diff --git a/jdav_web/jdav_web/settings.py b/jdav_web/jdav_web/settings.py
index 4e05622..96ba20d 100644
--- a/jdav_web/jdav_web/settings.py
+++ b/jdav_web/jdav_web/settings.py
@@ -36,6 +36,9 @@ MEDIA_ROOT = os.environ.get('DJANGO_MEDIA_ROOT',
 			    os.path.join((os.path.join(BASE_DIR, os.pardir)), "media"))
 MEDIA_MEMBERLISTS = os.path.join((os.path.join(BASE_DIR, os.pardir)), "media")
 
+# default primary key auto field type
+DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'
+
 # prevent large files from being unreadable by the server
 # see
 # https://stackoverflow.com/questions/51439689/django-nginx-error-403-forbidden-when-serving-media-files-over-some-size
@@ -55,8 +58,7 @@ INSTALLED_APPS = [
     'ludwigsburgalpin.apps.LudwigsburgalpinConfig',
     #'easy_select2',
     'djcelery_email',
-    'djcelery',
-    'jet',
+    #'jet',
     'django.contrib.admin',
     'django.contrib.auth',
     'django.contrib.contenttypes',
diff --git a/jdav_web/jdav_web/urls.py b/jdav_web/jdav_web/urls.py
index f2399ee..25dac59 100644
--- a/jdav_web/jdav_web/urls.py
+++ b/jdav_web/jdav_web/urls.py
@@ -13,12 +13,12 @@ Including another URLconf
     1. Import the include() function: from django.conf.urls import url, include
     2. Add a URL to urlpatterns:  url(r'^blog/', include('blog.urls'))
 """
-from django.conf.urls import url, include
+from django.urls import re_path, include
 from django.contrib import admin
 from django.conf.urls.static import static
 from django.conf.urls.i18n import i18n_patterns
 from django.conf import settings
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from django.views.generic.base import RedirectView
 
 urlpatterns = static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)
@@ -27,13 +27,13 @@ admin.site.index_title = _('Startpage')
 admin.site.site_header = 'Kompass'
 
 urlpatterns += i18n_patterns(
-    url(r'^kompass/', admin.site.urls),
-    url(r'^jet/', include('jet.urls', 'jet')), # Django JET URLS
-    url(r'^admin/', RedirectView.as_view(url='/kompass')),
-    url(r'^newsletter/', include('mailer.urls', namespace="mailer")),
-    url(r'^LBAlpin/Programm/2020', include('ludwigsburgalpin.urls',
-       namespace="ludwigsburgalpin")),
-    url(r'^$', include('startpage.urls')),
+    re_path(r'^kompass/', admin.site.urls),
+    #re_path(r'^jet/', include('jet.urls', 'jet')), # Django JET URLS
+    re_path(r'^admin/', RedirectView.as_view(url='/kompass')),
+    re_path(r'^newsletter/', include('mailer.urls', namespace="mailer")),
+    re_path(r'^LBAlpin/Programm/2020', include('ludwigsburgalpin.urls',
+            namespace="ludwigsburgalpin")),
+    re_path(r'^$', include('startpage.urls')),
 )
 
 # TODO: django serving from MEDIA_URL should be disabled in production stage
diff --git a/jdav_web/ludwigsburgalpin/urls.py b/jdav_web/ludwigsburgalpin/urls.py
index 6ff1be7..ae54963 100644
--- a/jdav_web/ludwigsburgalpin/urls.py
+++ b/jdav_web/ludwigsburgalpin/urls.py
@@ -1,9 +1,9 @@
-from django.conf.urls import url
+from django.urls import re_path
 
 from . import views
 
 app_name = "ludwigsburgalpin"
 urlpatterns = [
-    url(r'^$', views.index, name='index')
-    # url(r'^subscribe', views.subscribe, name='subscribe'),
+    re_path(r'^$', views.index, name='index')
+    # re_path(r'^subscribe', views.subscribe, name='subscribe'),
 ]
diff --git a/jdav_web/mailer/admin.py b/jdav_web/mailer/admin.py
index 0ca297a..f25cddb 100644
--- a/jdav_web/mailer/admin.py
+++ b/jdav_web/mailer/admin.py
@@ -1,6 +1,6 @@
 from django.contrib import admin, messages
 from django.contrib.admin import helpers
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from django.shortcuts import render
 from django.db import models
 from django import forms
diff --git a/jdav_web/mailer/apps.py b/jdav_web/mailer/apps.py
index 86c7e65..77c32f0 100644
--- a/jdav_web/mailer/apps.py
+++ b/jdav_web/mailer/apps.py
@@ -1,5 +1,5 @@
 from django.apps import AppConfig
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 class MailerConfig(AppConfig):
diff --git a/jdav_web/mailer/models.py b/jdav_web/mailer/models.py
index aeee21c..3317020 100644
--- a/jdav_web/mailer/models.py
+++ b/jdav_web/mailer/models.py
@@ -1,8 +1,8 @@
 from django.db import models
 from django.core.exceptions import ValidationError
 from django import forms
-from django.utils.translation import ugettext_lazy as _
-from django.utils.translation import ugettext
+from django.utils.translation import gettext_lazy as _
+from django.utils.translation import gettext
 from .mailutils import send, get_content, NOT_SENT, SENT, PARTLY_SENT, mail_root
 from utils import RestrictedFileField
 from jdav_web.celery import app
@@ -71,10 +71,12 @@ class Message(models.Model):
                                        blank=True)
     to_freizeit = models.ForeignKey('members.Freizeit',
                                     verbose_name=_('to freizeit'),
+                                    on_delete=models.CASCADE,
                                     blank=True,
                                     null=True)
     to_notelist = models.ForeignKey('members.MemberNoteList',
                                       verbose_name=_('to notes list'),
+                                      on_delete=models.CASCADE,
                                       blank=True,
                                       null=True)
     to_members = models.ManyToManyField('members.Member',
diff --git a/jdav_web/mailer/urls.py b/jdav_web/mailer/urls.py
index 63aee39..91f16e6 100644
--- a/jdav_web/mailer/urls.py
+++ b/jdav_web/mailer/urls.py
@@ -1,10 +1,10 @@
-from django.conf.urls import url
+from django.urls import re_path
 
 from . import views
 
 app_name = "mailer"
 urlpatterns = [
-    url(r'^$', views.index, name='index'),
+    re_path(r'^$', views.index, name='index'),
     # url(r'^subscribe', views.subscribe, name='subscribe'),
-    url(r'^unsubscribe', views.unsubscribe, name='unsubscribe'),
+    re_path(r'^unsubscribe', views.unsubscribe, name='unsubscribe'),
 ]
diff --git a/jdav_web/mailer/views.py b/jdav_web/mailer/views.py
index b8500d5..6530614 100644
--- a/jdav_web/mailer/views.py
+++ b/jdav_web/mailer/views.py
@@ -1,6 +1,6 @@
 from django.shortcuts import render
 from django import forms
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from django.urls import reverse
 from django.http import HttpResponseRedirect
 from .mailutils import send as send_mail, mail_root, get_unsubscribe_link
diff --git a/jdav_web/material/admin.py b/jdav_web/material/admin.py
index d1a946a..83e06c9 100644
--- a/jdav_web/material/admin.py
+++ b/jdav_web/material/admin.py
@@ -1,5 +1,5 @@
 from django.contrib import admin
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from django.contrib.admin import SimpleListFilter
 from django.db import models
 from django import forms
diff --git a/jdav_web/material/apps.py b/jdav_web/material/apps.py
index 047a5ab..c1ffb6e 100644
--- a/jdav_web/material/apps.py
+++ b/jdav_web/material/apps.py
@@ -1,5 +1,5 @@
 from django.apps import AppConfig
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 class MaterialConfig(AppConfig):
diff --git a/jdav_web/material/models.py b/jdav_web/material/models.py
index f6253e5..b545a9a 100644
--- a/jdav_web/material/models.py
+++ b/jdav_web/material/models.py
@@ -2,7 +2,7 @@ from datetime import datetime
 
 from django.db import models
 from django.utils import timezone
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 # maximum time in years of a material part until being replaced
 MAX_TIME_MATERIAL = 5
@@ -82,7 +82,7 @@ class MaterialPart(models.Model):
 class Ownership(models.Model):
     """Represents the connection between a MaterialPart and a Member"""
     material = models.ForeignKey(MaterialPart, on_delete=models.CASCADE)
-    owner = models.ForeignKey('members.Member', verbose_name=_('owner'))
+    owner = models.ForeignKey('members.Member', verbose_name=_('owner'), on_delete=models.CASCADE)
     count = models.IntegerField(_('count'), default=1)
 
     def __str__(self):
diff --git a/jdav_web/members/admin.py b/jdav_web/members/admin.py
index 89e72fa..bd52783 100644
--- a/jdav_web/members/admin.py
+++ b/jdav_web/members/admin.py
@@ -13,7 +13,7 @@ from django.contrib import admin, messages
 from django.contrib.admin import DateFieldListFilter
 from django.contrib.contenttypes.admin import GenericTabularInline
 from django.utils.html import format_html
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from django.db.models import TextField, ManyToManyField, ForeignKey, Count,\
     Sum, Case, Q, F, When, Value, IntegerField, Subquery, OuterRef
 from django.forms import Textarea, RadioSelect, TypedChoiceField
@@ -214,12 +214,10 @@ class ActivityCategoryAdmin(admin.ModelAdmin):
 
 
 class FreizeitAdminForm(forms.ModelForm):
-    difficulty = TypedChoiceField(Freizeit.difficulty_choices,
-                                  #widget=RadioSelect,
+    difficulty = TypedChoiceField(choices=Freizeit.difficulty_choices,
                                   coerce=int,
                                   label=_('Difficulty'))
-    tour_type = TypedChoiceField(Freizeit.tour_type_choices,
-                                 #widget=RadioSelect,
+    tour_type = TypedChoiceField(choices=Freizeit.tour_type_choices,
                                  coerce=int,
                                  label=_('Tour type'))
 
diff --git a/jdav_web/members/apps.py b/jdav_web/members/apps.py
index bc8b0c5..2839cc4 100644
--- a/jdav_web/members/apps.py
+++ b/jdav_web/members/apps.py
@@ -1,5 +1,5 @@
 from django.apps import AppConfig
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 class MembersConfig(AppConfig):
diff --git a/jdav_web/members/models.py b/jdav_web/members/models.py
index 852a85c..21ef23f 100644
--- a/jdav_web/members/models.py
+++ b/jdav_web/members/models.py
@@ -1,7 +1,7 @@
 from datetime import datetime
 import uuid
 from django.db import models
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 from django.utils import timezone
 from django.urls import reverse
 from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation
@@ -220,8 +220,8 @@ class OldMemberOnList(models.Model):
     """
     Connects members to a list of members.
     """
-    member = models.ForeignKey(Member, verbose_name=_('Member'))
-    memberlist = models.ForeignKey(MemberList)
+    member = models.ForeignKey(Member, verbose_name=_('Member'), on_delete=models.CASCADE)
+    memberlist = models.ForeignKey(MemberList, on_delete=models.CASCADE)
     comments = models.TextField(_('Comment'), default='', blank=True)
 
     def __str__(self):
@@ -236,7 +236,7 @@ class NewMemberOnList(models.Model):
     """
     Connects members to a list of members.
     """
-    member = models.ForeignKey(Member, verbose_name=_('Member'))
+    member = models.ForeignKey(Member, verbose_name=_('Member'), on_delete=models.CASCADE)
     content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE,
                                      default=ContentType('members', 'Freizeit').pk)
     object_id = models.PositiveIntegerField()
@@ -323,7 +323,7 @@ class Klettertreff(models.Model):
     location = models.CharField(_('Location'), default='', max_length=60)
     topic = models.CharField(_('Topic'), default='', max_length=60)
     jugendleiter = models.ManyToManyField(Member)
-    group = models.ForeignKey(Group, default='', verbose_name=_('Group'))
+    group = models.ForeignKey(Group, default='', verbose_name=_('Group'), on_delete=models.CASCADE)
 
     def __str__(self):
         return self.location + ' ' + self.date.strftime('%d.%m.%Y')
@@ -354,8 +354,8 @@ class Klettertreff(models.Model):
 
 class KlettertreffAttendee(models.Model):
     """Connects members to Klettertreffs."""
-    member = models.ForeignKey(Member, verbose_name=_('Member'))
-    klettertreff = models.ForeignKey(Klettertreff)
+    member = models.ForeignKey(Member, verbose_name=_('Member'), on_delete=models.CASCADE)
+    klettertreff = models.ForeignKey(Klettertreff, on_delete=models.CASCADE)
 
     def __str__(self):
         return str(self.member)
diff --git a/jdav_web/members/templatetags/overview_extras.py b/jdav_web/members/templatetags/overview_extras.py
index 8106749..5127167 100644
--- a/jdav_web/members/templatetags/overview_extras.py
+++ b/jdav_web/members/templatetags/overview_extras.py
@@ -8,10 +8,10 @@ def blToColor(bl):
     else:
         return 'red'
 
-@register.assignment_tag
+@register.simple_tag
 def has_attendee_wrapper(klettertreff, member):
     return blToColor(klettertreff.has_attendee(member))
 
-@register.assignment_tag
+@register.simple_tag
 def has_jugendleiter_wrapper(klettertreff, jugendleiter):
     return blToColor(klettertreff.has_jugendleiter(jugendleiter))
diff --git a/jdav_web/startpage/urls.py b/jdav_web/startpage/urls.py
index 9cb3403..29516d1 100644
--- a/jdav_web/startpage/urls.py
+++ b/jdav_web/startpage/urls.py
@@ -1,7 +1,7 @@
-from django.conf.urls import url
+from django.urls import re_path
 
 from . import views
 
 urlpatterns = [
-    url(r'^$', views.index, name='index')
+    re_path(r'^$', views.index, name='index')
 ]
diff --git a/jdav_web/utils.py b/jdav_web/utils.py
index 9408155..cc062c5 100644
--- a/jdav_web/utils.py
+++ b/jdav_web/utils.py
@@ -1,6 +1,6 @@
 from django.db import models
 from django.core.exceptions import ValidationError
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 class RestrictedFileField(models.FileField):
diff --git a/requirements.txt b/requirements.txt
deleted file mode 100644
index 7173d2d..0000000
--- a/requirements.txt
+++ /dev/null
@@ -1,29 +0,0 @@
-amqp==2.6.1
-anyjson==0.3.3
-billiard==3.6.4.0
-celery==4.4.1
-certifi==2021.5.30
-charset-normalizer==2.0.4
-Django==1.11
-django-appconf==1.0.3
-django-celery==3.3.0
-django-celery-email==1.1.5
-django-easy-select2==1.5.6
-django-jet==1.0.8
-django-multiselectfield==0.1.12
-idna==3.2
-importlib-metadata==4.8.1
-jet==1.0
-kombu==4.6.11
-mysqlclient==2.0.3
-Pillow==5.0.0
-pytz==2021.1
-redis==3.4.1
-requests==2.26.0
-six==1.16.0
-sqlparse==0.3.1
-typing-extensions==3.10.0.2
-urllib3==1.26.6
-vine==1.3.0
-XlsxWriter==1.2.8
-zipp==3.5.0