diff --git a/src/becca/entities/bbranch.ts b/src/becca/entities/bbranch.ts
index 677bc75ef..2b6dc8657 100644
--- a/src/becca/entities/bbranch.ts
+++ b/src/becca/entities/bbranch.ts
@@ -141,7 +141,7 @@ class BBranch extends AbstractBeccaEntity<BBranch> {
      *
      * @returns true if note has been deleted, false otherwise
      */
-    deleteBranch(deleteId: string, taskContext: TaskContext): boolean {
+    deleteBranch(deleteId?: string, taskContext?: TaskContext): boolean {
         if (!deleteId) {
             deleteId = utils.randomString(10);
         }
diff --git a/src/etapi/app_info.js b/src/etapi/app_info.js
deleted file mode 100644
index 20c1381f0..000000000
--- a/src/etapi/app_info.js
+++ /dev/null
@@ -1,12 +0,0 @@
-const appInfo = require('../services/app_info');
-const eu = require('./etapi_utils');
-
-function register(router) {
-    eu.route(router, 'get', '/etapi/app-info', (req, res, next) => {
-        res.status(200).json(appInfo);
-    });
-}
-
-module.exports = {
-    register
-};
diff --git a/src/etapi/app_info.ts b/src/etapi/app_info.ts
new file mode 100644
index 000000000..81830fec2
--- /dev/null
+++ b/src/etapi/app_info.ts
@@ -0,0 +1,13 @@
+import { Router } from 'express';
+import appInfo = require('../services/app_info');
+import eu = require('./etapi_utils');
+
+function register(router: Router) {
+    eu.route(router, 'get', '/etapi/app-info', (req, res, next) => {
+        res.status(200).json(appInfo);
+    });
+}
+
+export = {
+    register
+};
diff --git a/src/etapi/attachments.js b/src/etapi/attachments.ts
similarity index 77%
rename from src/etapi/attachments.js
rename to src/etapi/attachments.ts
index 8a3802061..258b9a186 100644
--- a/src/etapi/attachments.js
+++ b/src/etapi/attachments.ts
@@ -1,11 +1,13 @@
-const becca = require('../becca/becca');
-const eu = require('./etapi_utils');
-const mappers = require('./mappers.js');
-const v = require('./validators.js');
-const utils = require('../services/utils');
+import becca = require('../becca/becca');
+import eu = require('./etapi_utils');
+import mappers = require('./mappers');
+import v = require('./validators');
+import utils = require('../services/utils');
+import { Router } from 'express';
+import { AttachmentRow } from '../becca/entities/rows';
 
-function register(router) {
-    const ALLOWED_PROPERTIES_FOR_CREATE_ATTACHMENT = {
+function register(router: Router) {
+    const ALLOWED_PROPERTIES_FOR_CREATE_ATTACHMENT: ValidatorMap = {
         'ownerId': [v.notNull, v.isNoteId],
         'role': [v.notNull, v.isString],
         'mime': [v.notNull, v.isString],
@@ -14,18 +16,21 @@ function register(router) {
         'content': [v.isString],
     };
 
-    eu.route(router, 'post' ,'/etapi/attachments', (req, res, next) => {
-        const params = {};
-
-        eu.validateAndPatch(params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_ATTACHMENT);
+    eu.route(router, 'post', '/etapi/attachments', (req, res, next) => {
+        const _params: Partial<AttachmentRow> = {};
+        eu.validateAndPatch(_params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_ATTACHMENT);
+        const params = _params as AttachmentRow;
 
         try {
+            if (!params.ownerId) {
+                throw new Error("Missing owner ID.");
+            }
             const note = becca.getNoteOrThrow(params.ownerId);
             const attachment = note.saveAttachment(params);
 
             res.status(201).json(mappers.mapAttachmentToPojo(attachment));
         }
-        catch (e) {
+        catch (e: any) {
             throw new eu.EtapiError(500, eu.GENERIC_CODE, e.message);
         }
     });
@@ -43,7 +48,7 @@ function register(router) {
         'position': [v.notNull, v.isInteger],
     };
 
-    eu.route(router, 'patch' ,'/etapi/attachments/:attachmentId', (req, res, next) => {
+    eu.route(router, 'patch', '/etapi/attachments/:attachmentId', (req, res, next) => {
         const attachment = eu.getAndCheckAttachment(req.params.attachmentId);
 
         if (attachment.isProtected) {
@@ -85,7 +90,7 @@ function register(router) {
         return res.sendStatus(204);
     });
 
-    eu.route(router, 'delete' ,'/etapi/attachments/:attachmentId', (req, res, next) => {
+    eu.route(router, 'delete', '/etapi/attachments/:attachmentId', (req, res, next) => {
         const attachment = becca.getAttachment(req.params.attachmentId);
 
         if (!attachment) {
diff --git a/src/etapi/attributes.js b/src/etapi/attributes.ts
similarity index 71%
rename from src/etapi/attributes.js
rename to src/etapi/attributes.ts
index 17ca00c07..d5b407fb3 100644
--- a/src/etapi/attributes.js
+++ b/src/etapi/attributes.ts
@@ -1,17 +1,19 @@
-const becca = require('../becca/becca');
-const eu = require('./etapi_utils');
-const mappers = require('./mappers.js');
-const attributeService = require('../services/attributes');
-const v = require('./validators.js');
+import becca = require('../becca/becca');
+import eu = require('./etapi_utils');
+import mappers = require('./mappers');
+import attributeService = require('../services/attributes');
+import v = require('./validators');
+import { Router } from 'express';
+import { AttributeRow } from '../becca/entities/rows';
 
-function register(router) {
+function register(router: Router) {
     eu.route(router, 'get', '/etapi/attributes/:attributeId', (req, res, next) => {
         const attribute = eu.getAndCheckAttribute(req.params.attributeId);
 
         res.json(mappers.mapAttributeToPojo(attribute));
     });
 
-    const ALLOWED_PROPERTIES_FOR_CREATE_ATTRIBUTE = {
+    const ALLOWED_PROPERTIES_FOR_CREATE_ATTRIBUTE: ValidatorMap = {
         'attributeId': [v.mandatory, v.notNull, v.isValidEntityId],
         'noteId': [v.mandatory, v.notNull, v.isNoteId],
         'type': [v.mandatory, v.notNull, v.isAttributeType],
@@ -21,21 +23,21 @@ function register(router) {
         'position': [v.notNull, v.isInteger]
     };
 
-    eu.route(router, 'post' ,'/etapi/attributes', (req, res, next) => {
+    eu.route(router, 'post', '/etapi/attributes', (req, res, next) => {
         if (req.body.type === 'relation') {
             eu.getAndCheckNote(req.body.value);
         }
 
-        const params = {};
-
-        eu.validateAndPatch(params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_ATTRIBUTE);
+        const _params = {};
+        eu.validateAndPatch(_params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_ATTRIBUTE);
+        const params: AttributeRow = _params as AttributeRow;
 
         try {
             const attr = attributeService.createAttribute(params);
 
             res.status(201).json(mappers.mapAttributeToPojo(attr));
         }
-        catch (e) {
+        catch (e: any) {
             throw new eu.EtapiError(500, eu.GENERIC_CODE, e.message);
         }
     });
@@ -49,7 +51,7 @@ function register(router) {
         'position': [v.notNull, v.isInteger]
     };
 
-    eu.route(router, 'patch' ,'/etapi/attributes/:attributeId', (req, res, next) => {
+    eu.route(router, 'patch', '/etapi/attributes/:attributeId', (req, res, next) => {
         const attribute = eu.getAndCheckAttribute(req.params.attributeId);
 
         if (attribute.type === 'label') {
@@ -65,7 +67,7 @@ function register(router) {
         res.json(mappers.mapAttributeToPojo(attribute));
     });
 
-    eu.route(router, 'delete' ,'/etapi/attributes/:attributeId', (req, res, next) => {
+    eu.route(router, 'delete', '/etapi/attributes/:attributeId', (req, res, next) => {
         const attribute = becca.getAttribute(req.params.attributeId);
 
         if (!attribute) {
@@ -78,6 +80,6 @@ function register(router) {
     });
 }
 
-module.exports = {
+export = {
     register
 };
diff --git a/src/etapi/auth.js b/src/etapi/auth.ts
similarity index 75%
rename from src/etapi/auth.js
rename to src/etapi/auth.ts
index 7a3b258d8..e6c440e52 100644
--- a/src/etapi/auth.js
+++ b/src/etapi/auth.ts
@@ -1,9 +1,10 @@
-const becca = require('../becca/becca');
-const eu = require('./etapi_utils');
-const passwordEncryptionService = require('../services/encryption/password_encryption');
-const etapiTokenService = require('../services/etapi_tokens');
+import becca = require('../becca/becca');
+import eu = require('./etapi_utils');
+import passwordEncryptionService = require('../services/encryption/password_encryption');
+import etapiTokenService = require('../services/etapi_tokens');
+import { RequestHandler, Router } from 'express';
 
-function register(router, loginMiddleware) {
+function register(router: Router, loginMiddleware: RequestHandler[]) {
     eu.NOT_AUTHENTICATED_ROUTE(router, 'post', '/etapi/auth/login', loginMiddleware, (req, res, next) => {
         const {password, tokenName} = req.body;
 
@@ -38,6 +39,6 @@ function register(router, loginMiddleware) {
     });
 }
 
-module.exports = {
+export = {
     register
 }
diff --git a/src/etapi/backup.js b/src/etapi/backup.ts
similarity index 54%
rename from src/etapi/backup.js
rename to src/etapi/backup.ts
index 7900570c4..50c2bd49c 100644
--- a/src/etapi/backup.js
+++ b/src/etapi/backup.ts
@@ -1,7 +1,9 @@
-const eu = require('./etapi_utils');
-const backupService = require('../services/backup');
+import { Router } from "express";
 
-function register(router) {
+import eu = require('./etapi_utils');
+import backupService = require('../services/backup');
+
+function register(router: Router) {
     eu.route(router, 'put', '/etapi/backup/:backupName', async (req, res, next) => {
         await backupService.backupNow(req.params.backupName);
 
@@ -9,6 +11,6 @@ function register(router) {
     });
 }
 
-module.exports = {
+export = {
     register
 };
diff --git a/src/etapi/branches.js b/src/etapi/branches.ts
similarity index 64%
rename from src/etapi/branches.js
rename to src/etapi/branches.ts
index e0337e5cb..d41a5857b 100644
--- a/src/etapi/branches.js
+++ b/src/etapi/branches.ts
@@ -1,11 +1,14 @@
-const becca = require('../becca/becca');
-const eu = require('./etapi_utils');
-const mappers = require('./mappers.js');
-const BBranch = require('../becca/entities/bbranch');
-const entityChangesService = require('../services/entity_changes');
-const v = require('./validators.js');
+import { Router } from "express";
 
-function register(router) {
+import becca = require('../becca/becca');
+import eu = require('./etapi_utils');
+import mappers = require('./mappers');
+import BBranch = require('../becca/entities/bbranch');
+import entityChangesService = require('../services/entity_changes');
+import v = require('./validators');
+import { BranchRow } from "../becca/entities/rows";
+
+function register(router: Router) {
     eu.route(router, 'get', '/etapi/branches/:branchId', (req, res, next) => {
         const branch = eu.getAndCheckBranch(req.params.branchId);
 
@@ -20,17 +23,17 @@ function register(router) {
         'isExpanded': [v.notNull, v.isBoolean]
     };
 
-    eu.route(router, 'post' ,'/etapi/branches', (req, res, next) => {
-        const params = {};
-
-        eu.validateAndPatch(params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_BRANCH);
+    eu.route(router, 'post', '/etapi/branches', (req, res, next) => {
+        const _params = {};
+        eu.validateAndPatch(_params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_BRANCH);
+        const params: BranchRow = _params as BranchRow;
 
         const existing = becca.getBranchFromChildAndParent(params.noteId, params.parentNoteId);
 
         if (existing) {
-            existing.notePosition = params.notePosition;
-            existing.prefix = params.prefix;
-            existing.isExpanded = params.isExpanded;
+            existing.notePosition = params.notePosition as number;
+            existing.prefix = params.prefix as string;
+            existing.isExpanded = params.isExpanded as boolean;
             existing.save();
 
             return res.status(200).json(mappers.mapBranchToPojo(existing));
@@ -39,7 +42,7 @@ function register(router) {
                 const branch = new BBranch(params).save();
 
                 res.status(201).json(mappers.mapBranchToPojo(branch));
-            } catch (e) {
+            } catch (e: any) {
                 throw new eu.EtapiError(400, eu.GENERIC_CODE, e.message);
             }
         }
@@ -51,7 +54,7 @@ function register(router) {
         'isExpanded': [v.notNull, v.isBoolean]
     };
 
-    eu.route(router, 'patch' ,'/etapi/branches/:branchId', (req, res, next) => {
+    eu.route(router, 'patch', '/etapi/branches/:branchId', (req, res, next) => {
         const branch = eu.getAndCheckBranch(req.params.branchId);
 
         eu.validateAndPatch(branch, req.body, ALLOWED_PROPERTIES_FOR_PATCH);
@@ -60,7 +63,7 @@ function register(router) {
         res.json(mappers.mapBranchToPojo(branch));
     });
 
-    eu.route(router, 'delete' ,'/etapi/branches/:branchId', (req, res, next) => {
+    eu.route(router, 'delete', '/etapi/branches/:branchId', (req, res, next) => {
         const branch = becca.getBranch(req.params.branchId);
 
         if (!branch) {
@@ -72,7 +75,7 @@ function register(router) {
         res.sendStatus(204);
     });
 
-    eu.route(router, 'post' ,'/etapi/refresh-note-ordering/:parentNoteId', (req, res, next) => {
+    eu.route(router, 'post', '/etapi/refresh-note-ordering/:parentNoteId', (req, res, next) => {
         eu.getAndCheckNote(req.params.parentNoteId);
 
         entityChangesService.putNoteReorderingEntityChange(req.params.parentNoteId, "etapi");
@@ -81,6 +84,6 @@ function register(router) {
     });
 }
 
-module.exports = {
+export = {
     register
 };
diff --git a/src/etapi/etapi-interface.ts b/src/etapi/etapi-interface.ts
new file mode 100644
index 000000000..c0b6d3f04
--- /dev/null
+++ b/src/etapi/etapi-interface.ts
@@ -0,0 +1,3 @@
+type ValidatorFunc = (obj: unknown) => (string | undefined);
+
+type ValidatorMap = Record<string, ValidatorFunc[]>;
\ No newline at end of file
diff --git a/src/etapi/etapi_utils.js b/src/etapi/etapi_utils.ts
similarity index 62%
rename from src/etapi/etapi_utils.js
rename to src/etapi/etapi_utils.ts
index b5928f4d7..bcb589325 100644
--- a/src/etapi/etapi_utils.js
+++ b/src/etapi/etapi_utils.ts
@@ -1,15 +1,22 @@
-const cls = require('../services/cls');
-const sql = require('../services/sql');
-const log = require('../services/log');
-const becca = require('../becca/becca');
-const etapiTokenService = require('../services/etapi_tokens');
-const config = require('../services/config');
+import cls = require('../services/cls');
+import sql = require('../services/sql');
+import log = require('../services/log');
+import becca = require('../becca/becca');
+import etapiTokenService = require('../services/etapi_tokens');
+import config = require('../services/config');
+import { NextFunction, Request, RequestHandler, Response, Router } from 'express';
+import { AppRequest, AppRequestHandler } from '../routes/route-interface';
 const GENERIC_CODE = "GENERIC";
 
+type HttpMethod = "all" | "get" | "post" | "put" | "delete" | "patch" | "options" | "head";
+
 const noAuthentication = config.General && config.General.noAuthentication === true;
 
 class EtapiError extends Error {
-    constructor(statusCode, code, message) {
+    statusCode: number;
+    code: string;
+
+    constructor(statusCode: number, code: string, message: string) {
         super();
 
         this.statusCode = statusCode;
@@ -18,7 +25,7 @@ class EtapiError extends Error {
     }
 }
 
-function sendError(res, statusCode, code, message) {
+function sendError(res: Response, statusCode: number, code: string, message: string) {
     return res
         .set('Content-Type', 'application/json')
         .status(statusCode)
@@ -29,7 +36,7 @@ function sendError(res, statusCode, code, message) {
         }));
 }
 
-function checkEtapiAuth(req, res, next) {
+function checkEtapiAuth(req: Request, res: Response, next: NextFunction) {
     if (noAuthentication || etapiTokenService.isValidAuthHeader(req.headers.authorization)) {
         next();
     }
@@ -38,7 +45,7 @@ function checkEtapiAuth(req, res, next) {
     }
 }
 
-function processRequest(req, res, routeHandler, next, method, path) {
+function processRequest(req: Request, res: Response, routeHandler: AppRequestHandler, next: NextFunction, method: string, path: string) {
     try {
         cls.namespace.bindEmitter(req);
         cls.namespace.bindEmitter(res);
@@ -47,11 +54,11 @@ function processRequest(req, res, routeHandler, next, method, path) {
             cls.set('componentId', "etapi");
             cls.set('localNowDateTime', req.headers['trilium-local-now-datetime']);
 
-            const cb = () => routeHandler(req, res, next);
+            const cb = () => routeHandler(req as AppRequest, res, next);
 
             return sql.transactional(cb);
         });
-    } catch (e) {
+    } catch (e: any) {
         log.error(`${method} ${path} threw exception ${e.message} with stacktrace: ${e.stack}`);
 
         if (e instanceof EtapiError) {
@@ -62,15 +69,15 @@ function processRequest(req, res, routeHandler, next, method, path) {
     }
 }
 
-function route(router, method, path, routeHandler) {
-    router[method](path, checkEtapiAuth, (req, res, next) => processRequest(req, res, routeHandler, next, method, path));
+function route(router: Router, method: HttpMethod, path: string, routeHandler: AppRequestHandler) {
+    router[method](path, checkEtapiAuth, (req: Request, res: Response, next: NextFunction) => processRequest(req, res, routeHandler, next, method, path));
 }
 
-function NOT_AUTHENTICATED_ROUTE(router, method, path, middleware, routeHandler) {
-    router[method](path, ...middleware, (req, res, next) => processRequest(req, res, routeHandler, next, method, path));
+function NOT_AUTHENTICATED_ROUTE(router: Router, method: HttpMethod, path: string, middleware: RequestHandler[], routeHandler: RequestHandler) {
+    router[method](path, ...middleware, (req: Request, res: Response, next: NextFunction) => processRequest(req, res, routeHandler, next, method, path));
 }
 
-function getAndCheckNote(noteId) {
+function getAndCheckNote(noteId: string) {
     const note = becca.getNote(noteId);
 
     if (note) {
@@ -81,7 +88,7 @@ function getAndCheckNote(noteId) {
     }
 }
 
-function getAndCheckAttachment(attachmentId) {
+function getAndCheckAttachment(attachmentId: string) {
     const attachment = becca.getAttachment(attachmentId, {includeContentLength: true});
 
     if (attachment) {
@@ -92,7 +99,7 @@ function getAndCheckAttachment(attachmentId) {
     }
 }
 
-function getAndCheckBranch(branchId) {
+function getAndCheckBranch(branchId: string) {
     const branch = becca.getBranch(branchId);
 
     if (branch) {
@@ -103,7 +110,7 @@ function getAndCheckBranch(branchId) {
     }
 }
 
-function getAndCheckAttribute(attributeId) {
+function getAndCheckAttribute(attributeId: string) {
     const attribute = becca.getAttribute(attributeId);
 
     if (attribute) {
@@ -114,7 +121,7 @@ function getAndCheckAttribute(attributeId) {
     }
 }
 
-function validateAndPatch(target, source, allowedProperties) {
+function validateAndPatch(target: any, source: any, allowedProperties: ValidatorMap) {
     for (const key of Object.keys(source)) {
         if (!(key in allowedProperties)) {
             throw new EtapiError(400, "PROPERTY_NOT_ALLOWED", `Property '${key}' is not allowed for this method.`);
@@ -136,7 +143,7 @@ function validateAndPatch(target, source, allowedProperties) {
     }
 }
 
-module.exports = {
+export = {
     EtapiError,
     sendError,
     route,
diff --git a/src/etapi/mappers.js b/src/etapi/mappers.ts
similarity index 81%
rename from src/etapi/mappers.js
rename to src/etapi/mappers.ts
index d94cf2e69..537b51738 100644
--- a/src/etapi/mappers.js
+++ b/src/etapi/mappers.ts
@@ -1,5 +1,9 @@
-/** @param {BNote} note */
-function mapNoteToPojo(note) {
+import BAttachment = require("../becca/entities/battachment");
+import BAttribute = require("../becca/entities/battribute");
+import BBranch = require("../becca/entities/bbranch");
+import BNote = require("../becca/entities/bnote");
+
+function mapNoteToPojo(note: BNote) {
     return {
         noteId: note.noteId,
         isProtected: note.isProtected,
@@ -19,8 +23,7 @@ function mapNoteToPojo(note) {
     };
 }
 
-/** @param {BBranch} branch */
-function mapBranchToPojo(branch) {
+function mapBranchToPojo(branch: BBranch) {
     return {
         branchId: branch.branchId,
         noteId: branch.noteId,
@@ -32,8 +35,7 @@ function mapBranchToPojo(branch) {
     };
 }
 
-/** @param {BAttribute} attr */
-function mapAttributeToPojo(attr) {
+function mapAttributeToPojo(attr: BAttribute) {
     return {
         attributeId: attr.attributeId,
         noteId: attr.noteId,
@@ -46,8 +48,7 @@ function mapAttributeToPojo(attr) {
     };
 }
 
-/** @param {BAttachment} attachment */
-function mapAttachmentToPojo(attachment) {
+function mapAttachmentToPojo(attachment: BAttachment) {
     return {
         attachmentId: attachment.attachmentId,
         ownerId: attachment.ownerId,
@@ -63,7 +64,7 @@ function mapAttachmentToPojo(attachment) {
     };
 }
 
-module.exports = {
+export = {
     mapNoteToPojo,
     mapBranchToPojo,
     mapAttributeToPojo,
diff --git a/src/etapi/notes.js b/src/etapi/notes.ts
similarity index 70%
rename from src/etapi/notes.js
rename to src/etapi/notes.ts
index 3ca024367..620e9f3d8 100644
--- a/src/etapi/notes.js
+++ b/src/etapi/notes.ts
@@ -1,20 +1,26 @@
-const becca = require('../becca/becca');
-const utils = require('../services/utils');
-const eu = require('./etapi_utils');
-const mappers = require('./mappers.js');
-const noteService = require('../services/notes');
-const TaskContext = require('../services/task_context');
-const v = require('./validators.js');
-const searchService = require('../services/search/services/search');
-const SearchContext = require('../services/search/search_context');
-const zipExportService = require('../services/export/zip');
-const zipImportService = require('../services/import/zip');
+import becca = require('../becca/becca');
+import utils = require('../services/utils');
+import eu = require('./etapi_utils');
+import mappers = require('./mappers');
+import noteService = require('../services/notes');
+import TaskContext = require('../services/task_context');
+import v = require('./validators');
+import searchService = require('../services/search/services/search');
+import SearchContext = require('../services/search/search_context');
+import zipExportService = require('../services/export/zip');
+import zipImportService = require('../services/import/zip');
+import { Router } from 'express';
+import { AppRequest } from '../routes/route-interface';
+import { ParsedQs } from 'qs';
+import { NoteParams } from '../services/note-interface';
+import BNote = require('../becca/entities/bnote');
+import { SearchParams } from '../services/search/services/types';
 
-function register(router) {
+function register(router: Router) {
     eu.route(router, 'get', '/etapi/notes', (req, res, next) => {
-        const {search} = req.query;
+        const { search } = req.query;
 
-        if (!search?.trim()) {
+        if (typeof search !== "string" || !search?.trim()) {
             throw new eu.EtapiError(400, 'SEARCH_QUERY_PARAM_MANDATORY', "'search' query parameter is mandatory.");
         }
 
@@ -24,8 +30,8 @@ function register(router) {
         const searchResults = searchService.findResultsWithQuery(search, searchContext);
         const foundNotes = searchResults.map(sr => becca.notes[sr.noteId]);
 
-        const resp = {
-            results: foundNotes.map(note => mappers.mapNoteToPojo(note))
+        const resp: any = {
+            results: foundNotes.map(note => mappers.mapNoteToPojo(note)),
         };
 
         if (searchContext.debugInfo) {
@@ -41,7 +47,7 @@ function register(router) {
         res.json(mappers.mapNoteToPojo(note));
     });
 
-    const ALLOWED_PROPERTIES_FOR_CREATE_NOTE = {
+    const ALLOWED_PROPERTIES_FOR_CREATE_NOTE: ValidatorMap = {
         'parentNoteId': [v.mandatory, v.notNull, v.isNoteId],
         'title': [v.mandatory, v.notNull, v.isString],
         'type': [v.mandatory, v.notNull, v.isNoteType],
@@ -55,10 +61,10 @@ function register(router) {
         'utcDateCreated': [v.notNull, v.isString, v.isUtcDateTime]
     };
 
-    eu.route(router, 'post' ,'/etapi/create-note', (req, res, next) => {
-        const params = {};
-
-        eu.validateAndPatch(params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_NOTE);
+    eu.route(router, 'post', '/etapi/create-note', (req, res, next) => {
+        const _params = {};
+        eu.validateAndPatch(_params, req.body, ALLOWED_PROPERTIES_FOR_CREATE_NOTE);
+        const params = _params as NoteParams;
 
         try {
             const resp = noteService.createNewNote(params);
@@ -68,7 +74,7 @@ function register(router) {
                 branch: mappers.mapBranchToPojo(resp.branch)
             });
         }
-        catch (e) {
+        catch (e: any) {
             return eu.sendError(res, 500, eu.GENERIC_CODE, e.message);
         }
     });
@@ -81,7 +87,7 @@ function register(router) {
         'utcDateCreated': [v.notNull, v.isString, v.isUtcDateTime]
     };
 
-    eu.route(router, 'patch' ,'/etapi/notes/:noteId', (req, res, next) => {
+    eu.route(router, 'patch', '/etapi/notes/:noteId', (req, res, next) => {
         const note = eu.getAndCheckNote(req.params.noteId);
 
         if (note.isProtected) {
@@ -94,8 +100,8 @@ function register(router) {
         res.json(mappers.mapNoteToPojo(note));
     });
 
-    eu.route(router, 'delete' ,'/etapi/notes/:noteId', (req, res, next) => {
-        const {noteId} = req.params;
+    eu.route(router, 'delete', '/etapi/notes/:noteId', (req, res, next) => {
+        const { noteId } = req.params;
 
         const note = becca.getNote(noteId);
 
@@ -139,11 +145,11 @@ function register(router) {
         return res.sendStatus(204);
     });
 
-    eu.route(router, 'get' ,'/etapi/notes/:noteId/export', (req, res, next) => {
+    eu.route(router, 'get', '/etapi/notes/:noteId/export', (req, res, next) => {
         const note = eu.getAndCheckNote(req.params.noteId);
         const format = req.query.format || "html";
 
-        if (!["html", "markdown"].includes(format)) {
+        if (typeof format !== "string" || !["html", "markdown"].includes(format)) {
             throw new eu.EtapiError(400, "UNRECOGNIZED_EXPORT_FORMAT", `Unrecognized export format '${format}', supported values are 'html' (default) or 'markdown'.`);
         }
 
@@ -153,10 +159,10 @@ function register(router) {
         // (e.g. branchIds are not seen in UI), that we export "note export" instead.
         const branch = note.getParentBranches()[0];
 
-        zipExportService.exportToZip(taskContext, branch, format, res);
+        zipExportService.exportToZip(taskContext, branch, format as "html" | "markdown", res);
     });
 
-    eu.route(router, 'post' ,'/etapi/notes/:noteId/import', (req, res, next) => {
+    eu.route(router, 'post', '/etapi/notes/:noteId/import', (req, res, next) => {
         const note = eu.getAndCheckNote(req.params.noteId);
         const taskContext = new TaskContext('no-progress-reporting');
 
@@ -168,7 +174,7 @@ function register(router) {
         }); // we need better error handling here, async errors won't be properly processed.
     });
 
-    eu.route(router, 'post' ,'/etapi/notes/:noteId/revision', (req, res, next) => {
+    eu.route(router, 'post', '/etapi/notes/:noteId/revision', (req, res, next) => {
         const note = eu.getAndCheckNote(req.params.noteId);
 
         note.saveRevision();
@@ -178,7 +184,7 @@ function register(router) {
 
     eu.route(router, 'get', '/etapi/notes/:noteId/attachments', (req, res, next) => {
         const note = eu.getAndCheckNote(req.params.noteId);
-        const attachments = note.getAttachments({includeContentLength: true})
+        const attachments = note.getAttachments({ includeContentLength: true })
 
         res.json(
             attachments.map(attachment => mappers.mapAttachmentToPojo(attachment))
@@ -186,23 +192,24 @@ function register(router) {
     });
 }
 
-function parseSearchParams(req) {
-    const rawSearchParams = {
+function parseSearchParams(req: AppRequest) {
+    const rawSearchParams: SearchParams = {
         fastSearch: parseBoolean(req.query, 'fastSearch'),
         includeArchivedNotes: parseBoolean(req.query, 'includeArchivedNotes'),
-        ancestorNoteId: req.query['ancestorNoteId'],
-        ancestorDepth: req.query['ancestorDepth'], // e.g. "eq5"
-        orderBy: req.query['orderBy'],
-        orderDirection: parseOrderDirection(req.query, 'orderDirection'),
+        ancestorNoteId: parseString(req.query['ancestorNoteId']),
+        ancestorDepth: parseString(req.query['ancestorDepth']), // e.g. "eq5"
+        orderBy: parseString(req.query['orderBy']),
+        // TODO: Check why the order direction was provided as a number, but it's a string everywhere else.
+        orderDirection: parseOrderDirection(req.query, 'orderDirection') as unknown as string,
         limit: parseInteger(req.query, 'limit'),
         debug: parseBoolean(req.query, 'debug')
     };
 
-    const searchParams = {};
+    const searchParams: SearchParams = {};
 
-    for (const paramName of Object.keys(rawSearchParams)) {
+    for (const paramName of Object.keys(rawSearchParams) as (keyof SearchParams)[]) {
         if (rawSearchParams[paramName] !== undefined) {
-            searchParams[paramName] = rawSearchParams[paramName];
+            (searchParams as any)[paramName] = rawSearchParams[paramName];
         }
     }
 
@@ -211,7 +218,15 @@ function parseSearchParams(req) {
 
 const SEARCH_PARAM_ERROR = "SEARCH_PARAM_VALIDATION_ERROR";
 
-function parseBoolean(obj, name) {
+function parseString(value: string | ParsedQs | string[] | ParsedQs[] | undefined): string | undefined {
+    if (typeof value === "string") {
+        return value;
+    }
+
+    return undefined;
+}
+
+function parseBoolean(obj: any, name: string) {
     if (!(name in obj)) {
         return undefined;
     }
@@ -223,7 +238,7 @@ function parseBoolean(obj, name) {
     return obj[name] === 'true';
 }
 
-function parseOrderDirection(obj, name) {
+function parseOrderDirection(obj: any, name: string) {
     if (!(name in obj)) {
         return undefined;
     }
@@ -237,7 +252,7 @@ function parseOrderDirection(obj, name) {
     return integer;
 }
 
-function parseInteger(obj, name) {
+function parseInteger(obj: any, name: string) {
     if (!(name in obj)) {
         return undefined;
     }
@@ -251,6 +266,6 @@ function parseInteger(obj, name) {
     return integer;
 }
 
-module.exports = {
+export = {
     register
 };
diff --git a/src/etapi/spec.js b/src/etapi/spec.ts
similarity index 67%
rename from src/etapi/spec.js
rename to src/etapi/spec.ts
index 83ac93a4b..530249d46 100644
--- a/src/etapi/spec.js
+++ b/src/etapi/spec.ts
@@ -1,10 +1,12 @@
-const fs = require('fs');
-const path = require('path');
+import { Router } from "express";
+
+import fs = require('fs');
+import path = require('path');
 
 const specPath = path.join(__dirname, 'etapi.openapi.yaml');
-let spec = null;
+let spec: string | null = null;
 
-function register(router) {
+function register(router: Router) {
     router.get('/etapi/etapi.openapi.yaml', (req, res, next) => {
         if (!spec) {
             spec = fs.readFileSync(specPath, 'utf8');
@@ -15,6 +17,6 @@ function register(router) {
     });
 }
 
-module.exports = {
+export = {
     register
 };
diff --git a/src/etapi/special_notes.js b/src/etapi/special_notes.ts
similarity index 72%
rename from src/etapi/special_notes.js
rename to src/etapi/special_notes.ts
index 68ef75fae..4de5d77df 100644
--- a/src/etapi/special_notes.js
+++ b/src/etapi/special_notes.ts
@@ -1,13 +1,14 @@
-const specialNotesService = require('../services/special_notes');
-const dateNotesService = require('../services/date_notes');
-const eu = require('./etapi_utils');
-const mappers = require('./mappers.js');
+import specialNotesService = require('../services/special_notes');
+import dateNotesService = require('../services/date_notes');
+import eu = require('./etapi_utils');
+import mappers = require('./mappers');
+import { Router } from 'express';
 
-const getDateInvalidError = date => new eu.EtapiError(400, "DATE_INVALID", `Date "${date}" is not valid.`);
-const getMonthInvalidError = month => new eu.EtapiError(400, "MONTH_INVALID", `Month "${month}" is not valid.`);
-const getYearInvalidError = year => new eu.EtapiError(400, "YEAR_INVALID", `Year "${year}" is not valid.`);
+const getDateInvalidError = (date: string) => new eu.EtapiError(400, "DATE_INVALID", `Date "${date}" is not valid.`);
+const getMonthInvalidError = (month: string)=> new eu.EtapiError(400, "MONTH_INVALID", `Month "${month}" is not valid.`);
+const getYearInvalidError = (year: string) => new eu.EtapiError(400, "YEAR_INVALID", `Year "${year}" is not valid.`);
 
-function isValidDate(date) {
+function isValidDate(date: string) {
     if (!/[0-9]{4}-[0-9]{2}-[0-9]{2}/.test(date)) {
         return false;
     }
@@ -15,7 +16,7 @@ function isValidDate(date) {
     return !!Date.parse(date);
 }
 
-function register(router) {
+function register(router: Router) {
     eu.route(router, 'get', '/etapi/inbox/:date', (req, res, next) => {
         const { date } = req.params;
 
@@ -72,6 +73,6 @@ function register(router) {
     });
 }
 
-module.exports = {
+export = {
     register
 };
diff --git a/src/etapi/validators.js b/src/etapi/validators.ts
similarity index 71%
rename from src/etapi/validators.js
rename to src/etapi/validators.ts
index bcca288ca..ce6935c7c 100644
--- a/src/etapi/validators.js
+++ b/src/etapi/validators.ts
@@ -1,19 +1,19 @@
-const noteTypeService = require('../services/note_types');
-const dateUtils = require('../services/date_utils');
+import noteTypeService = require('../services/note_types');
+import dateUtils = require('../services/date_utils');
 
-function mandatory(obj) {
-    if (obj === undefined ) {
+function mandatory(obj: unknown) {
+    if (obj === undefined) {
         return `mandatory, but not set`;
     }
 }
 
-function notNull(obj) {
+function notNull(obj: unknown) {
     if (obj === null) {
         return `cannot be null`;
     }
 }
 
-function isString(obj) {
+function isString(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
@@ -23,23 +23,23 @@ function isString(obj) {
     }
 }
 
-function isLocalDateTime(obj) {
-    if (obj === undefined || obj === null) {
+function isLocalDateTime(obj: unknown) {
+    if (typeof obj !== "string") {
         return;
     }
 
     return dateUtils.validateLocalDateTime(obj);
 }
 
-function isUtcDateTime(obj) {
-    if (obj === undefined || obj === null) {
+function isUtcDateTime(obj: unknown) {
+    if (typeof obj !== "string") {
         return;
     }
 
     return dateUtils.validateUtcDateTime(obj);
 }
 
-function isBoolean(obj) {
+function isBoolean(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
@@ -49,7 +49,7 @@ function isBoolean(obj) {
     }
 }
 
-function isInteger(obj) {
+function isInteger(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
@@ -59,7 +59,7 @@ function isInteger(obj) {
     }
 }
 
-function isNoteId(obj) {
+function isNoteId(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
@@ -75,29 +75,29 @@ function isNoteId(obj) {
     }
 }
 
-function isNoteType(obj) {
+function isNoteType(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
 
     const noteTypes = noteTypeService.getNoteTypeNames();
 
-    if (!noteTypes.includes(obj)) {
+    if (typeof obj !== "string" || !noteTypes.includes(obj)) {
         return `'${obj}' is not a valid note type, allowed types are: ${noteTypes.join(", ")}`;
     }
 }
 
-function isAttributeType(obj) {
+function isAttributeType(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
 
-    if (!['label', 'relation'].includes(obj)) {
+    if (typeof obj !== "string" || !['label', 'relation'].includes(obj)) {
         return `'${obj}' is not a valid attribute type, allowed types are: label, relation`;
     }
 }
 
-function isValidEntityId(obj) {
+function isValidEntityId(obj: unknown) {
     if (obj === undefined || obj === null) {
         return;
     }
@@ -107,7 +107,7 @@ function isValidEntityId(obj) {
     }
 }
 
-module.exports = {
+export = {
     mandatory,
     notNull,
     isString,
diff --git a/src/routes/api/files.ts b/src/routes/api/files.ts
index 44cd1dacf..682bc94e4 100644
--- a/src/routes/api/files.ts
+++ b/src/routes/api/files.ts
@@ -20,6 +20,13 @@ function updateFile(req: AppRequest) {
     const note = becca.getNoteOrThrow(req.params.noteId);
 
     const file = req.file;
+    if (!file) {
+        return {
+            uploaded: false,
+            message: `Missing file.`
+        };
+    }
+
     note.saveRevision();
 
     note.mime = file.mimetype.toLowerCase();
@@ -39,6 +46,12 @@ function updateFile(req: AppRequest) {
 function updateAttachment(req: AppRequest) {
     const attachment = becca.getAttachmentOrThrow(req.params.attachmentId);
     const file = req.file;
+    if (!file) {
+        return {
+            uploaded: false,
+            message: `Missing file.`
+        };
+    }
 
     attachment.getNote().saveRevision();
 
diff --git a/src/routes/api/image.ts b/src/routes/api/image.ts
index a0ee6140c..b00c7fd7f 100644
--- a/src/routes/api/image.ts
+++ b/src/routes/api/image.ts
@@ -88,6 +88,13 @@ function updateImage(req: AppRequest) {
 
     const note = becca.getNoteOrThrow(noteId);
 
+    if (!file) {
+        return {
+            uploaded: false,
+            message: `Missing image data.`
+        };
+    }
+
     if (!["image/png", "image/jpeg", "image/gif", "image/webp", "image/svg+xml"].includes(file.mimetype)) {
         return {
             uploaded: false,
diff --git a/src/routes/api/sender.ts b/src/routes/api/sender.ts
index 515011739..8d20c1fd9 100644
--- a/src/routes/api/sender.ts
+++ b/src/routes/api/sender.ts
@@ -11,6 +11,13 @@ import { AppRequest } from '../route-interface';
 function uploadImage(req: AppRequest) {
     const file = req.file;
 
+    if (!file) {
+        return {
+            uploaded: false,
+            message: `Missing image data.`
+        };
+    }
+
     if (!["image/png", "image/jpeg", "image/gif", "image/webp", "image/svg+xml"].includes(file.mimetype)) {
         return [400, `Unknown image type: ${file.mimetype}`];
     }
diff --git a/src/routes/login.ts b/src/routes/login.ts
index a4c13ca90..cce214fbe 100644
--- a/src/routes/login.ts
+++ b/src/routes/login.ts
@@ -67,7 +67,7 @@ function login(req: AppRequest, res: Response) {
             if (rememberMe) {
                 req.session.cookie.maxAge = 21 * 24 * 3600000;  // 3 weeks
             } else {
-                req.session.cookie.expires = false;
+                req.session.cookie.expires = null;
             }
 
             req.session.loggedIn = true;
diff --git a/src/routes/route-interface.ts b/src/routes/route-interface.ts
index acf86cbe5..4510c5de6 100644
--- a/src/routes/route-interface.ts
+++ b/src/routes/route-interface.ts
@@ -1,5 +1,5 @@
-import { Request } from "express";
-import { File } from "../services/import/common";
+import { NextFunction, Request, Response } from "express";
+import { Session, SessionData } from "express-session";
 
 export interface AppRequest extends Request {
     headers: {
@@ -7,14 +7,15 @@ export interface AppRequest extends Request {
         "trilium-cred"?: string;
         "x-local-date"?: string;
         "x-labels"?: string;
+        "trilium-local-now-datetime"?: string;
     }
-    session: {
-        loggedIn: boolean;   
-        cookie: {
-            maxAge: number;
-            expires: boolean
-        };
-        regenerate: (callback: () => void) => void;     
+    session: Session & Partial<SessionData> & {
+        loggedIn: boolean;
     }
-    file: File;
-}
\ No newline at end of file
+}
+
+export type AppRequestHandler = (
+    req: AppRequest,
+    res: Response,
+    next: NextFunction
+) => void;
\ No newline at end of file
diff --git a/src/routes/routes.js b/src/routes/routes.js
index 182639b84..00c803cb0 100644
--- a/src/routes/routes.js
+++ b/src/routes/routes.js
@@ -61,14 +61,14 @@ const relationMapApiRoute = require('./api/relation-map');
 const otherRoute = require('./api/other');
 const shareRoutes = require('../share/routes.js');
 
-const etapiAuthRoutes = require('../etapi/auth.js');
+const etapiAuthRoutes = require('../etapi/auth');
 const etapiAppInfoRoutes = require('../etapi/app_info');
-const etapiAttachmentRoutes = require('../etapi/attachments.js');
+const etapiAttachmentRoutes = require('../etapi/attachments');
 const etapiAttributeRoutes = require('../etapi/attributes');
-const etapiBranchRoutes = require('../etapi/branches.js');
-const etapiNoteRoutes = require('../etapi/notes.js');
+const etapiBranchRoutes = require('../etapi/branches');
+const etapiNoteRoutes = require('../etapi/notes');
 const etapiSpecialNoteRoutes = require('../etapi/special_notes');
-const etapiSpecRoute = require('../etapi/spec.js');
+const etapiSpecRoute = require('../etapi/spec');
 const etapiBackupRoute = require('../etapi/backup');
 
 const csrfMiddleware = csurf({