diff --git a/src/abstractions/messaging.service.ts b/src/abstractions/messaging.service.ts
index 6bafce93e40..a38b4c7f7b2 100644
--- a/src/abstractions/messaging.service.ts
+++ b/src/abstractions/messaging.service.ts
@@ -1,3 +1,3 @@
-export interface MessagingService {
-    send(subscriber: string, arg?: any): void;
+export abstract class MessagingService {
+    send: (subscriber: string, arg?: any) => void;
 }
diff --git a/src/abstractions/settings.service.ts b/src/abstractions/settings.service.ts
index 97d2bca9750..6104c1d1be2 100644
--- a/src/abstractions/settings.service.ts
+++ b/src/abstractions/settings.service.ts
@@ -1,6 +1,6 @@
-export interface SettingsService {
-    clearCache(): void;
-    getEquivalentDomains(): Promise<any>;
-    setEquivalentDomains(equivalentDomains: string[][]): Promise<any>;
-    clear(userId: string): Promise<void>;
+export abstract class SettingsService {
+    clearCache: () => void;
+    getEquivalentDomains: () => Promise<any>;
+    setEquivalentDomains: (equivalentDomains: string[][]) => Promise<any>;
+    clear: (userId: string) => Promise<void>;
 }
diff --git a/src/abstractions/user.service.ts b/src/abstractions/user.service.ts
index 7afbd0b7486..5621c3be502 100644
--- a/src/abstractions/user.service.ts
+++ b/src/abstractions/user.service.ts
@@ -1,12 +1,13 @@
-export interface UserService {
+export abstract class UserService {
     userId: string;
     email: string;
     stamp: string;
-    setUserIdAndEmail(userId: string, email: string): Promise<any>;
-    setSecurityStamp(stamp: string): Promise<any>;
-    getUserId(): Promise<string>;
-    getEmail(): Promise<string>;
-    getSecurityStamp(): Promise<string>;
-    clear(): Promise<any>;
-    isAuthenticated(): Promise<boolean>;
+
+    setUserIdAndEmail: (userId: string, email: string) => Promise<any>;
+    setSecurityStamp: (stamp: string) => Promise<any>;
+    getUserId: () => Promise<string>;
+    getEmail: () => Promise<string>;
+    getSecurityStamp: () => Promise<string>;
+    clear: () => Promise<any>;
+    isAuthenticated: () => Promise<boolean>;
 }
diff --git a/src/services/settings.service.ts b/src/services/settings.service.ts
index 87302a638c5..506bdf01a08 100644
--- a/src/services/settings.service.ts
+++ b/src/services/settings.service.ts
@@ -1,4 +1,4 @@
-import { SettingsService as SettingsServiceInterface } from '../abstractions/settings.service';
+import { SettingsService as SettingsServiceAbstraction } from '../abstractions/settings.service';
 import { StorageService } from '../abstractions/storage.service';
 import { UserService } from '../abstractions/user.service';
 
@@ -7,7 +7,7 @@ const Keys = {
     equivalentDomains: 'equivalentDomains',
 };
 
-export class SettingsService implements SettingsServiceInterface {
+export class SettingsService implements SettingsServiceAbstraction {
     private settingsCache: any;
 
     constructor(private userService: UserService, private storageService: StorageService) {
diff --git a/src/services/user.service.ts b/src/services/user.service.ts
index aa2b19e179f..1949cadb483 100644
--- a/src/services/user.service.ts
+++ b/src/services/user.service.ts
@@ -1,6 +1,6 @@
 import { StorageService } from '../abstractions/storage.service';
 import { TokenService } from '../abstractions/token.service';
-import { UserService as UserServiceInterface } from '../abstractions/user.service';
+import { UserService as UserServiceAbsrtaction } from '../abstractions/user.service';
 
 const Keys = {
     userId: 'userId',
@@ -8,7 +8,7 @@ const Keys = {
     stamp: 'securityStamp',
 };
 
-export class UserService implements UserServiceInterface {
+export class UserService implements UserServiceAbsrtaction {
     userId: string;
     email: string;
     stamp: string;