diff --git a/src/App.ts b/src/App.ts
index 77a791d..65168fc 100644
--- a/src/App.ts
+++ b/src/App.ts
@@ -104,7 +104,7 @@ export default class App extends Application {
         this.use(redisComponent);
         this.use(new SessionComponent(redisComponent));
         this.use(new AuthComponent(new class extends AuthGuard<MagicLink | AuthToken> {
-            public async getProofForSession(session: Session): Promise<any | null> {
+            public async getProofForSession(session: Session): Promise<MagicLink | AuthToken | null> {
                 return await MagicLink.bySessionId(
                     session.id,
                     [MagicLinkActionType.LOGIN, MagicLinkActionType.REGISTER],
@@ -122,7 +122,7 @@ export default class App extends Application {
                     return token;
                 }
 
-                return super.getProofForRequest(req);
+                return await super.getProofForRequest(req);
             }
         }(this)));
 
diff --git a/src/SlugGenerator.ts b/src/SlugGenerator.ts
index e0e92b1..dda5c6b 100644
--- a/src/SlugGenerator.ts
+++ b/src/SlugGenerator.ts
@@ -14,4 +14,4 @@ export default async function generateSlug(tries: number): Promise<string> {
         i++;
     } while (i < tries);
     throw new ServerError('Failed to generate slug; newly generated slug size should be increased by 1.');
-};
+}
diff --git a/src/Utils.ts b/src/Utils.ts
index 366f680..ef61cb4 100644
--- a/src/Utils.ts
+++ b/src/Utils.ts
@@ -1,4 +1,4 @@
-export function encodeRFC5987ValueChars(str: string) {
+export function encodeRFC5987ValueChars(str: string): string {
     return encodeURIComponent(str).
         // Note that although RFC3986 reserves "!", RFC5987 does not,
         // so we do not need to escape it
diff --git a/src/controllers/AboutController.ts b/src/controllers/AboutController.ts
index 281c3be..4b92b19 100644
--- a/src/controllers/AboutController.ts
+++ b/src/controllers/AboutController.ts
@@ -2,7 +2,7 @@ import Controller from "swaf/Controller";
 import {Request, Response} from "express";
 
 export default class AboutController extends Controller {
-    routes(): void {
+    public routes(): void {
         this.get('/', this.getAbout, 'home');
         this.get('/', this.getAbout, 'about');
     }
diff --git a/src/controllers/AuthTokenController.ts b/src/controllers/AuthTokenController.ts
index 974f543..5cfdbc9 100644
--- a/src/controllers/AuthTokenController.ts
+++ b/src/controllers/AuthTokenController.ts
@@ -5,7 +5,7 @@ import AuthToken from "../models/AuthToken";
 import {BadRequestError, ForbiddenHttpError, NotFoundHttpError} from "swaf/HttpError";
 
 export default class AuthTokenController extends Controller {
-    routes(): void {
+    public routes(): void {
         this.post('/gen-auth-token', this.postGenAuthToken, 'generate-token', RequireAuthMiddleware);
         this.post('/revoke-auth-token/:id', this.postRevokeAuthToken, 'revoke-token', RequireAuthMiddleware);
     }
diff --git a/src/controllers/FileController.ts b/src/controllers/FileController.ts
index 332b371..f997260 100644
--- a/src/controllers/FileController.ts
+++ b/src/controllers/FileController.ts
@@ -13,7 +13,7 @@ import FileUploadMiddleware from "swaf/FileUploadMiddleware";
 
 
 export default class FileController extends Controller {
-    routes(): void {
+    public routes(): void {
         this.get('/files/upload', this.getFileUploader, 'file-upload', RequireAuthMiddleware);
         this.get('/files/upload/script', this.downloadLinuxScript, 'file-linux-script');
         this.post('/files/post', this.postFileFrontend, 'post-file-frontend', RequireAuthMiddleware, FileUploadFormMiddleware);
@@ -45,12 +45,18 @@ export default class FileController extends Controller {
 
     protected async postFileFrontend(req: Request, res: Response): Promise<void> {
         req.body.type = 'file';
-        await FileController.handleFileUpload(req.body.autogen_url === undefined && req.body.slug ? req.body.slug : await generateSlug(10), req, res);
+        await FileController.handleFileUpload(
+            req.body.autogen_url === undefined && req.body.slug ?
+                req.body.slug :
+                await generateSlug(10),
+            req,
+            res,
+        );
     }
 
     public static async handleFileUpload(slug: string, req: Request, res: Response): Promise<void> {
         // Check for file upload
-        if (!req.files || !req.files['upload']) {
+        if (Object.keys(req.files).indexOf('upload') < 0) {
             throw new BadRequestError('No file received.', 'You must upload exactly one (1) file.', req.url);
         }
 
@@ -75,7 +81,7 @@ export default class FileController extends Controller {
         });
 
         await file.save();
-        fs.renameSync(upload.path, file.storage_path!);
+        fs.renameSync(upload.path, file.getOrFail('storage_path'));
 
         const domain = req.body.url_domain || config.get<string[]>('allowed_url_domains')[config.get<number>('default_url_domain_for_files')];
         res.format({
@@ -122,7 +128,7 @@ export default class FileController extends Controller {
     }
 
     public static async deleteFile(file: FileModel): Promise<void> {
-        fs.unlinkSync(file.storage_path!);
+        fs.unlinkSync(file.getOrFail('storage_path'));
         await file.delete();
         log.info('Deleted', file.storage_path, `(${file.real_name})`);
     }
diff --git a/src/controllers/LinkController.ts b/src/controllers/LinkController.ts
index 60680e7..6535e28 100644
--- a/src/controllers/LinkController.ts
+++ b/src/controllers/LinkController.ts
@@ -14,7 +14,7 @@ import {promisify} from "util";
 import {log} from "swaf/Logger";
 
 export default class LinkController extends Controller {
-    routes(): void {
+    public routes(): void {
         this.post('/', this.postFile, 'post-file', RequireRequestAuthMiddleware, FileUploadFormMiddleware);
         this.delete('/:slug', FileController.deleteFileRoute, 'delete-file', RequireRequestAuthMiddleware);
         this.get('/:slug', this.getFile, 'get-file');
@@ -29,7 +29,6 @@ export default class LinkController extends Controller {
     }
 
     protected async getFile(req: Request, res: Response, next: NextFunction): Promise<void> {
-        console.log('get file', req.params.slug)
         const file = await FileModel.getBySlug(req.params.slug);
         if (!file) return next();
         if (file.shouldBeDeleted()) {
@@ -37,16 +36,16 @@ export default class LinkController extends Controller {
             return next();
         }
 
-        const fileName = file.real_name!;
+        const fileName = file.getOrFail('real_name');
 
         switch (file.storage_type) {
-            case 'local':
-                const stats = await promisify(fs.stat)(file.storage_path!);
+            case 'local': {
+                const stats = await promisify(fs.stat)(file.getOrFail('storage_path'));
 
                 // If file is bigger than max hotlink size, fallback to express download
                 if (stats.size > config.get<number>('max_hotlink_size') * 1024 * 1024) {
                     log.info(`Fallback to express download for file of size ${stats.size}`);
-                    return res.download(file.storage_path!, fileName);
+                    return res.download(file.getOrFail('storage_path'), fileName);
                 }
 
                 // File type
@@ -56,11 +55,12 @@ export default class LinkController extends Controller {
                 // File name
                 res.header('Content-Disposition', `inline; filename*=UTF-8''${encodeRFC5987ValueChars(fileName)}`);
 
-                fs.readFile(file.storage_path!, (err, data) => {
+                fs.readFile(file.getOrFail('storage_path'), (err, data) => {
                     if (err) return next(err);
                     res.send(data);
                 });
                 break;
+            }
             default:
                 throw new ServerError(`This file cannot be served. Download protocol for ${file.storage_type} storage type not implemented.`);
         }
@@ -84,7 +84,7 @@ export default class LinkController extends Controller {
         const url = await URLRedirect.getBySlug(req.params.slug);
         if (!url) return next();
 
-        res.redirect(url.target_url!, 301);
+        res.redirect(url.getOrFail('target_url'), 301);
     }
 
     protected async deleteURL(req: Request, res: Response, next: NextFunction): Promise<void> {
@@ -94,7 +94,7 @@ export default class LinkController extends Controller {
         throw new BadRequestError(
             'Deleting url redirects is disabled for security reasons.',
             'If you still want to disable the redirection, please contact us via email.',
-            req.url
+            req.url,
         );
     }
 
diff --git a/src/controllers/MagicLinkController.ts b/src/controllers/MagicLinkController.ts
index 16fe536..942fb90 100644
--- a/src/controllers/MagicLinkController.ts
+++ b/src/controllers/MagicLinkController.ts
@@ -9,16 +9,16 @@ import App from "../App";
 import AuthComponent from "swaf/auth/AuthComponent";
 
 export default class MagicLinkController extends _MagicLinkController<App> {
-    constructor(magicLinkWebSocketListener: MagicLinkWebSocketListener<App>) {
+    public constructor(magicLinkWebSocketListener: MagicLinkWebSocketListener<App>) {
         super(magicLinkWebSocketListener);
     }
 
     protected async performAction(magicLink: MagicLink, req: Request, res: Response): Promise<void> {
         switch (magicLink.action_type) {
             case MagicLinkActionType.LOGIN:
-            case MagicLinkActionType.REGISTER:
+            case MagicLinkActionType.REGISTER: {
                 await AuthController.checkAndAuth(req, res, magicLink);
-                const proof = await this.getApp().as(AuthComponent).getAuthGuard().isAuthenticated(req.session!);
+                const proof = await this.getApp().as(AuthComponent).getAuthGuard().isAuthenticated(req.getSession());
                 const user = await proof?.getResource();
 
                 if (!res.headersSent && user) {
@@ -27,6 +27,7 @@ export default class MagicLinkController extends _MagicLinkController<App> {
                     res.redirect(req.query.redirect_uri?.toString() || Controller.route('home'));
                 }
                 break;
+            }
         }
     }
 }
diff --git a/src/controllers/URLRedirectController.ts b/src/controllers/URLRedirectController.ts
index cf42e2c..7e1a73c 100644
--- a/src/controllers/URLRedirectController.ts
+++ b/src/controllers/URLRedirectController.ts
@@ -7,7 +7,7 @@ import config from "config";
 import AuthToken from "../models/AuthToken";
 
 export default class URLRedirectController extends Controller {
-    routes(): void {
+    public routes(): void {
         this.get('/url/shrink', this.getURLShrinker, 'url-shrinker', RequireAuthMiddleware);
         this.get('/url/shrink/script', this.downloadLinuxScript, 'url-linux-script');
         this.post('/url/shrink', this.addURLFrontend, 'shrink-url', RequireAuthMiddleware);
@@ -37,7 +37,14 @@ export default class URLRedirectController extends Controller {
 
     protected async addURLFrontend(req: Request, res: Response, next: NextFunction): Promise<void> {
         req.body.type = 'url';
-        await URLRedirectController.addURL(req, res, next, req.body.autogen_url === undefined && req.body.slug ? req.body.slug : await generateSlug(10));
+        await URLRedirectController.addURL(
+            req,
+            res,
+            next,
+            req.body.autogen_url === undefined && req.body.slug ?
+                req.body.slug :
+                await generateSlug(10),
+        );
     }
 
     public static async addURL(req: Request, res: Response, next: NextFunction, slug?: string): Promise<void> {
diff --git a/src/migrations/IncreaseFilesSizeField.ts b/src/migrations/IncreaseFilesSizeField.ts
index 52cef57..4f906da 100644
--- a/src/migrations/IncreaseFilesSizeField.ts
+++ b/src/migrations/IncreaseFilesSizeField.ts
@@ -9,7 +9,4 @@ export default class IncreaseFilesSizeField extends Migration {
     public async rollback(connection: Connection): Promise<void> {
         await this.query(`ALTER TABLE files MODIFY size INT UNSIGNED`, connection);
     }
-
-    public registerModels(): void {
-    }
 }
diff --git a/src/models/AuthToken.ts b/src/models/AuthToken.ts
index c6a234f..f102941 100644
--- a/src/models/AuthToken.ts
+++ b/src/models/AuthToken.ts
@@ -6,34 +6,35 @@ import {cryptoRandomDictionary} from "swaf/Utils";
 export default class AuthToken extends Model implements AuthProof<User> {
     public id?: number = undefined;
     protected readonly user_id?: number = undefined;
-    protected readonly secret?: string = undefined;
+    private secret?: string = undefined;
     protected created_at?: Date = undefined;
     protected used_at?: Date = undefined;
     protected readonly ttl?: number = undefined;
 
-    protected init() {
+    protected init(): void {
         this.setValidation('user_id').defined().exists(User, 'id');
         this.setValidation('secret').defined().between(32, 64);
         this.setValidation('ttl').defined().min(1).max(5 * 365 * 24 * 3600 /* 5 years */);
     }
 
     protected async autoFill(): Promise<void> {
-        // @ts-ignore
-        if (!this.secret) this['secret'] = cryptoRandomDictionary(64, 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_');
+        if (!this.secret) {
+            this.secret = cryptoRandomDictionary(64, 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_');
+        }
     }
 
-    public use() {
+    public use(): void {
         this.used_at = new Date();
     }
 
-    public canDelete(user_id: number) {
+    public canDelete(user_id: number): boolean {
         return this.user_id === user_id;
     }
 
     public getExpirationDate(): Date {
         if (!this.created_at) return new Date();
 
-        return new Date(this.created_at.getTime() + this.ttl! * 1000);
+        return new Date(this.created_at.getTime() + this.getOrFail('ttl') * 1000);
     }
 
     public async getResource(): Promise<User | null> {
@@ -51,4 +52,8 @@ export default class AuthToken extends Model implements AuthProof<User> {
     public async revoke(): Promise<void> {
         await this.delete();
     }
+
+    protected getSecret(): string | undefined {
+        return this.secret;
+    }
 }
diff --git a/src/models/FileModel.ts b/src/models/FileModel.ts
index 5ac6ac0..e7a19ea 100644
--- a/src/models/FileModel.ts
+++ b/src/models/FileModel.ts
@@ -28,7 +28,7 @@ export default class FileModel extends Model {
     public created_at?: Date = undefined;
     public readonly ttl?: number = undefined;
 
-    protected init() {
+    protected init(): void {
         this.setValidation('user_id').defined().exists(User, 'id');
         this.setValidation('slug').defined().minLength(1).maxLength(259).unique(FileModel, 'slug').unique(URLRedirect, 'slug');
         this.setValidation('real_name').defined().minLength(1).maxLength(259);
@@ -40,7 +40,7 @@ export default class FileModel extends Model {
 
     public getURL(domain: string = config.get<string>('base_url')): string {
         return (/^https?:\/\//.test(domain) ? '' : 'https://') + domain + Controller.route('get-file', {
-            slug: this.slug!,
+            slug: this.getOrFail('slug'),
         });
     }
 
@@ -48,7 +48,7 @@ export default class FileModel extends Model {
         if (!this.created_at) return new Date();
         if (this.ttl === 0) return null;
 
-        return new Date(this.created_at.getTime() + this.ttl! * 1000);
+        return new Date(this.created_at.getTime() + this.getOrFail('ttl') * 1000);
     }
 
     public shouldBeDeleted(): boolean {
diff --git a/src/models/URLRedirect.ts b/src/models/URLRedirect.ts
index 77281aa..a9a1626 100644
--- a/src/models/URLRedirect.ts
+++ b/src/models/URLRedirect.ts
@@ -32,7 +32,7 @@ export default class URLRedirect extends Model {
 
     public getURL(domain: string = config.get<string>('base_url')): string {
         return (/^https?:\/\//.test(domain) ? '' : 'https://') + domain + Controller.route('get-url', {
-            slug: this.slug!,
+            slug: this.getOrFail('slug'),
         });
     }
 }