diff --git a/controllers/Default.js b/controllers/Default.js
index 48dc3fa..4ccb114 100644
--- a/controllers/Default.js
+++ b/controllers/Default.js
@@ -1,9 +1,7 @@
-'use strict';
+import utils from '../utils/writer.js';
+import Service from '../service/DefaultService.js';
 
-const utils = require('../utils/writer.js');
-const Service = require('../service/DefaultService.js');
-
-exports.resolve = function resolve (req, res) {
+export const resolve = function resolve (req, res) {
     const identifier = req.params['identifier'];
     const accept = req.get('accept');
     console.log('request: ' + identifier);
diff --git a/index.cjs b/index.js
similarity index 76%
rename from index.cjs
rename to index.js
index 56718ee..f6b3596 100644
--- a/index.cjs
+++ b/index.js
@@ -1,8 +1,6 @@
-'use strict';
-
-const http = require('http');
-const express = require('express');
-const Controller = require('./controllers/Default.js');
+import http from 'http';
+import express from 'express';
+import Controller from './controllers/Default.js';
 
 const serverPort = 8080;
 
diff --git a/package.json b/package.json
index 16689d6..d453d4d 100644
--- a/package.json
+++ b/package.json
@@ -2,17 +2,17 @@
   "name": "uni-resolver-driver-did-key",
   "version": "0.5.0",
   "description": "Universal Resolver Driver",
-  "main": "index.cjs",
+  "main": "index.js",
   "scripts": {
     "prestart": "npm install",
-    "start": "node index.cjs"
+    "start": "node index.js"
   },
   "keywords": [
     "swagger"
   ],
   "license": "Unlicense",
   "private": true,
-  "type": "commonjs",
+  "type": "module",
   "dependencies": {
     "@malachit/did-key-jwk-jcs-pub": "0.3.0-unstable.12",
     "@transmute/did-key-bls12381": "0.3.0-unstable.10",
diff --git a/service/DefaultService.js b/service/DefaultService.js
index 5cd6aeb..1f1d5a4 100644
--- a/service/DefaultService.js
+++ b/service/DefaultService.js
@@ -1,6 +1,4 @@
-'use strict';
-
-const didKey = require('@malachit/did-key.js');
+import didKey from '@malachit/did-key.js';
 
 /**
  * Resolve a DID or other identifier.
@@ -9,7 +7,7 @@ const didKey = require('@malachit/did-key.js');
  * accept String The requested MIME type of the DID document or DID resolution result. (optional)
  * returns Object
  **/
-exports.resolve = function(identifier,accept) {
+export const resolve = function(identifier,accept) {
   return new Promise(function(resolve, reject) {
     didKey.resolve(identifier)
     .then(function(didResolutionResult) {
diff --git a/utils/writer.js b/utils/writer.js
index 3cee5c6..ea4c0cd 100644
--- a/utils/writer.js
+++ b/utils/writer.js
@@ -3,11 +3,11 @@ var ResponsePayload = function(code, payload) {
   this.payload = payload;
 }
 
-exports.respondWithCode = function(code, payload) {
+export const respondWithCode = function(code, payload) {
   return new ResponsePayload(code, payload);
 }
 
-var writeJson = exports.writeJson = function(response, arg1, arg2) {
+export const writeJson = function(response, arg1, arg2) {
   var code;
   var payload;