diff --git a/backend/src/auth/JWT.ts b/backend/src/auth/JWT.ts
index 3f9c052f5..a58c2411f 100644
--- a/backend/src/auth/JWT.ts
+++ b/backend/src/auth/JWT.ts
@@ -1,4 +1,4 @@
-import jwt from 'jsonwebtoken'
+import { verify, sign } from 'jsonwebtoken'
 import CONFIG from '@/config/'
 import { CustomJwtPayload } from './CustomJwtPayload'
 import LogError from '@/server/LogError'
@@ -6,14 +6,14 @@ import LogError from '@/server/LogError'
 export const decode = (token: string): CustomJwtPayload | null => {
   if (!token) throw new LogError('401 Unauthorized')
   try {
-    return <CustomJwtPayload>jwt.verify(token, CONFIG.JWT_SECRET)
+    return <CustomJwtPayload>verify(token, CONFIG.JWT_SECRET)
   } catch (err) {
     return null
   }
 }
 
 export const encode = (gradidoID: string): string => {
-  const token = jwt.sign({ gradidoID }, CONFIG.JWT_SECRET, {
+  const token = sign({ gradidoID }, CONFIG.JWT_SECRET, {
     expiresIn: CONFIG.JWT_EXPIRES_IN,
   })
   return token
diff --git a/backend/src/config/index.ts b/backend/src/config/index.ts
index 27b51b47d..13f2a7663 100644
--- a/backend/src/config/index.ts
+++ b/backend/src/config/index.ts
@@ -1,7 +1,7 @@
 // ATTENTION: DO NOT PUT ANY SECRETS IN HERE (or the .env)
 
 import dotenv from 'dotenv'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 dotenv.config()
 
 Decimal.set({
diff --git a/backend/src/emails/sendEmailVariants.test.ts b/backend/src/emails/sendEmailVariants.test.ts
index 21c10bdad..24e5b0ebd 100644
--- a/backend/src/emails/sendEmailVariants.test.ts
+++ b/backend/src/emails/sendEmailVariants.test.ts
@@ -3,7 +3,7 @@
 /* eslint-disable @typescript-eslint/no-unsafe-return */
 /* eslint-disable @typescript-eslint/no-unsafe-call */
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { testEnvironment } from '@test/helpers'
 import { logger, i18n as localization } from '@test/testSetup'
 import CONFIG from '@/config'
diff --git a/backend/src/emails/sendEmailVariants.ts b/backend/src/emails/sendEmailVariants.ts
index 4e3881829..c2a2dc366 100644
--- a/backend/src/emails/sendEmailVariants.ts
+++ b/backend/src/emails/sendEmailVariants.ts
@@ -1,4 +1,4 @@
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import CONFIG from '@/config'
 import { decimalSeparatorByLanguage } from '@/util/utilities'
 import { sendEmailTranslated } from './sendEmailTranslated'
diff --git a/backend/src/event/Event.ts b/backend/src/event/Event.ts
index 8e65d85f2..f771bdee3 100644
--- a/backend/src/event/Event.ts
+++ b/backend/src/event/Event.ts
@@ -1,5 +1,5 @@
 import { EventProtocol as DbEvent } from '@entity/EventProtocol'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { EventProtocolType } from './EventProtocolType'
 
 export const Event = (
diff --git a/backend/src/graphql/arg/AdminCreateContributionArgs.ts b/backend/src/graphql/arg/AdminCreateContributionArgs.ts
index b09edea32..6259e672e 100644
--- a/backend/src/graphql/arg/AdminCreateContributionArgs.ts
+++ b/backend/src/graphql/arg/AdminCreateContributionArgs.ts
@@ -1,5 +1,5 @@
 import { ArgsType, Field, InputType } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @InputType()
 @ArgsType()
diff --git a/backend/src/graphql/arg/AdminUpdateContributionArgs.ts b/backend/src/graphql/arg/AdminUpdateContributionArgs.ts
index 392365b38..3b10acf1a 100644
--- a/backend/src/graphql/arg/AdminUpdateContributionArgs.ts
+++ b/backend/src/graphql/arg/AdminUpdateContributionArgs.ts
@@ -1,5 +1,5 @@
 import { ArgsType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ArgsType()
 export default class AdminUpdateContributionArgs {
diff --git a/backend/src/graphql/arg/ContributionArgs.ts b/backend/src/graphql/arg/ContributionArgs.ts
index 2fa1c5ced..dc4285e4d 100644
--- a/backend/src/graphql/arg/ContributionArgs.ts
+++ b/backend/src/graphql/arg/ContributionArgs.ts
@@ -1,5 +1,5 @@
 import { ArgsType, Field, InputType } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @InputType()
 @ArgsType()
diff --git a/backend/src/graphql/arg/ContributionLinkArgs.ts b/backend/src/graphql/arg/ContributionLinkArgs.ts
index cf0465501..fac1eacc1 100644
--- a/backend/src/graphql/arg/ContributionLinkArgs.ts
+++ b/backend/src/graphql/arg/ContributionLinkArgs.ts
@@ -1,5 +1,5 @@
 import { ArgsType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ArgsType()
 export default class ContributionLinkArgs {
diff --git a/backend/src/graphql/arg/TransactionLinkArgs.ts b/backend/src/graphql/arg/TransactionLinkArgs.ts
index 553efcfbe..6c1c4654a 100644
--- a/backend/src/graphql/arg/TransactionLinkArgs.ts
+++ b/backend/src/graphql/arg/TransactionLinkArgs.ts
@@ -1,5 +1,5 @@
 import { ArgsType, Field } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ArgsType()
 export default class TransactionLinkArgs {
diff --git a/backend/src/graphql/arg/TransactionSendArgs.ts b/backend/src/graphql/arg/TransactionSendArgs.ts
index e75921383..c0faff850 100644
--- a/backend/src/graphql/arg/TransactionSendArgs.ts
+++ b/backend/src/graphql/arg/TransactionSendArgs.ts
@@ -1,5 +1,5 @@
 import { ArgsType, Field } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ArgsType()
 export default class TransactionSendArgs {
diff --git a/backend/src/graphql/model/AdminUpdateContribution.ts b/backend/src/graphql/model/AdminUpdateContribution.ts
index e824975a4..d5cd4fc7f 100644
--- a/backend/src/graphql/model/AdminUpdateContribution.ts
+++ b/backend/src/graphql/model/AdminUpdateContribution.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ObjectType()
 export class AdminUpdateContribution {
diff --git a/backend/src/graphql/model/Balance.ts b/backend/src/graphql/model/Balance.ts
index 9b54f6987..d68237db9 100644
--- a/backend/src/graphql/model/Balance.ts
+++ b/backend/src/graphql/model/Balance.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int, Float } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ObjectType()
 export class Balance {
diff --git a/backend/src/graphql/model/CommunityStatistics.ts b/backend/src/graphql/model/CommunityStatistics.ts
index 4864b630d..1fb1ded46 100644
--- a/backend/src/graphql/model/CommunityStatistics.ts
+++ b/backend/src/graphql/model/CommunityStatistics.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ObjectType()
 export class DynamicStatisticsFields {
diff --git a/backend/src/graphql/model/Contribution.ts b/backend/src/graphql/model/Contribution.ts
index a683534af..a83adef4b 100644
--- a/backend/src/graphql/model/Contribution.ts
+++ b/backend/src/graphql/model/Contribution.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Contribution as dbContribution } from '@entity/Contribution'
 import { User } from '@entity/User'
 
diff --git a/backend/src/graphql/model/ContributionLink.ts b/backend/src/graphql/model/ContributionLink.ts
index 7a06f8dff..13ae31692 100644
--- a/backend/src/graphql/model/ContributionLink.ts
+++ b/backend/src/graphql/model/ContributionLink.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { ContributionLink as dbContributionLink } from '@entity/ContributionLink'
 import CONFIG from '@/config'
 
diff --git a/backend/src/graphql/model/Decay.ts b/backend/src/graphql/model/Decay.ts
index f59a21249..3e8412dfa 100644
--- a/backend/src/graphql/model/Decay.ts
+++ b/backend/src/graphql/model/Decay.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 interface DecayInterface {
   balance: Decimal
diff --git a/backend/src/graphql/model/OpenCreation.ts b/backend/src/graphql/model/OpenCreation.ts
index 9ef08fd4a..ed9ef731e 100644
--- a/backend/src/graphql/model/OpenCreation.ts
+++ b/backend/src/graphql/model/OpenCreation.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @ObjectType()
 export class OpenCreation {
diff --git a/backend/src/graphql/model/Transaction.ts b/backend/src/graphql/model/Transaction.ts
index 96b80f9a0..d24c28f2f 100644
--- a/backend/src/graphql/model/Transaction.ts
+++ b/backend/src/graphql/model/Transaction.ts
@@ -1,7 +1,7 @@
 import { ObjectType, Field, Int } from 'type-graphql'
 import { Decay } from './Decay'
 import { Transaction as dbTransaction } from '@entity/Transaction'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { TransactionTypeId } from '@enum/TransactionTypeId'
 import { User } from './User'
 
diff --git a/backend/src/graphql/model/TransactionLink.ts b/backend/src/graphql/model/TransactionLink.ts
index b0a8ab184..ddd22f36f 100644
--- a/backend/src/graphql/model/TransactionLink.ts
+++ b/backend/src/graphql/model/TransactionLink.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { TransactionLink as dbTransactionLink } from '@entity/TransactionLink'
 import { User } from './User'
 import CONFIG from '@/config'
diff --git a/backend/src/graphql/model/UnconfirmedContribution.ts b/backend/src/graphql/model/UnconfirmedContribution.ts
index 75112ecf5..439f70a16 100644
--- a/backend/src/graphql/model/UnconfirmedContribution.ts
+++ b/backend/src/graphql/model/UnconfirmedContribution.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Contribution } from '@entity/Contribution'
 import { User } from '@entity/User'
 
diff --git a/backend/src/graphql/model/UserAdmin.ts b/backend/src/graphql/model/UserAdmin.ts
index e7330471b..84512d812 100644
--- a/backend/src/graphql/model/UserAdmin.ts
+++ b/backend/src/graphql/model/UserAdmin.ts
@@ -1,5 +1,5 @@
 import { ObjectType, Field, Int } from 'type-graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { User } from '@entity/User'
 
 @ObjectType()
diff --git a/backend/src/graphql/resolver/BalanceResolver.ts b/backend/src/graphql/resolver/BalanceResolver.ts
index 18aed5ae6..3a090e551 100644
--- a/backend/src/graphql/resolver/BalanceResolver.ts
+++ b/backend/src/graphql/resolver/BalanceResolver.ts
@@ -1,5 +1,5 @@
 /* eslint-disable @typescript-eslint/restrict-template-expressions */
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Resolver, Query, Ctx, Authorized } from 'type-graphql'
 import { getCustomRepository } from '@dbTools/typeorm'
 
diff --git a/backend/src/graphql/resolver/ContributionLinkResolver.test.ts b/backend/src/graphql/resolver/ContributionLinkResolver.test.ts
index 606bce109..aae42c44b 100644
--- a/backend/src/graphql/resolver/ContributionLinkResolver.test.ts
+++ b/backend/src/graphql/resolver/ContributionLinkResolver.test.ts
@@ -4,7 +4,7 @@
 /* eslint-disable @typescript-eslint/no-unsafe-member-access */
 /* eslint-disable @typescript-eslint/no-explicit-any */
 
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { logger } from '@test/testSetup'
 import { GraphQLError } from 'graphql'
 import {
diff --git a/backend/src/graphql/resolver/ContributionLinkResolver.ts b/backend/src/graphql/resolver/ContributionLinkResolver.ts
index cccf47399..f7a47ab01 100644
--- a/backend/src/graphql/resolver/ContributionLinkResolver.ts
+++ b/backend/src/graphql/resolver/ContributionLinkResolver.ts
@@ -1,4 +1,4 @@
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Resolver, Args, Arg, Authorized, Mutation, Query, Int } from 'type-graphql'
 import { MoreThan, IsNull } from '@dbTools/typeorm'
 
diff --git a/backend/src/graphql/resolver/ContributionResolver.test.ts b/backend/src/graphql/resolver/ContributionResolver.test.ts
index a15c64e85..c478902e6 100644
--- a/backend/src/graphql/resolver/ContributionResolver.test.ts
+++ b/backend/src/graphql/resolver/ContributionResolver.test.ts
@@ -6,7 +6,7 @@
 /* eslint-disable @typescript-eslint/no-explicit-any */
 /* eslint-disable @typescript-eslint/explicit-module-boundary-types */
 
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { bibiBloxberg } from '@/seeds/users/bibi-bloxberg'
 import { bobBaumeister } from '@/seeds/users/bob-baumeister'
 import { stephenHawking } from '@/seeds/users/stephen-hawking'
diff --git a/backend/src/graphql/resolver/ContributionResolver.ts b/backend/src/graphql/resolver/ContributionResolver.ts
index a91b53300..6c895b339 100644
--- a/backend/src/graphql/resolver/ContributionResolver.ts
+++ b/backend/src/graphql/resolver/ContributionResolver.ts
@@ -1,5 +1,5 @@
 /* eslint-disable @typescript-eslint/restrict-template-expressions */
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Arg, Args, Authorized, Ctx, Int, Mutation, Query, Resolver } from 'type-graphql'
 import { IsNull, getConnection } from '@dbTools/typeorm'
 
diff --git a/backend/src/graphql/resolver/StatisticsResolver.ts b/backend/src/graphql/resolver/StatisticsResolver.ts
index 38d0000cb..d5ae9503c 100644
--- a/backend/src/graphql/resolver/StatisticsResolver.ts
+++ b/backend/src/graphql/resolver/StatisticsResolver.ts
@@ -1,6 +1,6 @@
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
 /* eslint-disable @typescript-eslint/no-unsafe-return */
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Resolver, Query, Authorized, FieldResolver } from 'type-graphql'
 import { getConnection } from '@dbTools/typeorm'
 
diff --git a/backend/src/graphql/resolver/TransactionLinkResolver.test.ts b/backend/src/graphql/resolver/TransactionLinkResolver.test.ts
index 35d3f42f6..b3e4df80d 100644
--- a/backend/src/graphql/resolver/TransactionLinkResolver.test.ts
+++ b/backend/src/graphql/resolver/TransactionLinkResolver.test.ts
@@ -27,7 +27,7 @@ import { listTransactionLinksAdmin } from '@/seeds/graphql/queries'
 import { ContributionLink as DbContributionLink } from '@entity/ContributionLink'
 import { User } from '@entity/User'
 import { UnconfirmedContribution } from '@model/UnconfirmedContribution'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { GraphQLError } from 'graphql'
 import { TRANSACTIONS_LOCK } from '@/util/TRANSACTIONS_LOCK'
 import { logger } from '@test/testSetup'
diff --git a/backend/src/graphql/resolver/TransactionLinkResolver.ts b/backend/src/graphql/resolver/TransactionLinkResolver.ts
index d6e8e09ae..293f7c6f2 100644
--- a/backend/src/graphql/resolver/TransactionLinkResolver.ts
+++ b/backend/src/graphql/resolver/TransactionLinkResolver.ts
@@ -1,5 +1,5 @@
 import { randomBytes } from 'crypto'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 import { getConnection } from '@dbTools/typeorm'
 
diff --git a/backend/src/graphql/resolver/TransactionResolver.test.ts b/backend/src/graphql/resolver/TransactionResolver.test.ts
index c660a72da..31fc41ed1 100644
--- a/backend/src/graphql/resolver/TransactionResolver.test.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.test.ts
@@ -5,7 +5,7 @@
 /* eslint-disable @typescript-eslint/no-explicit-any */
 /* eslint-disable @typescript-eslint/explicit-module-boundary-types */
 
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { EventProtocolType } from '@/event/EventProtocolType'
 import { userFactory } from '@/seeds/factory/user'
 import {
diff --git a/backend/src/graphql/resolver/TransactionResolver.ts b/backend/src/graphql/resolver/TransactionResolver.ts
index a11c5b377..83d663f93 100644
--- a/backend/src/graphql/resolver/TransactionResolver.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.ts
@@ -2,7 +2,7 @@
 /* eslint-disable new-cap */
 /* eslint-disable @typescript-eslint/no-non-null-assertion */
 
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Resolver, Query, Args, Authorized, Ctx, Mutation } from 'type-graphql'
 import { getCustomRepository, getConnection, In } from '@dbTools/typeorm'
 
diff --git a/backend/src/graphql/resolver/const/const.ts b/backend/src/graphql/resolver/const/const.ts
index e4eb9a13b..b97694221 100644
--- a/backend/src/graphql/resolver/const/const.ts
+++ b/backend/src/graphql/resolver/const/const.ts
@@ -1,4 +1,4 @@
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 export const MAX_CREATION_AMOUNT = new Decimal(1000)
 export const FULL_CREATION_AVAILABLE = [
diff --git a/backend/src/graphql/resolver/semaphore.test.ts b/backend/src/graphql/resolver/semaphore.test.ts
index 1ce133fba..a770638fb 100644
--- a/backend/src/graphql/resolver/semaphore.test.ts
+++ b/backend/src/graphql/resolver/semaphore.test.ts
@@ -4,7 +4,7 @@
 /* eslint-disable @typescript-eslint/restrict-template-expressions */
 /* eslint-disable @typescript-eslint/no-explicit-any */
 
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { userFactory } from '@/seeds/factory/user'
 import { bibiBloxberg } from '@/seeds/users/bibi-bloxberg'
 import { bobBaumeister } from '@/seeds/users/bob-baumeister'
diff --git a/backend/src/graphql/resolver/util/creations.ts b/backend/src/graphql/resolver/util/creations.ts
index 33b48a3a3..e7a3cc965 100644
--- a/backend/src/graphql/resolver/util/creations.ts
+++ b/backend/src/graphql/resolver/util/creations.ts
@@ -4,7 +4,7 @@ import LogError from '@/server/LogError'
 import { backendLogger as logger } from '@/server/logger'
 import { getConnection } from '@dbTools/typeorm'
 import { Contribution } from '@entity/Contribution'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { FULL_CREATION_AVAILABLE, MAX_CREATION_AMOUNT } from '../const/const'
 
 interface CreationMap {
diff --git a/backend/src/graphql/scalar/Decimal.ts b/backend/src/graphql/scalar/Decimal.ts
index da5a99e0c..0f259343c 100644
--- a/backend/src/graphql/scalar/Decimal.ts
+++ b/backend/src/graphql/scalar/Decimal.ts
@@ -1,5 +1,5 @@
 import { GraphQLScalarType, Kind } from 'graphql'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 export default new GraphQLScalarType({
   name: 'Decimal',
diff --git a/backend/src/graphql/schema.ts b/backend/src/graphql/schema.ts
index f14f45efa..3f12a5d8c 100644
--- a/backend/src/graphql/schema.ts
+++ b/backend/src/graphql/schema.ts
@@ -4,7 +4,7 @@ import path from 'path'
 
 import isAuthorized from './directive/isAuthorized'
 import DecimalScalar from './scalar/Decimal'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 const schema = async (): Promise<GraphQLSchema> => {
   return buildSchema({
diff --git a/backend/src/seeds/graphql/mutations.ts b/backend/src/seeds/graphql/mutations.ts
index 69d6d16d8..0851c0adc 100644
--- a/backend/src/seeds/graphql/mutations.ts
+++ b/backend/src/seeds/graphql/mutations.ts
@@ -1,4 +1,4 @@
-import gql from 'graphql-tag'
+import { gql } from 'graphql-tag'
 
 export const subscribeNewsletter = gql`
   mutation ($email: String!, $language: String!) {
diff --git a/backend/src/seeds/graphql/queries.ts b/backend/src/seeds/graphql/queries.ts
index 299a0103d..49d9e7cbf 100644
--- a/backend/src/seeds/graphql/queries.ts
+++ b/backend/src/seeds/graphql/queries.ts
@@ -1,4 +1,4 @@
-import gql from 'graphql-tag'
+import { gql } from 'graphql-tag'
 
 export const verifyLogin = gql`
   query {
diff --git a/backend/src/server/context.ts b/backend/src/server/context.ts
index 32a765777..5727e2707 100644
--- a/backend/src/server/context.ts
+++ b/backend/src/server/context.ts
@@ -1,7 +1,7 @@
 import { Role } from '@/auth/Role'
 import { User as dbUser } from '@entity/User'
 import { Transaction as dbTransaction } from '@entity/Transaction'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { ExpressContext } from 'apollo-server-express'
 import LogError from './LogError'
 
diff --git a/backend/src/server/createServer.ts b/backend/src/server/createServer.ts
index 0c5009b6f..5b3be4998 100644
--- a/backend/src/server/createServer.ts
+++ b/backend/src/server/createServer.ts
@@ -4,7 +4,7 @@
 import 'reflect-metadata'
 
 import { ApolloServer } from 'apollo-server-express'
-import express, { Express } from 'express'
+import express, { Express, json, urlencoded } from 'express'
 
 // database
 import connection from '@/typeorm/connection'
@@ -66,9 +66,9 @@ const createServer = async (
   app.use(cors)
 
   // bodyparser json
-  app.use(express.json())
+  app.use(json())
   // bodyparser urlencoded for elopage
-  app.use(express.urlencoded({ extended: true }))
+  app.use(urlencoded({ extended: true }))
 
   // i18n
   app.use(localization.init)
diff --git a/backend/src/server/logger.ts b/backend/src/server/logger.ts
index 5cfa94285..e72e425a2 100644
--- a/backend/src/server/logger.ts
+++ b/backend/src/server/logger.ts
@@ -1,6 +1,6 @@
 /* eslint-disable @typescript-eslint/no-unsafe-member-access */
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
-import log4js from 'log4js'
+import { configure, getLogger } from 'log4js'
 import CONFIG from '@/config'
 
 import { readFileSync } from 'fs'
@@ -10,11 +10,11 @@ const options = JSON.parse(readFileSync(CONFIG.LOG4JS_CONFIG, 'utf-8'))
 options.categories.backend.level = CONFIG.LOG_LEVEL
 options.categories.apollo.level = CONFIG.LOG_LEVEL
 
-log4js.configure(options)
+configure(options)
 
-const apolloLogger = log4js.getLogger('apollo')
-const backendLogger = log4js.getLogger('backend')
-const klickTippLogger = log4js.getLogger('klicktipp')
+const apolloLogger = getLogger('apollo')
+const backendLogger = getLogger('backend')
+const klickTippLogger = getLogger('klicktipp')
 
 backendLogger.addContext('user', 'unknown')
 
diff --git a/backend/src/typeorm/repository/TransactionLink.ts b/backend/src/typeorm/repository/TransactionLink.ts
index 7df1fd465..d2458b386 100644
--- a/backend/src/typeorm/repository/TransactionLink.ts
+++ b/backend/src/typeorm/repository/TransactionLink.ts
@@ -1,7 +1,7 @@
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
 import { Repository, EntityRepository } from '@dbTools/typeorm'
 import { TransactionLink as dbTransactionLink } from '@entity/TransactionLink'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 @EntityRepository(dbTransactionLink)
 export class TransactionLinkRepository extends Repository<dbTransactionLink> {
diff --git a/backend/src/util/decay.test.ts b/backend/src/util/decay.test.ts
index 0e7b02f56..d07ee6569 100644
--- a/backend/src/util/decay.test.ts
+++ b/backend/src/util/decay.test.ts
@@ -1,4 +1,4 @@
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import 'reflect-metadata' // This might be wise to load in a test setup file
 import { decayFormula, calculateDecay } from './decay'
 
diff --git a/backend/src/util/decay.ts b/backend/src/util/decay.ts
index 641654756..d35eb83a4 100644
--- a/backend/src/util/decay.ts
+++ b/backend/src/util/decay.ts
@@ -1,4 +1,4 @@
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import CONFIG from '@/config'
 import { Decay } from '@model/Decay'
 import LogError from '@/server/LogError'
diff --git a/backend/src/util/utilities.ts b/backend/src/util/utilities.ts
index fa8e82d9e..2cf53f1e4 100644
--- a/backend/src/util/utilities.ts
+++ b/backend/src/util/utilities.ts
@@ -1,4 +1,4 @@
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import i18n from 'i18n'
 
 export const objectValuesToArray = (obj: { [x: string]: string }): Array<string> => {
diff --git a/backend/src/util/validate.ts b/backend/src/util/validate.ts
index 482e9eb50..ff4b17841 100644
--- a/backend/src/util/validate.ts
+++ b/backend/src/util/validate.ts
@@ -1,5 +1,5 @@
 import { calculateDecay } from './decay'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 import { Decay } from '@model/Decay'
 import { getCustomRepository } from '@dbTools/typeorm'
 import { TransactionLinkRepository } from '@repository/TransactionLink'
diff --git a/backend/src/util/virtualTransactions.ts b/backend/src/util/virtualTransactions.ts
index b02f87ee5..2ee899009 100644
--- a/backend/src/util/virtualTransactions.ts
+++ b/backend/src/util/virtualTransactions.ts
@@ -5,7 +5,7 @@ import { Transaction as dbTransaction } from '@entity/Transaction'
 import { TransactionTypeId } from '@enum/TransactionTypeId'
 import { calculateDecay } from './decay'
 import { User } from '@model/User'
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 const defaultModelFunctions = {
   hasId: function (): boolean {
diff --git a/backend/test/extensions.ts b/backend/test/extensions.ts
index 26fb11510..359597f4a 100644
--- a/backend/test/extensions.ts
+++ b/backend/test/extensions.ts
@@ -3,7 +3,7 @@
 /* eslint-disable @typescript-eslint/restrict-template-expressions */
 /* eslint-disable @typescript-eslint/no-empty-interface */
 
-import Decimal from 'decimal.js-light'
+import { Decimal } from 'decimal.js-light'
 
 expect.extend({
   decimalEqual(received, value) {