diff --git a/src/etapi/validators.js b/src/etapi/validators.js
index 59ddc1675..bcca288ca 100644
--- a/src/etapi/validators.js
+++ b/src/etapi/validators.js
@@ -1,4 +1,4 @@
-const noteTypeService = require('../services/note_types.js');
+const noteTypeService = require('../services/note_types');
 const dateUtils = require('../services/date_utils');
 
 function mandatory(obj) {
diff --git a/src/services/consistency_checks.js b/src/services/consistency_checks.js
index 3fd40a040..2e2d6385b 100644
--- a/src/services/consistency_checks.js
+++ b/src/services/consistency_checks.js
@@ -14,7 +14,7 @@ const becca = require('../becca/becca');
 const utils = require('../services/utils');
 const eraseService = require('../services/erase');
 const {sanitizeAttributeName} = require('./sanitize_attribute_name');
-const noteTypes = require('../services/note_types.js').getNoteTypeNames();
+const noteTypes = require('../services/note_types').getNoteTypeNames();
 
 class ConsistencyChecks {
     /**
diff --git a/src/services/note_types.js b/src/services/note_types.ts
similarity index 93%
rename from src/services/note_types.js
rename to src/services/note_types.ts
index f29bf8ab4..54d9d1f44 100644
--- a/src/services/note_types.js
+++ b/src/services/note_types.ts
@@ -16,7 +16,7 @@ const noteTypes = [
     { type: 'contentWidget', defaultMime: '' }
 ];
 
-function getDefaultMimeForNoteType(typeName) {
+function getDefaultMimeForNoteType(typeName: string) {
     const typeRec = noteTypes.find(nt => nt.type === typeName);
 
     if (!typeRec) {
@@ -26,7 +26,7 @@ function getDefaultMimeForNoteType(typeName) {
     return typeRec.defaultMime;
 }
 
-module.exports = {
+export = {
     getNoteTypeNames: () => noteTypes.map(nt => nt.type),
     getDefaultMimeForNoteType
 };
diff --git a/src/services/notes.js b/src/services/notes.js
index 373af1e12..fe6e84322 100644
--- a/src/services/notes.js
+++ b/src/services/notes.js
@@ -19,7 +19,7 @@ const BAttachment = require('../becca/entities/battachment');
 const dayjs = require("dayjs");
 const htmlSanitizer = require('./html_sanitizer.js');
 const ValidationError = require('../errors/validation_error');
-const noteTypesService = require('./note_types.js');
+const noteTypesService = require('./note_types');
 const fs = require("fs");
 const ws = require('./ws');
 const html2plaintext = require('html2plaintext')