diff --git a/.travis.yml b/.travis.yml
index 24ea9cd1b..7f018c94a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,6 +19,7 @@ before_install:
   - conda info -a
   - conda create -q -n test-environment -c conda-forge python=$PYTHON_VERSION jupyter_server pytest==3.10.1 pytest-cov nodejs flake8
   - source activate test-environment
+  - pip install --upgrade --no-deps --force-reinstall git+https://github.com/maartenbreddels/jupyter_server.git@fix_tornado6
 install:
   - pip install ".[test]"
 before_script:
diff --git a/setup.py b/setup.py
index 00876d4d3..d753331dc 100644
--- a/setup.py
+++ b/setup.py
@@ -158,7 +158,7 @@ def run(self):
     },
     'install_requires': [
         'jupyter_server>=0.0.3',
-        'nbconvert>=5.4,<6'
+        'nbconvert>=5.4.1,<6'
     ],
     'extras_require': {
         'test': ['mock', 'pytest<4', 'pytest-tornado5']