diff --git a/serve.py b/serve.py
index fc22d9e..1e81363 100755
--- a/serve.py
+++ b/serve.py
@@ -7,17 +7,15 @@ import base64
 import uuid
 import logging.config
 import argparse
-from concurrent.futures import ThreadPoolExecutor
 import mimetypes
 import signal
+import asyncio
 
 # user installed libraries
 import tornado.ioloop
 import tornado.web
 import tornado.httpserver
-from tornado import template, iostream, gen
-from tornado.concurrent import run_on_executor
-from tornado.platform.asyncio import to_tornado_future
+from tornado import template, iostream
 
 # this project
 from learnapp import LearnApp
@@ -79,11 +77,14 @@ class LoginHandler(BaseHandler):
         self.render('login.html', error='')
 
     # @gen.coroutine
-    def post(self):
+    async def post(self):
         uid = self.get_body_argument('uid')
         pw = self.get_body_argument('pw')
 
-        if self.learn.login(uid, pw):
+        loop = asyncio.get_event_loop()
+        login_ok = await loop.run_in_executor(None, self.learn.login, uid, pw)
+
+        if login_ok:
             self.set_secure_cookie("user", str(uid), expires_days=30)
             self.redirect(self.get_argument("next", "/"))
         else:
@@ -179,14 +180,13 @@ class FileHandler(BaseHandler):
                 chunk = f.read(self.chunk_size)
                 while chunk:
                     try:
-                        self.write(chunk)   # write the cunk to response
+                        self.write(chunk)   # write the chunk to response
                         await self.flush()  # flush the current chunk to socket
                     except iostream.StreamClosedError:
                         break  # client closed the connection
                     finally:
                         del chunk
-                        await gen.sleep(0.000000001) # 1 nanosecond (hack)
-                        # FIXME in the upcomming tornado 5.0 use `await asyncio.sleep(0)` instead
+                        await asyncio.sleep(0)   # 1 nanosecond (hack)
                     chunk = f.read(self.chunk_size)
 
 
@@ -194,8 +194,6 @@ class FileHandler(BaseHandler):
 # respond to AJAX to get a JSON question
 # ----------------------------------------------------------------------------
 class QuestionHandler(BaseHandler):
-    executor = ThreadPoolExecutor()  # max_workers=5*n_cpus?
-
     templates = {
         'checkbox':         'question-checkbox.html',
         'radio':            'question-radio.html',
@@ -212,12 +210,6 @@ class QuestionHandler(BaseHandler):
         # 'alert':      '', FIXME
     }
 
-    # Blocking function to be run on the executor
-    @run_on_executor()
-    def check_answer(self, user, answer):
-        return self.learn.check_answer(user, answer)
-
-
     # --- get question to render
     @tornado.web.authenticated
     def get(self):
@@ -255,7 +247,10 @@ class QuestionHandler(BaseHandler):
                 answer = answer[0]
 
         # check answer in another thread (nonblocking)
-        grade = await to_tornado_future(self.check_answer(user, answer))
+        loop = asyncio.get_event_loop()
+        grade = await loop.run_in_executor(None, self.learn.check_answer, user, answer)
+
+        print('grade = ', grade)
         question = self.learn.get_student_question(user)
 
         if grade <= 0.999:      # wrong answer
@@ -277,7 +272,8 @@ class QuestionHandler(BaseHandler):
                 })
         else:                  # right answer, get next question in the topic
             template = self.templates[question['type']]
-            question_html = self.render_string(template, question=question, md=md_to_html)
+            question_html = self.render_string(
+                template, question=question, md=md_to_html)
             self.write({
                 'method': 'new_question',
                 'params': {
--
libgit2 0.21.2