diff --git a/app/app/settings.py b/app/app/settings.py
index 1163ddbb..84577b02 100644
--- a/app/app/settings.py
+++ b/app/app/settings.py
@@ -10,9 +10,10 @@ https://docs.djangoproject.com/en/2.0/ref/settings/
 Any setting that is configured via an environment variable may
 also be set in a `.env` file in the project base directory.
 """
+import importlib.util
+import sys
 from os import path
 
-import django_heroku
 import dj_database_url
 from environs import Env
 from furl import furl
@@ -53,13 +54,13 @@ INSTALLED_APPS = [
     'django.contrib.staticfiles',
     'server.apps.ServerConfig',
     'api.apps.ApiConfig',
-    'widget_tweaks',
+    # 'widget_tweaks',
     'rest_framework',
     'rest_framework.authtoken',
     'django_filters',
     'social_django',
     'polymorphic',
-    'webpack_loader',
+    # 'webpack_loader',
     'corsheaders',
     'drf_yasg'
 ]
@@ -83,7 +84,7 @@ MIDDLEWARE = [
     'django.contrib.messages.middleware.MessageMiddleware',
     'django.middleware.clickjacking.XFrameOptionsMiddleware',
     'social_django.middleware.SocialAuthExceptionMiddleware',
-    'applicationinsights.django.ApplicationInsightsMiddleware',
+    # 'applicationinsights.django.ApplicationInsightsMiddleware',
     'corsheaders.middleware.CorsMiddleware',
 ]
 
@@ -277,7 +278,13 @@ LOGIN_URL = '/login/'
 LOGIN_REDIRECT_URL = '/projects/'
 LOGOUT_REDIRECT_URL = '/'
 
-django_heroku.settings(locals(), test_runner=False)
+# dynamic import to avoid installing psycopg2 on pip installation.
+name = 'django_heroku'
+if (spec := importlib.util.find_spec(name)) is not None:
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[name] = module
+    spec.loader.exec_module(module)
+    django_heroku.settings(locals(), test_runner=False)
 
 # Change 'default' database configuration with $DATABASE_URL.
 DATABASES['default'].update(dj_database_url.config(
@@ -309,7 +316,7 @@ CSRF_COOKIE_SECURE = env.bool('CSRF_COOKIE_SECURE', False)
 CSRF_TRUSTED_ORIGINS = env.list('CSRF_TRUSTED_ORIGINS', [])
 
 # Allow all host headers
-# ALLOWED_HOSTS = ['*']
+ALLOWED_HOSTS = ['*']
 
 # Size of the batch for creating documents
 # on the import phase
diff --git a/app/doccano/doccano.py b/app/doccano/doccano.py
index 4186cf9c..c6f0a610 100644
--- a/app/doccano/doccano.py
+++ b/app/doccano/doccano.py
@@ -4,13 +4,13 @@ import subprocess
 
 
 def main():
-    parser = argparse.ArgumentParser(description='doccano.')
+    parser = argparse.ArgumentParser(description='doccano, text annotation for machine learning practitioners.')
     parser.add_argument('--username', type=str, default='admin', help='admin username')
     parser.add_argument('--password', type=str, default='password', help='admin password')
     parser.add_argument('--email', type=str, default='example@example.com', help='admin email')
-    parser.add_argument('--port', type=int, default=8000, help='port')
-    parser.add_argument('--workers', type=int, default=1, help='workers')
-    parser.add_argument('--database_url', type=str, default='sqlite:///doccano.db', help='data store')
+    parser.add_argument('--port', type=int, default=8000, help='port number')
+    # parser.add_argument('--workers', type=int, default=1, help='the number of workers')
+    parser.add_argument('--database_url', type=str, default='sqlite:///doccano.db', help='the database URL')
     args = parser.parse_args()
 
     os.environ.setdefault('DEBUG', 'False')
diff --git a/setup.py b/setup.py
index 57538e8b..2a584c7a 100644
--- a/setup.py
+++ b/setup.py
@@ -6,7 +6,7 @@ import os
 from setuptools import find_packages, setup
 
 NAME = 'doccano'
-DESCRIPTION = 'doccano'
+DESCRIPTION = 'doccano, text annotation tool for machine learning practitioners'
 URL = 'https://github.com/doccano/doccano'
 EMAIL = 'hiroki.nakayama.py@gmail.com'
 AUTHOR = 'Hironsan'
@@ -16,8 +16,9 @@ here = os.path.abspath(os.path.dirname(__file__))
 with io.open(os.path.join(here, 'README.md'), encoding='utf-8') as f:
     long_description = '\n' + f.read()
 
-# required = ['requests', 'boto3', 'pydantic', 'jinja2']
-required = [line.rstrip() for line in io.open(os.path.join(here, 'app/requirements.txt')) if not line.startswith('psy')]
+# Todo: make a cleaned requirements.txt
+required = [line.rstrip() for line in io.open(os.path.join(here, 'app/requirements.txt'))
+            if not line.startswith(('psycopg2', 'django-heroku', 'django-mssql-backend'))]
 
 setup(
     name=NAME,
@@ -36,6 +37,10 @@ setup(
         ]
     },
     install_requires=required,
+    extras_require={
+        'postgresql': ['psycopg2-binary>=2.8.6'],
+        'mssql': ['django-mssql-backend>=2.8.1'],
+    },
     include_package_data=True,
     license=LICENSE,
     classifiers=[