diff --git a/backend/src/entities/assignments/submission.entity.ts b/backend/src/entities/assignments/submission.entity.ts
index fbaa2791..e4330e0d 100644
--- a/backend/src/entities/assignments/submission.entity.ts
+++ b/backend/src/entities/assignments/submission.entity.ts
@@ -16,7 +16,7 @@ export class Submission {
     learningObjectLanguage!: Language;
 
     @PrimaryKey({ type: 'numeric' })
-    learningObjectVersion: number = 1;
+    learningObjectVersion = 1;
 
     @PrimaryKey({ type: 'integer', autoincrement: true })
     submissionNumber?: number;
diff --git a/backend/src/entities/content/learning-object.entity.ts b/backend/src/entities/content/learning-object.entity.ts
index a0da9d7b..e352a10a 100644
--- a/backend/src/entities/content/learning-object.entity.ts
+++ b/backend/src/entities/content/learning-object.entity.ts
@@ -20,7 +20,7 @@ export class LearningObject {
     language!: Language;
 
     @PrimaryKey({ type: 'number' })
-    version: number = 1;
+    version = 1;
 
     @Property({ type: 'uuid', unique: true })
     uuid = v4();
@@ -46,7 +46,7 @@ export class LearningObject {
     targetAges?: number[] = [];
 
     @Property({ type: 'bool' })
-    teacherExclusive: boolean = false;
+    teacherExclusive = false;
 
     @Property({ type: 'array' })
     skosConcepts: string[] = [];
@@ -58,10 +58,10 @@ export class LearningObject {
     educationalGoals: EducationalGoal[] = [];
 
     @Property({ type: 'string' })
-    copyright: string = '';
+    copyright = '';
 
     @Property({ type: 'string' })
-    license: string = '';
+    license = '';
 
     @Property({ type: 'smallint', nullable: true })
     difficulty?: number;
@@ -75,7 +75,7 @@ export class LearningObject {
     returnValue!: ReturnValue;
 
     @Property({ type: 'bool' })
-    available: boolean = true;
+    available = true;
 
     @Property({ type: 'string', nullable: true })
     contentLocation?: string;
diff --git a/backend/src/entities/questions/question.entity.ts b/backend/src/entities/questions/question.entity.ts
index 058ba6b3..09e3cd46 100644
--- a/backend/src/entities/questions/question.entity.ts
+++ b/backend/src/entities/questions/question.entity.ts
@@ -15,7 +15,7 @@ export class Question {
     learningObjectLanguage!: Language;
 
     @PrimaryKey({ type: 'number' })
-    learningObjectVersion: number = 1;
+    learningObjectVersion = 1;
 
     @PrimaryKey({ type: 'integer', autoincrement: true })
     sequenceNumber?: number;
diff --git a/backend/src/entities/users/user.entity.ts b/backend/src/entities/users/user.entity.ts
index 1f35a0f8..15637110 100644
--- a/backend/src/entities/users/user.entity.ts
+++ b/backend/src/entities/users/user.entity.ts
@@ -6,8 +6,8 @@ export abstract class User {
     username!: string;
 
     @Property()
-    firstName: string = '';
+    firstName = '';
 
     @Property()
-    lastName: string = '';
+    lastName = '';
 }
diff --git a/backend/src/exceptions/badRequestException.ts b/backend/src/exceptions/badRequestException.ts
index 7249fcc8..ae672755 100644
--- a/backend/src/exceptions/badRequestException.ts
+++ b/backend/src/exceptions/badRequestException.ts
@@ -5,7 +5,7 @@ import { HttpException } from './httpException.js';
  */
 
 export class BadRequestException extends HttpException {
-    constructor(message: string = 'Bad Request') {
+    constructor(message = 'Bad Request') {
         super(400, message);
     }
 }
diff --git a/backend/src/exceptions/forbiddenException.ts b/backend/src/exceptions/forbiddenException.ts
index f452e390..9c58c43d 100644
--- a/backend/src/exceptions/forbiddenException.ts
+++ b/backend/src/exceptions/forbiddenException.ts
@@ -4,7 +4,7 @@ import { HttpException } from './httpException.js';
  * Exception for HTTP 403 Forbidden
  */
 export class ForbiddenException extends HttpException {
-    constructor(message: string = 'Forbidden') {
+    constructor(message = 'Forbidden') {
         super(403, message);
     }
 }
diff --git a/backend/src/exceptions/notFoundException.ts b/backend/src/exceptions/notFoundException.ts
index b5c6a916..6f682410 100644
--- a/backend/src/exceptions/notFoundException.ts
+++ b/backend/src/exceptions/notFoundException.ts
@@ -4,7 +4,7 @@ import { HttpException } from './httpException.js';
  * Exception for HTTP 404 Not Found
  */
 export class NotFoundException extends HttpException {
-    constructor(message: string = 'Not Found') {
+    constructor(message = 'Not Found') {
         super(404, message);
     }
 }
diff --git a/backend/src/exceptions/unauthorizedException.ts b/backend/src/exceptions/unauthorizedException.ts
index 51ce04d4..a171084e 100644
--- a/backend/src/exceptions/unauthorizedException.ts
+++ b/backend/src/exceptions/unauthorizedException.ts
@@ -4,7 +4,7 @@ import { HttpException } from './httpException.js';
  * Exception for HTTP 401 Unauthorized
  */
 export class UnauthorizedException extends HttpException {
-    constructor(message: string = 'Unauthorized') {
+    constructor(message = 'Unauthorized') {
         super(401, message);
     }
 }
diff --git a/backend/src/mikro-orm.config.ts b/backend/src/mikro-orm.config.ts
index ffa12c82..86ceafe5 100644
--- a/backend/src/mikro-orm.config.ts
+++ b/backend/src/mikro-orm.config.ts
@@ -43,7 +43,7 @@ const entities = [
     Question,
 ];
 
-function config(testingMode: boolean = false): Options {
+function config(testingMode = false): Options {
     if (testingMode) {
         return {
             driver: SqliteDriver,
diff --git a/backend/src/orm.ts b/backend/src/orm.ts
index 419d5990..3e6e26c8 100644
--- a/backend/src/orm.ts
+++ b/backend/src/orm.ts
@@ -4,7 +4,7 @@ import { envVars, getEnvVar } from './util/envVars.js';
 import { getLogger, Logger } from './logging/initalize.js';
 
 let orm: MikroORM | undefined;
-export async function initORM(testingMode: boolean = false): Promise<void> {
+export async function initORM(testingMode = false): Promise<void> {
     const logger: Logger = getLogger();
 
     logger.info('Initializing ORM');
diff --git a/backend/src/sqlite-autoincrement-workaround.ts b/backend/src/sqlite-autoincrement-workaround.ts
index 29d02ffc..e45a5141 100644
--- a/backend/src/sqlite-autoincrement-workaround.ts
+++ b/backend/src/sqlite-autoincrement-workaround.ts
@@ -14,7 +14,7 @@ import { EntityProperty, EventArgs, EventSubscriber } from '@mikro-orm/core';
  *   the sequence number will not be filled in.
  */
 export class SqliteAutoincrementSubscriber implements EventSubscriber {
-    private sequenceNumbersForEntityType: Map<string, number> = new Map();
+    private sequenceNumbersForEntityType = new Map<string, number>();
 
     /**
      * When an entity with an autoincremented property which is part of the composite private key is created,
diff --git a/backend/src/util/envVars.ts b/backend/src/util/envVars.ts
index 09287788..61f6289c 100644
--- a/backend/src/util/envVars.ts
+++ b/backend/src/util/envVars.ts
@@ -11,7 +11,7 @@ interface EnvVar {
     defaultValue?: number | string | boolean;
 }
 
-export const envVars: { [key: string]: EnvVar } = {
+export const envVars: Record<string, EnvVar> = {
     Port: { key: PREFIX + 'PORT', defaultValue: 3000 },
     DbHost: { key: DB_PREFIX + 'HOST', required: true },
     DbPort: { key: DB_PREFIX + 'PORT', defaultValue: 5432 },
diff --git a/backend/tests/test-assets/learning-objects/learning-object-example.d.ts b/backend/tests/test-assets/learning-objects/learning-object-example.d.ts
index 5053ca75..3054644f 100644
--- a/backend/tests/test-assets/learning-objects/learning-object-example.d.ts
+++ b/backend/tests/test-assets/learning-objects/learning-object-example.d.ts
@@ -3,6 +3,6 @@ import { Attachment } from '../../../src/entities/content/attachment.entity';
 
 interface LearningObjectExample {
     createLearningObject: () => LearningObject;
-    createAttachment: { [key: string]: (owner: LearningObject) => Attachment };
+    createAttachment: Record<string, (owner: LearningObject) => Attachment>;
     getHTMLRendering: () => string;
 }
diff --git a/eslint.config.ts b/eslint.config.ts
index a262f812..0a08619f 100644
--- a/eslint.config.ts
+++ b/eslint.config.ts
@@ -82,6 +82,10 @@ export default [
             // 'no-empty-function': 'off',
             '@typescript-eslint/no-empty-function': 'error',
 
+            '@typescript-eslint/no-for-in-array': 'error',
+
+            '@typescript-eslint/no-inferrable-types': 'warn',
+
             'no-loop-func': 'off',
             '@typescript-eslint/no-loop-func': 'error',