {
+    $t: jest.fn((t) => t),
+    $store: {
+      state: {
+        username: 'peter',
+      },
+      commit: storeCommitMock,
+    },
+    $apollo: {
+      mutate: mockAPIcall,
+    },
+  }
+
+  const Wrapper = () => {
+    return mount(UserName, { localVue, mocks })
+  }
+
+  describe('mount', () => {
+    beforeEach(() => {
+      wrapper = Wrapper()
+    })
+
+    it('renders the component', () => {
+      expect(wrapper.find('div#username_form').exists()).toBeTruthy()
+    })
+
+    it('has an edit icon', () => {
+      expect(wrapper.find('svg.bi-pencil').exists()).toBeTruthy()
+    })
+
+    it('renders the username', () => {
+      expect(wrapper.findAll('div.col').at(2).text()).toBe('peter')
+    })
+
+    describe('edit username', () => {
+      beforeEach(async () => {
+        await wrapper.find('svg.bi-pencil').trigger('click')
+      })
+
+      it('shows an cancel icon', () => {
+        expect(wrapper.find('svg.bi-x-circle').exists()).toBeTruthy()
+      })
+
+      it('closes the input when cancel icon is clicked', async () => {
+        await wrapper.find('svg.bi-x-circle').trigger('click')
+        expect(wrapper.find('input').exists()).toBeFalsy()
+      })
+
+      it('does not change the username when cancel is clicked', async () => {
+        await wrapper.find('input').setValue('petra')
+        await wrapper.find('svg.bi-x-circle').trigger('click')
+        expect(wrapper.findAll('div.col').at(2).text()).toBe('peter')
+      })
+
+      it('has a submit button', () => {
+        expect(wrapper.find('button[type="submit"]').exists()).toBeTruthy()
+      })
+
+      it('does not enable submit button when data is not changed', async () => {
+        await wrapper.find('form').trigger('keyup')
+        expect(wrapper.find('button[type="submit"]').attributes('disabled')).toBe('disabled')
+      })
+
+      describe('successfull submit', () => {
+        beforeEach(async () => {
+          mockAPIcall.mockResolvedValue({
+            data: {
+              updateUserInfos: {
+                validValues: 3,
+              },
+            },
+          })
+          jest.clearAllMocks()
+          await wrapper.find('input').setValue('petra')
+          await wrapper.find('form').trigger('keyup')
+          await wrapper.find('button[type="submit"]').trigger('click')
+          await flushPromises()
+        })
+
+        it('calls the API', () => {
+          expect(mockAPIcall).toBeCalledWith(
+            expect.objectContaining({
+              variables: {
+                alias: 'petra',
+              },
+            }),
+          )
+        })
+
+        it('commits username to store', () => {
+          expect(storeCommitMock).toBeCalledWith('username', 'petra')
+        })
+
+        it('toasts a success message', () => {
+          expect(toastSuccessSpy).toBeCalledWith('settings.username.change-success')
+        })
+
+        it('has an edit button again', () => {
+          expect(wrapper.find('svg.bi-pencil').exists()).toBeTruthy()
+        })
+      })
+
+      describe('submit results in server error', () => {
+        beforeEach(async () => {
+          mockAPIcall.mockRejectedValue({
+            message: 'Error',
+          })
+          jest.clearAllMocks()
+          await wrapper.find('input').setValue('petra')
+          await wrapper.find('form').trigger('keyup')
+          await wrapper.find('button[type="submit"]').trigger('click')
+          await flushPromises()
+        })
+
+        it('calls the API', () => {
+          expect(mockAPIcall).toBeCalledWith(
+            expect.objectContaining({
+              variables: {
+                alias: 'petra',
+              },
+            }),
+          )
+        })
+
+        it('toasts an error message', () => {
+          expect(toastErrorSpy).toBeCalledWith('Error')
+        })
+      })
+    })
+
+    describe('no username in store', () => {
+      beforeEach(() => {
+        mocks.$store.state.username = null
+        wrapper = Wrapper()
+      })
+
+      it('displays an information why to enter a username', () => {
+        expect(wrapper.findAll('div.col').at(2).text()).toBe('settings.username.no-username')
+      })
+    })
+  })
+})
diff --git a/frontend/src/components/UserSettings/UserName.vue b/frontend/src/components/UserSettings/UserName.vue
new file mode 100644
index 000000000..4fc1b2f3a
--- /dev/null
+++ b/frontend/src/components/UserSettings/UserName.vue
@@ -0,0 +1,130 @@
+<template>
+  <b-card id="username_form" class="card-border-radius card-background-gray">
+    <div>
+      <b-row class="mb-4 text-right">
+        <b-col class="text-right">
+          <a
+            class="cursor-pointer"
+            @click="showUserData ? (showUserData = !showUserData) : cancelEdit()"
+          >
+            <span class="pointer mr-3">{{ $t('settings.username.change-username') }}</span>
+            <b-icon v-if="showUserData" class="pointer ml-3" icon="pencil"></b-icon>
+            <b-icon v-else icon="x-circle" class="pointer ml-3" variant="danger"></b-icon>
+          </a>
+        </b-col>
+      </b-row>
+    </div>
+
+    <div>
+      <validation-observer ref="usernameObserver" v-slot="{ handleSubmit, invalid }">
+        <b-form @submit.stop.prevent="handleSubmit(onSubmit)">
+          <b-row class="mb-3">
+            <b-col class="col-12">
+              <small>
+                <b>{{ $t('form.username') }}</b>
+              </small>
+            </b-col>
+            <b-col v-if="showUserData" class="col-12">
+              <span v-if="username">
+                {{ username }}
+              </span>
+              <div v-else class="alert">
+                {{ $t('settings.username.no-username') }}
+              </div>
+            </b-col>
+            <b-col v-else class="col-12">
+              <input-username
+                v-model="username"
+                :name="$t('form.username')"
+                :placeholder="$t('form.username-placeholder')"
+                :showAllErrors="true"
+                :unique="true"
+                :rules="rules"
+              />
+            </b-col>
+          </b-row>
+          <b-row class="text-right" v-if="!showUserData">
+            <b-col>
+              <div class="text-right" ref="submitButton">
+                <b-button
+                  :variant="disabled(invalid) ? 'light' : 'success'"
+                  @click="onSubmit"
+                  type="submit"
+                  :disabled="disabled(invalid)"
+                >
+                  {{ $t('form.save') }}
+                </b-button>
+              </div>
+            </b-col>
+          </b-row>
+        </b-form>
+      </validation-observer>
+    </div>
+  </b-card>
+</template>
+<script>
+import { updateUserInfos } from '@/graphql/mutations'
+import InputUsername from '@/components/Inputs/InputUsername'
+
+export default {
+  name: 'UserName',
+  components: {
+    InputUsername,
+  },
+  data() {
+    return {
+      showUserData: true,
+      username: this.$store.state.username || '',
+      usernameUnique: false,
+      rules: {
+        required: true,
+        min: 3,
+        max: 20,
+        usernameAllowedChars: true,
+        usernameHyphens: true,
+        usernameUnique: true,
+      },
+    }
+  },
+  methods: {
+    cancelEdit() {
+      this.username = this.$store.state.username || ''
+      this.showUserData = true
+    },
+    async onSubmit(event) {
+      event.preventDefault()
+      this.$apollo
+        .mutate({
+          mutation: updateUserInfos,
+          variables: {
+            alias: this.username,
+          },
+        })
+        .then(() => {
+          this.$store.commit('username', this.username)
+          this.showUserData = true
+          this.toastSuccess(this.$t('settings.username.change-success'))
+        })
+        .catch((error) => {
+          this.toastError(error.message)
+        })
+    },
+    disabled(invalid) {
+      return !this.newUsername || invalid
+    },
+  },
+  computed: {
+    newUsername() {
+      return this.username !== this.$store.state.username
+    },
+  },
+}
+</script>
+<style>
+.cursor-pointer {
+  cursor: pointer;
+}
+div.alert {
+  color: red;
+}
+</style>
diff --git a/frontend/src/components/UserSettings/UserNewsletter.spec.js b/frontend/src/components/UserSettings/UserNewsletter.spec.js
index b211ec169..7ae3ddd7c 100644
--- a/frontend/src/components/UserSettings/UserNewsletter.spec.js
+++ b/frontend/src/components/UserSettings/UserNewsletter.spec.js
@@ -18,7 +18,6 @@ describe('UserCard_Newsletter', () => {
     $store: {
       state: {
         language: 'de',
-        email: 'peter@lustig.de',
         newsletterState: true,
       },
       commit: storeCommitMock,
diff --git a/frontend/src/graphql/mutations.js b/frontend/src/graphql/mutations.js
index 65bdd7497..8a281aad9 100644
--- a/frontend/src/graphql/mutations.js
+++ b/frontend/src/graphql/mutations.js
@@ -26,6 +26,7 @@ export const forgotPassword = gql`
 
 export const updateUserInfos = gql`
   mutation(
+    $alias: String
     $firstName: String
     $lastName: String
     $password: String
@@ -35,6 +36,7 @@ export const updateUserInfos = gql`
     $hideAmountGDT: Boolean
   ) {
     updateUserInfos(
+      alias: $alias
       firstName: $firstName
       lastName: $lastName
       password: $password
@@ -145,7 +147,7 @@ export const login = gql`
   mutation($email: String!, $password: String!, $publisherId: Int) {
     login(email: $email, password: $password, publisherId: $publisherId) {
       gradidoID
-      email
+      alias
       firstName
       lastName
       language
diff --git a/frontend/src/graphql/queries.js b/frontend/src/graphql/queries.js
index d0cbc145d..f254b93cc 100644
--- a/frontend/src/graphql/queries.js
+++ b/frontend/src/graphql/queries.js
@@ -3,7 +3,7 @@ import gql from 'graphql-tag'
 export const verifyLogin = gql`
   query {
     verifyLogin {
-      email
+      gradidoID
       firstName
       lastName
       language
@@ -40,7 +40,6 @@ export const transactionsQuery = gql`
           firstName
           lastName
           gradidoID
-          email
         }
         decay {
           decay
@@ -90,6 +89,12 @@ export const queryOptIn = gql`
   }
 `
 
+export const checkUsername = gql`
+  query($username: String!) {
+    checkUsername(username: $username)
+  }
+`
+
 export const queryTransactionLink = gql`
   query($code: String!) {
     queryTransactionLink(code: $code) {
@@ -102,9 +107,9 @@ export const queryTransactionLink = gql`
         redeemedAt
         deletedAt
         user {
+          gradidoID
           firstName
           publisherId
-          email
         }
       }
       ... on ContributionLink {
diff --git a/frontend/src/layouts/DashboardLayout.spec.js b/frontend/src/layouts/DashboardLayout.spec.js
index 9f68199da..a2a666591 100644
--- a/frontend/src/layouts/DashboardLayout.spec.js
+++ b/frontend/src/layouts/DashboardLayout.spec.js
@@ -43,7 +43,6 @@ const mocks = {
   $store: {
     dispatch: storeDispatchMock,
     state: {
-      email: 'user@example.org',
       publisherId: 123,
       firstName: 'User',
       lastName: 'Example',
@@ -260,34 +259,6 @@ describe('DashboardLayout', () => {
         })
       })
 
-      describe.skip('elopage URI', () => {
-        describe('user has no publisher ID and no elopage', () => {
-          beforeEach(() => {
-            mocks.$store.state.publisherId = null
-            mocks.$store.state.hasElopage = false
-            wrapper = Wrapper()
-          })
-
-          it('links to basic-de', () => {
-            expect(wrapper.vm.elopageUri).toBe(
-              'https://elopage.com/s/gradido/basic-de/payment?locale=en&prid=111&pid=2896&firstName=User&lastName=Example&email=user@example.org',
-            )
-          })
-        })
-
-        describe('user has elopage', () => {
-          beforeEach(() => {
-            mocks.$store.state.publisherId = '123'
-            mocks.$store.state.hasElopage = true
-            wrapper = Wrapper()
-          })
-
-          it('links to sign in for elopage', () => {
-            expect(wrapper.vm.elopageUri).toBe('https://elopage.com/s/gradido/sign_in?locale=en')
-          })
-        })
-      })
-
       describe.skip('admin method', () => {
         const windowLocationMock = jest.fn()
         beforeEach(() => {
diff --git a/frontend/src/locales/de.json b/frontend/src/locales/de.json
index a5357e6d9..136a07bbf 100644
--- a/frontend/src/locales/de.json
+++ b/frontend/src/locales/de.json
@@ -142,6 +142,7 @@
     "from": "Von",
     "generate_now": "Jetzt generieren",
     "hours": "Stunden",
+    "identifier": "Email, Nutzername oder Gradido ID",
     "lastname": "Nachname",
     "memo": "Nachricht",
     "message": "Nachricht",
@@ -153,6 +154,7 @@
     "password_new_repeat": "Neues Passwort wiederholen",
     "password_old": "Altes Passwort",
     "recipient": "Empfänger",
+    "recipientCommunity": "Gemeinschaft des Empfängers",
     "reply": "Antworten",
     "reset": "Zurücksetzen",
     "save": "Speichern",
@@ -166,12 +168,16 @@
     "thx": "Danke",
     "to": "bis",
     "to1": "an",
+    "username": "Nutzername",
+    "username-placeholder": "Gebe einen eindeutigen Nutzernamen ein",
     "validation": {
       "gddCreationTime": "Das Feld {_field_} muss eine Zahl zwischen {min} und {max} mit höchstens einer Nachkommastelle sein",
       "gddSendAmount": "Das Feld {_field_} muss eine Zahl zwischen {min} und {max} mit höchstens zwei Nachkommastellen sein",
       "is-not": "Du kannst dir selbst keine Gradidos überweisen",
-      "usernmae-regex": "Der Username muss mit einem Buchstaben beginnen, auf den mindestens zwei alpha-numerische Zeichen folgen müssen.",
-      "usernmae-unique": "Der Username ist bereits vergeben."
+      "username-allowed-chars": "Der Nutzername darf nur aus Buchstaben (ohne Umlaute), Zahlen, Binde- oder Unterstrichen bestehen.",
+      "username-hyphens": "Binde- oder Unterstriche müssen zwischen Buchstaben oder Zahlen stehen.",
+      "username-unique": "Der Nutzername ist bereits vergeben.",
+      "valid-identifier": "Muss eine Email, ein Nutzernamen oder eine gradido ID sein."
     },
     "your_amount": "Dein Betrag"
   },
@@ -319,7 +325,12 @@
       "subtitle": "Wenn du dein Passwort vergessen hast, kannst du es hier zurücksetzen."
     },
     "showAmountGDD": "Dein GDD Betrag ist sichtbar.",
-    "showAmountGDT": "Dein GDT Betrag ist sichtbar."
+    "showAmountGDT": "Dein GDT Betrag ist sichtbar.",
+    "username": {
+      "change-success": "Dein Nutzername wurde erfolgreich geändert.",
+      "change-username": "Nutzername ändern",
+      "no-username": "Bitte gebe einen Nutzernamen ein. Damit hilfst du anderen Benutzern dich zu finden, ohne deine Email preisgeben zu müssen."
+    }
   },
   "signin": "Anmelden",
   "signup": "Registrieren",
diff --git a/frontend/src/locales/en.json b/frontend/src/locales/en.json
index 42f22f709..f895145ae 100644
--- a/frontend/src/locales/en.json
+++ b/frontend/src/locales/en.json
@@ -142,6 +142,7 @@
     "from": "from",
     "generate_now": "Generate now",
     "hours": "Hours",
+    "identifier": "Email, username or gradido ID",
     "lastname": "Lastname",
     "memo": "Message",
     "message": "Message",
@@ -153,6 +154,7 @@
     "password_new_repeat": "Repeat new password",
     "password_old": "Old password",
     "recipient": "Recipient",
+    "recipientCommunity": "Community of the recipient",
     "reply": "Reply",
     "reset": "Reset",
     "save": "Save",
@@ -166,12 +168,16 @@
     "thx": "Thank you",
     "to": "to",
     "to1": "to",
+    "username": "Username",
+    "username-placeholder": "Enter a unique username",
     "validation": {
       "gddCreationTime": "The field {_field_} must be a number between {min} and {max} with at most one decimal place.",
       "gddSendAmount": "The {_field_} field must be a number between {min} and {max} with at most two digits after the decimal point",
       "is-not": "You cannot send Gradidos to yourself",
-      "usernmae-regex": "The username must start with a letter, followed by at least two alphanumeric characters.",
-      "usernmae-unique": "This username is already taken."
+      "username-allowed-chars": "The username may only contain letters, numbers, hyphens or underscores.",
+      "username-hyphens": "Hyphens or underscores must be in between letters or numbers.",
+      "username-unique": "This username is already taken.",
+      "valid-identifier": "Must be a valid email, username or gradido ID."
     },
     "your_amount": "Your amount"
   },
@@ -319,7 +325,12 @@
       "subtitle": "If you have forgotten your password, you can reset it here."
     },
     "showAmountGDD": "Your GDD amount is visible.",
-    "showAmountGDT": "Your GDT amount is visible."
+    "showAmountGDT": "Your GDT amount is visible.",
+    "username": {
+      "change-success": "Your username has been changed successfully.",
+      "change-username": "Change username",
+      "no-username": "Please enter a username. This helps other users to find you without exposing your email."
+    }
   },
   "signin": "Sign in",
   "signup": "Sign up",
diff --git a/frontend/src/main.js b/frontend/src/main.js
index 4809e490c..f31311ab2 100755
--- a/frontend/src/main.js
+++ b/frontend/src/main.js
@@ -27,7 +27,7 @@ const filters = loadFilters(i18n)
 Vue.filter('amount', filters.amount)
 Vue.filter('GDD', filters.GDD)
 
-loadAllRules(i18n)
+loadAllRules(i18n, apolloProvider.defaultClient)
 
 addNavigationGuards(router, store, apolloProvider.defaultClient)
 
diff --git a/frontend/src/pages/Login.spec.js b/frontend/src/pages/Login.spec.js
index 14bf77aa6..511685efa 100644
--- a/frontend/src/pages/Login.spec.js
+++ b/frontend/src/pages/Login.spec.js
@@ -146,6 +146,10 @@ describe('Login', () => {
             expect(mockStoreDispach).toBeCalledWith('login', 'token')
           })
 
+          it('commits email to store', () => {
+            expect(mockStoreCommit).toBeCalledWith('email', 'user@example.org')
+          })
+
           it('hides the spinner', () => {
             expect(spinnerHideMock).toBeCalled()
           })
diff --git a/frontend/src/pages/Login.vue b/frontend/src/pages/Login.vue
index c02ee0e45..6fd435c2d 100644
--- a/frontend/src/pages/Login.vue
+++ b/frontend/src/pages/Login.vue
@@ -100,6 +100,7 @@ export default {
             data: { login },
           } = result
           this.$store.dispatch('login', login)
+          this.$store.commit('email', this.form.email)
           await loader.hide()
           if (this.$route.params.code) {
             this.$router.push(`/redeem/${this.$route.params.code}`)
diff --git a/frontend/src/pages/Send.spec.js b/frontend/src/pages/Send.spec.js
index 3aae5a83e..1001d0c58 100644
--- a/frontend/src/pages/Send.spec.js
+++ b/frontend/src/pages/Send.spec.js
@@ -66,8 +66,11 @@ describe('Send', () => {
       beforeEach(async () => {
         const transactionForm = wrapper.findComponent({ name: 'TransactionForm' })
         await transactionForm.findAll('input[type="radio"]').at(0).setChecked()
-        await transactionForm.find('input[type="email"]').setValue('user@example.org')
-        await transactionForm.find('input[type="text"]').setValue('23.45')
+        await transactionForm
+          .find('[data-test="input-identifier"]')
+          .find('input')
+          .setValue('user@example.org')
+        await transactionForm.find('[data-test="input-amount"]').find('input').setValue('23.45')
         await transactionForm.find('textarea').setValue('Make the best of it!')
         await transactionForm.find('form').trigger('submit')
         await flushPromises()
@@ -91,8 +94,12 @@ describe('Send', () => {
           })
 
           it('restores the previous data in the formular', () => {
-            expect(wrapper.find("input[type='email']").vm.$el.value).toBe('user@example.org')
-            expect(wrapper.find("input[type='text']").vm.$el.value).toBe('23.45')
+            expect(wrapper.find('[data-test="input-identifier"]').find('input').vm.$el.value).toBe(
+              'user@example.org',
+            )
+            expect(wrapper.find('[data-test="input-amount"]').find('input').vm.$el.value).toBe(
+              '23.45',
+            )
             expect(wrapper.find('textarea').vm.$el.value).toBe('Make the best of it!')
           })
         })
@@ -175,7 +182,10 @@ describe('Send', () => {
 
       it('has no email input field', () => {
         expect(
-          wrapper.findComponent({ name: 'TransactionForm' }).find('input[type="email"]').exists(),
+          wrapper
+            .findComponent({ name: 'TransactionForm' })
+            .find('[data-test="input-identifier"]')
+            .exists(),
         ).toBe(false)
       })
 
@@ -183,7 +193,7 @@ describe('Send', () => {
         beforeEach(async () => {
           jest.clearAllMocks()
           const transactionForm = wrapper.findComponent({ name: 'TransactionForm' })
-          await transactionForm.find('input[type="text"]').setValue('34.56')
+          await transactionForm.find('[data-test="input-amount"]').find('input').setValue('34.56')
           await transactionForm.find('textarea').setValue('Make the best of it!')
           await transactionForm.find('form').trigger('submit')
           await flushPromises()
@@ -243,7 +253,7 @@ describe('Send', () => {
         })
         const transactionForm = wrapper.findComponent({ name: 'TransactionForm' })
         await transactionForm.findAll('input[type="radio"]').at(1).setChecked()
-        await transactionForm.find('input[type="text"]').setValue('56.78')
+        await transactionForm.find('[data-test="input-amount"]').find('input').setValue('56.78')
         await transactionForm.find('textarea').setValue('Make the best of the link!')
         await transactionForm.find('form').trigger('submit')
         await flushPromises()
diff --git a/frontend/src/pages/Settings.vue b/frontend/src/pages/Settings.vue
index 530484d9a..c5ca00f08 100644
--- a/frontend/src/pages/Settings.vue
+++ b/frontend/src/pages/Settings.vue
@@ -3,6 +3,8 @@
     <user-card :balance="balance" :transactionCount="transactionCount"></user-card>
     <user-data />
     <hr />
+    <user-name />
+    <hr />
     <user-password />
     <hr />
     <user-language />
@@ -13,6 +15,7 @@
 <script>
 import UserCard from '@/components/UserSettings/UserCard'
 import UserData from '@/components/UserSettings/UserData'
+import UserName from '@/components/UserSettings/UserName'
 import UserPassword from '@/components/UserSettings/UserPassword'
 import UserLanguage from '@/components/UserSettings/UserLanguage'
 import UserNewsletter from '@/components/UserSettings/UserNewsletter'
@@ -22,6 +25,7 @@ export default {
   components: {
     UserCard,
     UserData,
+    UserName,
     UserPassword,
     UserLanguage,
     UserNewsletter,
diff --git a/frontend/src/pages/TransactionLink.spec.js b/frontend/src/pages/TransactionLink.spec.js
index adbb25226..0b9cbb5ef 100644
--- a/frontend/src/pages/TransactionLink.spec.js
+++ b/frontend/src/pages/TransactionLink.spec.js
@@ -32,7 +32,7 @@ apolloQueryMock.mockResolvedValue({
       validUntil: transactionLinkValidExpireDate(),
       redeemedAt: '2022-03-18T10:08:43.000Z',
       deletedAt: null,
-      user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+      user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'other-user-id' },
     },
   },
 })
@@ -44,7 +44,7 @@ const mocks = {
     state: {
       token: null,
       tokenTime: null,
-      email: 'bibi@bloxberg.de',
+      gradidoID: 'current-user-id',
     },
   },
   $apollo: {
@@ -101,7 +101,7 @@ describe('TransactionLink', () => {
               validUntil: transactionLinkValidExpireDate(),
               redeemedAt: '2022-03-18T10:08:43.000Z',
               deletedAt: now,
-              user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+              user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'other-user-id' },
             },
           },
         })
@@ -132,7 +132,7 @@ describe('TransactionLink', () => {
               validUntil: '2020-03-18T10:08:43.000Z',
               redeemedAt: '2022-03-18T10:08:43.000Z',
               deletedAt: null,
-              user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+              user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'other-user-id' },
             },
           },
         })
@@ -163,7 +163,7 @@ describe('TransactionLink', () => {
               validUntil: transactionLinkValidExpireDate(),
               redeemedAt: '2022-03-18T10:08:43.000Z',
               deletedAt: null,
-              user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+              user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'other-user-id' },
             },
           },
         })
@@ -195,7 +195,7 @@ describe('TransactionLink', () => {
               validUntil: transactionLinkValidExpireDate(),
               redeemedAt: null,
               deletedAt: null,
-              user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+              user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'other-user-id' },
             },
           },
         })
@@ -239,7 +239,7 @@ describe('TransactionLink', () => {
                   validUntil: transactionLinkValidExpireDate(),
                   redeemedAt: null,
                   deletedAt: null,
-                  user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+                  user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'current-user-id' },
                 },
               },
             })
@@ -275,7 +275,7 @@ describe('TransactionLink', () => {
                   validUntil: transactionLinkValidExpireDate(),
                   redeemedAt: null,
                   deletedAt: null,
-                  user: { firstName: 'Peter', publisherId: 0, email: 'peter@listig.de' },
+                  user: { firstName: 'Peter', publisherId: 0, gradidoID: 'other-user-id' },
                 },
               },
             })
@@ -351,7 +351,7 @@ describe('TransactionLink', () => {
                 validUntil: transactionLinkValidExpireDate(),
                 redeemedAt: null,
                 deletedAt: null,
-                user: { firstName: 'Bibi', publisherId: 0, email: 'bibi@bloxberg.de' },
+                user: { firstName: 'Bibi', publisherId: 0, gradidoID: 'other-user-id' },
               },
             },
           })
diff --git a/frontend/src/pages/TransactionLink.vue b/frontend/src/pages/TransactionLink.vue
index 0aa4cfa7d..adc3cb50b 100644
--- a/frontend/src/pages/TransactionLink.vue
+++ b/frontend/src/pages/TransactionLink.vue
@@ -139,7 +139,7 @@ export default {
         if (this.tokenExpiresInSeconds < 5) return `LOGGED_OUT`
 
         // logged in, nicht berechtigt einzulösen, eigener link
-        if (this.linkData.user && this.$store.state.email === this.linkData.user.email) {
+        if (this.linkData.user && this.$store.state.gradidoID === this.linkData.user.gradidoID) {
           return `SELF_CREATOR`
         }
 
diff --git a/frontend/src/store/store.js b/frontend/src/store/store.js
index 1cd874c06..4036626d8 100644
--- a/frontend/src/store/store.js
+++ b/frontend/src/store/store.js
@@ -13,12 +13,12 @@ export const mutations = {
     localeChanged(language)
     state.language = language
   },
-  email: (state, email) => {
-    state.email = email
+  gradidoID: (state, gradidoID) => {
+    state.gradidoID = gradidoID
+  },
+  username: (state, username) => {
+    state.username = username
   },
-  // username: (state, username) => {
-  //   state.username = username
-  // },
   firstName: (state, firstName) => {
     state.firstName = firstName
   },
@@ -53,13 +53,16 @@ export const mutations = {
   hideAmountGDT: (state, hideAmountGDT) => {
     state.hideAmountGDT = !!hideAmountGDT
   },
+  email: (state, email) => {
+    state.email = email || ''
+  },
 }
 
 export const actions = {
   login: ({ dispatch, commit }, data) => {
-    commit('email', data.email)
+    commit('gradidoID', data.gradidoID)
     commit('language', data.language)
-    // commit('username', data.username)
+    commit('username', data.alias)
     commit('firstName', data.firstName)
     commit('lastName', data.lastName)
     commit('newsletterState', data.klickTipp.newsletterState)
@@ -71,8 +74,8 @@ export const actions = {
   },
   logout: ({ commit, state }) => {
     commit('token', null)
-    commit('email', null)
-    // commit('username', '')
+    commit('username', '')
+    commit('gradidoID', null)
     commit('firstName', '')
     commit('lastName', '')
     commit('newsletterState', null)
@@ -81,6 +84,7 @@ export const actions = {
     commit('isAdmin', false)
     commit('hideAmountGDD', false)
     commit('hideAmountGDT', true)
+    commit('email', '')
     localStorage.clear()
   },
 }
@@ -91,12 +95,13 @@ try {
   store = new Vuex.Store({
     plugins: [
       createPersistedState({
+        key: 'gradido-frontend',
         storage: window.localStorage,
       }),
     ],
     state: {
-      email: '',
       language: null,
+      gradidoID: null,
       firstName: '',
       lastName: '',
       // username: '',
@@ -108,6 +113,7 @@ try {
       publisherId: null,
       hideAmountGDD: null,
       hideAmountGDT: null,
+      email: '',
     },
     getters: {},
     // Syncronous mutation of the state
diff --git a/frontend/src/store/store.test.js b/frontend/src/store/store.test.js
index 33fedd562..a6a596209 100644
--- a/frontend/src/store/store.test.js
+++ b/frontend/src/store/store.test.js
@@ -22,16 +22,18 @@ i18n.locale = 'blubb'
 
 const {
   language,
-  email,
+  gradidoID,
   token,
   firstName,
   lastName,
+  username,
   newsletterState,
   publisherId,
   isAdmin,
   hasElopage,
   hideAmountGDD,
   hideAmountGDT,
+  email,
 } = mutations
 const { login, logout } = actions
 
@@ -53,11 +55,11 @@ describe('Vuex store', () => {
       })
     })
 
-    describe('email', () => {
-      it('sets the state of email', () => {
-        const state = { email: 'nobody@knows.tv' }
-        email(state, 'someone@there.is')
-        expect(state.email).toEqual('someone@there.is')
+    describe('gradidoID', () => {
+      it('sets the state of gradidoID', () => {
+        const state = { gradidoID: 'old-id' }
+        gradidoID(state, 'new-id')
+        expect(state.gradidoID).toEqual('new-id')
       })
     })
 
@@ -104,6 +106,14 @@ describe('Vuex store', () => {
       })
     })
 
+    describe('username', () => {
+      it('sets the state of username', () => {
+        const state = { username: null }
+        username(state, 'peter')
+        expect(state.username).toEqual('peter')
+      })
+    })
+
     describe('newsletterState', () => {
       it('sets the state of newsletterState', () => {
         const state = { newsletterState: null }
@@ -157,6 +167,14 @@ describe('Vuex store', () => {
         expect(state.hideAmountGDT).toEqual(true)
       })
     })
+
+    describe('email', () => {
+      it('sets the state of email', () => {
+        const state = { email: '' }
+        email(state, 'peter@luatig.de')
+        expect(state.email).toEqual('peter@luatig.de')
+      })
+    })
   })
 
   describe('actions', () => {
@@ -164,8 +182,9 @@ describe('Vuex store', () => {
       const commit = jest.fn()
       const state = {}
       const commitedData = {
-        email: 'user@example.org',
+        gradidoID: 'my-gradido-id',
         language: 'de',
+        alias: 'peter',
         firstName: 'Peter',
         lastName: 'Lustig',
         klickTipp: {
@@ -180,12 +199,12 @@ describe('Vuex store', () => {
 
       it('calls eleven commits', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenCalledTimes(10)
+        expect(commit).toHaveBeenCalledTimes(11)
       })
 
-      it('commits email', () => {
+      it('commits gradidoID', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(1, 'email', 'user@example.org')
+        expect(commit).toHaveBeenNthCalledWith(1, 'gradidoID', 'my-gradido-id')
       })
 
       it('commits language', () => {
@@ -193,44 +212,49 @@ describe('Vuex store', () => {
         expect(commit).toHaveBeenNthCalledWith(2, 'language', 'de')
       })
 
+      it('commits username', () => {
+        login({ commit, state }, commitedData)
+        expect(commit).toHaveBeenNthCalledWith(3, 'username', 'peter')
+      })
+
       it('commits firstName', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(3, 'firstName', 'Peter')
+        expect(commit).toHaveBeenNthCalledWith(4, 'firstName', 'Peter')
       })
 
       it('commits lastName', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(4, 'lastName', 'Lustig')
+        expect(commit).toHaveBeenNthCalledWith(5, 'lastName', 'Lustig')
       })
 
       it('commits newsletterState', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(5, 'newsletterState', true)
+        expect(commit).toHaveBeenNthCalledWith(6, 'newsletterState', true)
       })
 
       it('commits hasElopage', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(6, 'hasElopage', false)
+        expect(commit).toHaveBeenNthCalledWith(7, 'hasElopage', false)
       })
 
       it('commits publisherId', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(7, 'publisherId', 1234)
+        expect(commit).toHaveBeenNthCalledWith(8, 'publisherId', 1234)
       })
 
       it('commits isAdmin', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(8, 'isAdmin', true)
+        expect(commit).toHaveBeenNthCalledWith(9, 'isAdmin', true)
       })
 
       it('commits hideAmountGDD', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(9, 'hideAmountGDD', false)
+        expect(commit).toHaveBeenNthCalledWith(10, 'hideAmountGDD', false)
       })
 
       it('commits hideAmountGDT', () => {
         login({ commit, state }, commitedData)
-        expect(commit).toHaveBeenNthCalledWith(10, 'hideAmountGDT', true)
+        expect(commit).toHaveBeenNthCalledWith(11, 'hideAmountGDT', true)
       })
     })
 
@@ -238,9 +262,9 @@ describe('Vuex store', () => {
       const commit = jest.fn()
       const state = {}
 
-      it('calls eleven commits', () => {
+      it('calls twelve commits', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenCalledTimes(10)
+        expect(commit).toHaveBeenCalledTimes(12)
       })
 
       it('commits token', () => {
@@ -248,50 +272,61 @@ describe('Vuex store', () => {
         expect(commit).toHaveBeenNthCalledWith(1, 'token', null)
       })
 
-      it('commits email', () => {
+      it('commits username', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(2, 'email', null)
+        expect(commit).toHaveBeenNthCalledWith(2, 'username', '')
+      })
+
+      it('commits gradidoID', () => {
+        logout({ commit, state })
+        expect(commit).toHaveBeenNthCalledWith(3, 'gradidoID', null)
       })
 
       it('commits firstName', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(3, 'firstName', '')
+        expect(commit).toHaveBeenNthCalledWith(4, 'firstName', '')
       })
 
       it('commits lastName', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(4, 'lastName', '')
+        expect(commit).toHaveBeenNthCalledWith(5, 'lastName', '')
       })
 
       it('commits newsletterState', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(5, 'newsletterState', null)
+        expect(commit).toHaveBeenNthCalledWith(6, 'newsletterState', null)
       })
 
       it('commits hasElopage', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(6, 'hasElopage', false)
+        expect(commit).toHaveBeenNthCalledWith(7, 'hasElopage', false)
       })
 
       it('commits publisherId', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(7, 'publisherId', null)
+        expect(commit).toHaveBeenNthCalledWith(8, 'publisherId', null)
       })
 
       it('commits isAdmin', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(8, 'isAdmin', false)
+        expect(commit).toHaveBeenNthCalledWith(9, 'isAdmin', false)
       })
 
       it('commits hideAmountGDD', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(9, 'hideAmountGDD', false)
+        expect(commit).toHaveBeenNthCalledWith(10, 'hideAmountGDD', false)
       })
 
       it('commits hideAmountGDT', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenNthCalledWith(10, 'hideAmountGDT', true)
+        expect(commit).toHaveBeenNthCalledWith(11, 'hideAmountGDT', true)
       })
+
+      it('commits email', () => {
+        logout({ commit, state })
+        expect(commit).toHaveBeenNthCalledWith(12, 'email', '')
+      })
+
       // how to get this working?
       it.skip('calls localStorage.clear()', () => {
         const clearStorageMock = jest.fn()
diff --git a/frontend/src/validation-rules.js b/frontend/src/validation-rules.js
index abb89b59f..adb4dc431 100644
--- a/frontend/src/validation-rules.js
+++ b/frontend/src/validation-rules.js
@@ -1,8 +1,16 @@
 import { configure, extend } from 'vee-validate'
 // eslint-disable-next-line camelcase
 import { required, email, min, max, is_not } from 'vee-validate/dist/rules'
+import { checkUsername } from '@/graphql/queries'
+import { validate as validateUuid, version as versionUuid } from 'uuid'
 
-export const loadAllRules = (i18nCallback) => {
+// taken from vee-validate
+// eslint-disable-next-line no-useless-escape
+const EMAIL_REGEX = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/
+
+const USERNAME_REGEX = /^(?=.{3,20}$)[a-zA-Z0-9]+(?:[_-][a-zA-Z0-9]+?)*$/
+
+export const loadAllRules = (i18nCallback, apollo) => {
   configure({
     defaultMessage: (field, values) => {
       // eslint-disable-next-line @intlify/vue-i18n/no-dynamic-keys
@@ -96,7 +104,7 @@ export const loadAllRules = (i18nCallback) => {
     message: (_, values) => i18nCallback.t('site.signup.one_number', values),
   })
 
-  extend('atLeastEightCharactera', {
+  extend('atLeastEightCharacters', {
     validate(value) {
       return !!value.match(/.{8,}/)
     },
@@ -123,4 +131,45 @@ export const loadAllRules = (i18nCallback) => {
     },
     message: (_, values) => i18nCallback.t('site.signup.dont_match', values),
   })
+
+  extend('usernameAllowedChars', {
+    validate(value) {
+      return !!value.match(/^[a-zA-Z0-9_-]+$/)
+    },
+    message: (_, values) => i18nCallback.t('form.validation.username-allowed-chars', values),
+  })
+
+  extend('usernameHyphens', {
+    validate(value) {
+      return !!value.match(/^[a-zA-Z0-9]+(?:[_-][a-zA-Z0-9]+?)*$/)
+    },
+    message: (_, values) => i18nCallback.t('form.validation.username-hyphens', values),
+  })
+
+  extend('usernameUnique', {
+    validate(value) {
+      if (!value.match(USERNAME_REGEX)) return true
+      return apollo
+        .query({
+          query: checkUsername,
+          variables: { username: value },
+        })
+        .then(({ data }) => {
+          return {
+            valid: data.checkUsername,
+          }
+        })
+    },
+    message: (_, values) => i18nCallback.t('form.validation.username-unique', values),
+  })
+
+  extend('validIdentifier', {
+    validate(value) {
+      const isEmail = !!EMAIL_REGEX.test(value)
+      const isUsername = !!value.match(USERNAME_REGEX)
+      const isGradidoId = validateUuid(value) && versionUuid(value) === 4
+      return isEmail || isUsername || isGradidoId
+    },
+    message: (_, values) => i18nCallback.t('form.validation.valid-identifier', values),
+  })
 }
diff --git a/frontend/test/testSetup.js b/frontend/test/testSetup.js
index 9e844370f..347a6be4a 100644
--- a/frontend/test/testSetup.js
+++ b/frontend/test/testSetup.js
@@ -34,7 +34,7 @@ const i18nMock = {
   n: (value, format) => value,
 }
 
-loadAllRules(i18nMock)
+loadAllRules(i18nMock, { query: jest.fn().mockResolvedValue({ data: { checkUsername: true } }) })
 
 global.localVue = createLocalVue()
 
diff --git a/frontend/vue.config.js b/frontend/vue.config.js
index 573f2a70b..7fb5d5fc2 100644
--- a/frontend/vue.config.js
+++ b/frontend/vue.config.js
@@ -64,5 +64,5 @@ module.exports = {
     // Enable CSS source maps.
     sourceMap: CONFIG.NODE_ENV !== 'production',
   },
-  outputDir: path.resolve(__dirname, './dist'),
+  outputDir: path.resolve(__dirname, './build'),
 }
diff --git a/frontend/yarn.lock b/frontend/yarn.lock
index 7cc8e5fe5..8eff12aaf 100644
--- a/frontend/yarn.lock
+++ b/frontend/yarn.lock
@@ -14176,6 +14176,11 @@ uuid@^8.3.0:
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-8.3.2.tgz#80d5b5ced271bb9af6c445f21a1a04c606cefbe2"
   integrity sha512-+NYs2QeMWy+GWFOEm9xnn6HCDp0l7QBD7ml8zLUmJ+93Q5NF0NocErnwkTkXVFNiX3/fpC6afS8Dhb/gz7R7eg==
 
+uuid@^9.0.0:
+  version "9.0.0"
+  resolved "https://registry.yarnpkg.com/uuid/-/uuid-9.0.0.tgz#592f550650024a38ceb0c562f2f6aa435761efb5"
+  integrity sha512-MXcSTerfPa4uqyzStbRoTgt5XIe3x5+42+q1sDuy3R5MDk66URdLMOZe5aPX/SQd+kuYAh0FdP/pO28IkQyTeg==
+
 v8-compile-cache@^2.0.3, v8-compile-cache@^2.3.0:
   version "2.3.0"
   resolved "https://registry.yarnpkg.com/v8-compile-cache/-/v8-compile-cache-2.3.0.tgz#2de19618c66dc247dcfb6f99338035d8245a2cee"
diff --git a/nginx/gradido.conf b/nginx/gradido.conf
index bfb079d32..403a2766b 100644
--- a/nginx/gradido.conf
+++ b/nginx/gradido.conf
@@ -71,7 +71,7 @@ server {
 
     # TODO this could be a performance optimization
     #location /vue {
-    #    alias /var/www/html/gradido/frontend/dist;
+    #    alias /var/www/html/gradido/frontend/build;
     #    index index.html;
     #
     #    location ~* \.(png)$ {
diff --git a/package.json b/package.json
index 7845d722b..04c8d46c3 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gradido",
-  "version": "1.20.0",
+  "version": "1.21.0",
   "description": "Gradido",
   "main": "index.js",
   "repository": "git@github.com:gradido/gradido.git",