diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index da2552cb8a207cadeef72c65c5df74212c917413..7b683904d1ededd58c57ad4cc9277b0dca4aa694 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -21,7 +21,7 @@ tslint:
     - npm install @angular/core
     - npm install typescript
     - npm install rxjs
-    - node_modules/tslint/bin/tslint -p ./tsconfig.json -c ./tslint.json ./src/**/*.ts
+    - node_modules/tslint/bin/tslint -p ./tsconfig.json -c ./tslint.json --project
 
 ngbuild:
   stage: build
diff --git a/src/app/components/creator/content-creator/content-creator.component.ts b/src/app/components/creator/content-creator/content-creator.component.ts
index c714e60b94ae35cea50abf2df1a15f5bc5606856..c3915f07b0c8521a9372153f856172b4394f2f0e 100644
--- a/src/app/components/creator/content-creator/content-creator.component.ts
+++ b/src/app/components/creator/content-creator/content-creator.component.ts
@@ -1,6 +1,6 @@
 import { Component, Input, OnInit } from '@angular/core';
 import { ContentText } from '../../../models/content-text';
-import { FormControl } from '@angular/forms';;
+import { FormControl } from '@angular/forms';
 import { Room } from '../../../models/room';
 import { TranslateService } from '@ngx-translate/core';
 
diff --git a/src/app/components/home/_dialogs/user-activation/user-activation.component.ts b/src/app/components/home/_dialogs/user-activation/user-activation.component.ts
index f0f71df0deb6b774d711a2c02a39686215c08054..74629868e8f34cb20109be64f5c71f2916e4c0bf 100644
--- a/src/app/components/home/_dialogs/user-activation/user-activation.component.ts
+++ b/src/app/components/home/_dialogs/user-activation/user-activation.component.ts
@@ -1,8 +1,8 @@
 import { Component, Inject, OnInit } from '@angular/core';
 import { NotificationService } from '../../../../services/util/notification.service';
 import { UserService } from '../../../../services/http/user.service';
-import { FormControl, Validators} from '@angular/forms';
-import { MAT_DIALOG_DATA, MatDialogRef} from '@angular/material';
+import { FormControl, Validators } from '@angular/forms';
+import { MAT_DIALOG_DATA, MatDialogRef } from '@angular/material';
 import { TranslateService } from '@ngx-translate/core';
 
 @Component({
@@ -31,7 +31,7 @@ export class UserActivationComponent implements OnInit {
 
     this.userService.activate(this.data.name.trim(), activationKey).subscribe(
       ret => {
-        this.dialogRef.close({success: true});
+        this.dialogRef.close({ success: true });
       },
       err => {
         this.translationService.get('login.activation-key-incorrect').subscribe(message => {
diff --git a/src/app/components/home/home-page/home-page.component.ts b/src/app/components/home/home-page/home-page.component.ts
index b630f9533564845829998678511c6a22e9c0be36..eec655fa3ea823dfbd746378b02d76df1eb5bd9f 100644
--- a/src/app/components/home/home-page/home-page.component.ts
+++ b/src/app/components/home/home-page/home-page.component.ts
@@ -7,7 +7,7 @@ import { Component, OnInit } from '@angular/core';
 })
 export class HomePageComponent implements OnInit {
 
-  mobile: boolean = true;
+  mobile = true;
 
   constructor() { }
 
diff --git a/src/app/components/participant/content-choice-participant/content-choice-participant.component.ts b/src/app/components/participant/content-choice-participant/content-choice-participant.component.ts
index 8d9a8635dd53f594a4ac4f8cbee738933dd80481..e780f3015610d418146a173b0d09ca7bc3ee2d8c 100644
--- a/src/app/components/participant/content-choice-participant/content-choice-participant.component.ts
+++ b/src/app/components/participant/content-choice-participant/content-choice-participant.component.ts
@@ -52,7 +52,7 @@ export class ContentChoiceParticipantComponent implements OnInit {
   }
 
   submitAnswer(): void {
-    let selectedAnswers: number[] = [];
+    const selectedAnswers: number[] = [];
     if (this.content.multiple) {
       for (let i = 0; i < this.checkedAnswers.length; i++) {
         if (this.checkedAnswers[i].checked) {
diff --git a/src/app/components/shared/header/header.component.ts b/src/app/components/shared/header/header.component.ts
index c5d28a7f134191acbeaa6ea96293c1ed3ca6203a..c57ae654c08b16823232c0b5d4339d4946cd6fee 100644
--- a/src/app/components/shared/header/header.component.ts
+++ b/src/app/components/shared/header/header.component.ts
@@ -78,7 +78,7 @@ export class HeaderComponent implements OnInit {
     const dialogRef = this.dialog.open(LoginComponent, {
       width: '350px'
     });
-    let role = (isDozent === true) ? UserRole.CREATOR : UserRole.PARTICIPANT;
+    const role = (isDozent === true) ? UserRole.CREATOR : UserRole.PARTICIPANT;
     dialogRef.componentInstance.role = role;
     dialogRef.componentInstance.isStandard = true;
   }
diff --git a/src/app/components/shared/room-join/room-join.component.ts b/src/app/components/shared/room-join/room-join.component.ts
index 3e81020ead0fc9ef37bd8172c575579aa2e23272..07ca5cd82a638f3387c10b3da078fe9e1308855b 100644
--- a/src/app/components/shared/room-join/room-join.component.ts
+++ b/src/app/components/shared/room-join/room-join.component.ts
@@ -46,7 +46,7 @@ export class RoomJoinComponent implements OnInit {
   }
 
   getRoom(id: string): void {
-    if (id.length - (id.split(' ').length -1) < 8) {
+    if (id.length - (id.split(' ').length - 1) < 8) {
       this.translateService.get('home-page.exactly-8').subscribe(message => {
         this.notificationService.show(message);
       });
@@ -55,7 +55,7 @@ export class RoomJoinComponent implements OnInit {
         this.notificationService.show(message);
       });
     } else {
-      this.roomService.getRoomByShortId(id.replace(/\s/g, ""))
+      this.roomService.getRoomByShortId(id.replace(/\s/g, ''))
       .subscribe(room => {
         this.room = room;
         if (!room) {
@@ -75,7 +75,6 @@ export class RoomJoinComponent implements OnInit {
         }
       });
     }
-    
   }
 
   joinRoom(id: string): void {
diff --git a/src/app/interceptors/authentication.interceptor.ts b/src/app/interceptors/authentication.interceptor.ts
index 4939c7f4eb6f67c78e0b84f268fde024c75f6c84..8fddfefae77c8530277f75f39388f393b3751ad0 100644
--- a/src/app/interceptors/authentication.interceptor.ts
+++ b/src/app/interceptors/authentication.interceptor.ts
@@ -1,7 +1,13 @@
-
-import {tap} from 'rxjs/operators';
+import { tap } from 'rxjs/operators';
 import { Injectable } from '@angular/core';
-import { HttpErrorResponse, HttpEvent, HttpHandler, HttpInterceptor, HttpRequest, HttpResponse } from '@angular/common/http';
+import {
+  HttpErrorResponse,
+  HttpEvent,
+  HttpHandler,
+  HttpInterceptor,
+  HttpRequest,
+  HttpResponse
+} from '@angular/common/http';
 
 import { AuthenticationService } from '../services/http/authentication.service';
 import { NotificationService } from '../services/util/notification.service';
diff --git a/src/app/services/http/authentication.service.ts b/src/app/services/http/authentication.service.ts
index d1ab0b5dc55704b195d5dd23fcbfabcb13f37ef6..2ac6be1b6f48bbb74a695c8675540d5d2d394a14 100644
--- a/src/app/services/http/authentication.service.ts
+++ b/src/app/services/http/authentication.service.ts
@@ -1,5 +1,4 @@
-
-import {catchError, map} from 'rxjs/operators';
+import { catchError, map } from 'rxjs/operators';
 import { Injectable } from '@angular/core';
 import { User } from '../../models/user';
 import { Observable ,  of ,  BehaviorSubject } from 'rxjs';
@@ -119,13 +118,13 @@ export class AuthenticationService {
       } else {
         return 'false';
       }
-    }),catchError((e) => {
+    }), catchError((e) => {
       // check if user needs activation
       if (e.error.errorType === 'DisabledException') {
         return of('activation');
       }
       return of('false');
-    }),);
+    }), );
   }
 
   get watchUser() {
diff --git a/src/app/services/http/room.service.ts b/src/app/services/http/room.service.ts
index 4566c05902de34f4fc2ef68f1db0f19dcd91516c..3ab13d5ae45ded893b7e6885d841135dadeb473c 100644
--- a/src/app/services/http/room.service.ts
+++ b/src/app/services/http/room.service.ts
@@ -96,7 +96,7 @@ export class RoomService extends BaseHttpService {
 
   parseDefaultContentGroup(room: Room): Room {
     if (room.contentGroups) {
-      for (let cg of room.contentGroups) {
+      for (const cg of room.contentGroups) {
         if (!cg.name || cg.name === '') {
           cg.name = 'Default';
         }