diff --git a/gnuviechadmin/gnuviechadmin/settings.py b/gnuviechadmin/gnuviechadmin/settings.py
index 0d9ee46..2d8e3e5 100644
--- a/gnuviechadmin/gnuviechadmin/settings.py
+++ b/gnuviechadmin/gnuviechadmin/settings.py
@@ -24,10 +24,11 @@ SITE_NAME = basename(DJANGO_ROOT)
 
 # ######### END PATH CONFIGURATION
 
+GVA_ENVIRONMENT = get_env_variable("GVA_ENVIRONMENT", default="prod")
 
 # ######### DEBUG CONFIGURATION
 # See: https://docs.djangoproject.com/en/dev/ref/settings/#debug
-DEBUG = False
+DEBUG = (GVA_ENVIRONMENT == "local")
 # ######### END DEBUG CONFIGURATION
 
 
@@ -351,8 +352,6 @@ GVA_LINK_PHPPGADMIN = get_env_variable(
 )
 # ######### END CUSTOM APP CONFIGURATION
 
-GVA_ENVIRONMENT = get_env_variable("GVA_ENVIRONMENT", default="prod")
-
 # ######### STATIC FILE CONFIGURATION
 # See: https://docs.djangoproject.com/en/dev/ref/settings/#static-root
 STATIC_ROOT = "/srv/gva/static/"
@@ -362,11 +361,19 @@ def show_debug_toolbar(request):
     return DEBUG and GVA_ENVIRONMENT == "local"
 
 
-if GVA_ENVIRONMENT == "local":
-    # ######### DEBUG CONFIGURATION
-    # See: https://docs.djangoproject.com/en/dev/ref/settings/#debug
-    DEBUG = True
+# ######### TOOLBAR CONFIGURATION
+# See: http://django-debug-toolbar.readthedocs.org/en/latest/installation.html#explicit-setup # noqa
+INSTALLED_APPS += ("debug_toolbar",)
 
+MIDDLEWARE += ["debug_toolbar.middleware.DebugToolbarMiddleware"]
+
+DEBUG_TOOLBAR_CONFIG = {
+    "SHOW_TOOLBAR_CALLBACK": "gnuviechadmin.settings.show_debug_toolbar"
+}
+# ######### END TOOLBAR CONFIGURATION
+
+
+if GVA_ENVIRONMENT == "local":
     # See: https://docs.djangoproject.com/en/dev/ref/settings/#template-debug
     TEMPLATES[0]["OPTIONS"]["debug"] = DEBUG
     # ######### END DEBUG CONFIGURATION
@@ -381,12 +388,6 @@ if GVA_ENVIRONMENT == "local":
     CACHES = {"default": {"BACKEND": "django.core.cache.backends.locmem.LocMemCache"}}
     # ######### END CACHE CONFIGURATION
 
-    # ######### TOOLBAR CONFIGURATION
-    # See: http://django-debug-toolbar.readthedocs.org/en/latest/installation.html#explicit-setup # noqa
-    INSTALLED_APPS += ("debug_toolbar",)
-
-    MIDDLEWARE += ["debug_toolbar.middleware.DebugToolbarMiddleware"]
-
     LOGGING["handlers"].update(
         {
             "console": {
@@ -419,13 +420,6 @@ if GVA_ENVIRONMENT == "local":
             ]
         )
     )
-
-    DEBUG_TOOLBAR_PATCH_SETTINGS = False
-    DEBUG_TOOLBAR_CONFIG = {
-        "SHOW_TOOLBAR_CALLBACK": "gnuviechadmin.settings.show_debug_toolbar"
-    }
-
-    # ######### END TOOLBAR CONFIGURATION
 elif GVA_ENVIRONMENT == "test":
     ALLOWED_HOSTS = ["localhost"]
     PASSWORD_HASHERS = ("django.contrib.auth.hashers.MD5PasswordHasher",)
diff --git a/gnuviechadmin/gnuviechadmin/urls.py b/gnuviechadmin/gnuviechadmin/urls.py
index 2b6d0b1..506c09b 100644
--- a/gnuviechadmin/gnuviechadmin/urls.py
+++ b/gnuviechadmin/gnuviechadmin/urls.py
@@ -1,11 +1,11 @@
 from __future__ import absolute_import
 
+import debug_toolbar
 from django.conf.urls import include, url
-from django.conf import settings
-
 from django.contrib import admin
 from django.contrib.flatpages import views
 from django.contrib.staticfiles.urls import staticfiles_urlpatterns
+from django.urls import path
 
 admin.autodiscover()
 
@@ -28,9 +28,7 @@ urlpatterns = [
 # Uncomment the next line to serve media files in dev.
 # urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)
 
-if settings.DEBUG:  # pragma: no cover
-    import debug_toolbar
-
-    urlpatterns = [
-        url(r'^__debug__/', include(debug_toolbar.urls)),
-    ] + staticfiles_urlpatterns() + urlpatterns
+urlpatterns += staticfiles_urlpatterns()
+urlpatterns += [
+    path('__debug__/', include(debug_toolbar.urls)),
+]
diff --git a/gnuviechadmin/managemails/models.py b/gnuviechadmin/managemails/models.py
index 5d30164..6eef059 100644
--- a/gnuviechadmin/managemails/models.py
+++ b/gnuviechadmin/managemails/models.py
@@ -7,24 +7,20 @@ from __future__ import unicode_literals
 from django.db import models
 from django.utils.encoding import python_2_unicode_compatible
 from django.utils.translation import ugettext as _
-
-from passlib.hash import sha512_crypt
 from model_utils.models import TimeStampedModel
+from passlib.hash import sha512_crypt
 
 from domains.models import MailDomain
+from fileservertasks.tasks import create_file_mailbox, delete_file_mailbox
 from osusers.models import User as OsUser
 
-from fileservertasks.tasks import (
-    create_file_mailbox,
-    delete_file_mailbox,
-)
-
 
 class ActivateAbleMixin(models.Model):
     """
     Mixin for model classes that can be active or inactive.
 
     """
+
     active = models.BooleanField(default=True)
 
     class Meta:
@@ -51,10 +47,8 @@ class MailboxManager(models.Manager):
         mailboxformat = "{0}p{1:02d}"
         mailboxname = mailboxformat.format(osuser.username, count)
 
-        for box in self.values('username').filter(osuser=osuser).order_by(
-            'username'
-        ):
-            if box['username'] == mailboxname:
+        for box in self.values("username").filter(osuser=osuser).order_by("username"):
+            if box["username"] == mailboxname:
                 count += 1
                 mailboxname = mailboxformat.format(osuser.username, count)
             else:
@@ -69,9 +63,10 @@ class MailboxManager(models.Manager):
 
         """
         return self.filter(
-            models.Q(mailaddressmailbox__isnull=True) |
-            models.Q(mailaddressmailbox__mailaddress=mailaddress),
-            active=True, osuser=osuser,
+            models.Q(mailaddressmailbox__isnull=True)
+            | models.Q(mailaddressmailbox__mailaddress=mailaddress),
+            active=True,
+            osuser=osuser,
         )
 
     def unused(self, osuser):
@@ -82,7 +77,8 @@ class MailboxManager(models.Manager):
         """
         return self.filter(
             mailaddressmailbox__isnull=True,
-            active=True, osuser=osuser,
+            active=True,
+            osuser=osuser,
         )
 
     def create_mailbox(self, osuser, password=None, commit=True):
@@ -97,7 +93,8 @@ class MailboxManager(models.Manager):
 
         """
         mailbox = self.create(
-            osuser=osuser, username=self.get_next_mailbox_name(osuser))
+            osuser=osuser, username=self.get_next_mailbox_name(osuser)
+        )
         if password is not None:
             mailbox.set_password(password)
         return mailbox
@@ -109,6 +106,7 @@ class Mailbox(ActivateAbleMixin, TimeStampedModel):
     This is the model class for a mailbox.
 
     """
+
     osuser = models.ForeignKey(OsUser, on_delete=models.CASCADE)
     username = models.CharField(max_length=128, unique=True)
     password = models.CharField(max_length=255)
@@ -116,9 +114,9 @@ class Mailbox(ActivateAbleMixin, TimeStampedModel):
     objects = MailboxManager()
 
     class Meta:
-        ordering = ['osuser', 'username']
-        verbose_name = _('Mailbox')
-        verbose_name_plural = _('Mailboxes')
+        ordering = ["osuser", "username"]
+        verbose_name = _("Mailbox")
+        verbose_name_plural = _("Mailboxes")
 
     def set_password(self, password):
         """
@@ -127,7 +125,7 @@ class Mailbox(ActivateAbleMixin, TimeStampedModel):
         :param str password: the clear text password
 
         """
-        self.password = sha512_crypt.encrypt(password)
+        self.password = sha512_crypt.hash(password)
 
     def save(self, *args, **kwargs):
         # TODO: refactor to use signals
@@ -144,11 +142,9 @@ class Mailbox(ActivateAbleMixin, TimeStampedModel):
         Get a list of mail addresses assigned to this mailbox.
 
         """
-        addrs = [
-            mbadr.mailaddress for mbadr in
-            self.mailaddressmailbox_set.all()
-        ]
+        addrs = [mbadr.mailaddress for mbadr in self.mailaddressmailbox_set.all()]
         return addrs
+
     mailaddresses = property(get_mailaddresses)
 
     def __str__(self):
@@ -161,15 +157,17 @@ class MailAddress(ActivateAbleMixin, TimeStampedModel, models.Model):
     This is the model class for a mail address.
 
     """
-    localpart = models.CharField(_('local part'), max_length=128)
+
+    localpart = models.CharField(_("local part"), max_length=128)
     domain = models.ForeignKey(
-        MailDomain, verbose_name=_('domain'), on_delete=models.CASCADE)
+        MailDomain, verbose_name=_("domain"), on_delete=models.CASCADE
+    )
 
     class Meta:
-        ordering = ['domain', 'localpart']
-        unique_together = ('localpart', 'domain')
-        verbose_name = _('Mail address')
-        verbose_name_plural = _('Mail addresses')
+        ordering = ["domain", "localpart"]
+        unique_together = ("localpart", "domain")
+        verbose_name = _("Mail address")
+        verbose_name_plural = _("Mail addresses")
 
     def __str__(self):
         return "{0}@{1}".format(self.localpart, self.domain)
@@ -220,8 +218,7 @@ class MailAddress(ActivateAbleMixin, TimeStampedModel, models.Model):
             if MailAddressMailbox.objects.filter(mailaddress=self).exists():
                 mabox = MailAddressMailbox.objects.get(mailaddress=self)
                 mabox.delete()
-            forwards = MailAddressForward.objects.filter(
-                mailaddress=self).all()
+            forwards = MailAddressForward.objects.filter(mailaddress=self).all()
             for item in forwards:
                 if item.target not in addresses:
                     item.delete()
@@ -250,14 +247,19 @@ class MailAddressMailbox(TimeStampedModel, models.Model):
     This is the model class to assign a mail address to a mailbox.
 
     """
+
     mailaddress = models.OneToOneField(
-        MailAddress, verbose_name=_('mailaddress'), primary_key=True,
-        on_delete=models.CASCADE)
+        MailAddress,
+        verbose_name=_("mailaddress"),
+        primary_key=True,
+        on_delete=models.CASCADE,
+    )
     mailbox = models.ForeignKey(
-        Mailbox, verbose_name=_('mailbox'), on_delete=models.CASCADE)
+        Mailbox, verbose_name=_("mailbox"), on_delete=models.CASCADE
+    )
 
     class Meta:
-        unique_together = ('mailaddress', 'mailbox')
+        unique_together = ("mailaddress", "mailbox")
 
     def __str__(self):
         return self.mailbox.username
@@ -268,8 +270,9 @@ class MailAddressForward(TimeStampedModel, models.Model):
     This is a model class to map mail addresses to forwarding addresses.
 
     """
+
     mailaddress = models.ForeignKey(MailAddress, on_delete=models.CASCADE)
     target = models.EmailField(max_length=254)
 
     class Meta:
-        unique_together = ('mailaddress', 'target')
+        unique_together = ("mailaddress", "target")
diff --git a/gnuviechadmin/osusers/models.py b/gnuviechadmin/osusers/models.py
index 14d36ff..7772d97 100644
--- a/gnuviechadmin/osusers/models.py
+++ b/gnuviechadmin/osusers/models.py
@@ -3,22 +3,19 @@ This module defines the database models of operating system users.
 
 """
 import base64
-from datetime import date
 import logging
 import os
+from datetime import date
 
-from django.db import models, transaction
 from django.conf import settings
 from django.core.exceptions import ValidationError
+from django.db import models, transaction
 from django.dispatch import Signal
 from django.utils import timezone
 from django.utils.translation import ugettext as _
-
 from model_utils.models import TimeStampedModel
-
 from passlib.hash import sha512_crypt
-from passlib.utils import generate_password
-
+from passlib.pwd import genword
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -150,7 +147,7 @@ class UserManager(models.Manager):
 
         If username is None the result of :py:meth:`get_next_username` is used.
         If password is None a new password will be generated using passlib's
-        :py:func:`generate_password`.
+        :py:func:`genword`.
 
         :param customer: Django User instance this user is associated to
         :param str username: the username or None
@@ -166,7 +163,7 @@ class UserManager(models.Manager):
         if username is None:
             username = self.get_next_username()
         if password is None:
-            password = generate_password()
+            password = genword(entropy=128)
         homedir = os.path.join(settings.OSUSER_HOME_BASEPATH, username)
         group = Group.objects.create(groupname=username, gid=gid)
         user = self.create(
diff --git a/gnuviechadmin/templates/base.html b/gnuviechadmin/templates/base.html
index b6c10fb..8040f63 100644
--- a/gnuviechadmin/templates/base.html
+++ b/gnuviechadmin/templates/base.html
@@ -1,4 +1,4 @@
-{% load staticfiles i18n account %}<!DOCTYPE html>
+{% load static i18n account %}<!DOCTYPE html>
 <html lang="en">
   <head>
     <meta charset="utf-8">
diff --git a/gnuviechadmin/webtasks/tasks.py b/gnuviechadmin/webtasks/tasks.py
index 4abd4af..2fd1dcc 100644
--- a/gnuviechadmin/webtasks/tasks.py
+++ b/gnuviechadmin/webtasks/tasks.py
@@ -1,5 +1,5 @@
 """
-This module defines Celery_ tasks to manage website configurations.
+This module defines Celery tasks to manage website configurations.
 
 """
 from __future__ import absolute_import