diff --git a/requirements/dev.in b/requirements/dev.in
index 84ed92b77ed04bf36196fe6a119e21d103be2b11..731ed01e1af84c1be4f8cb4402535866e70e6a82 100644
--- a/requirements/dev.in
+++ b/requirements/dev.in
@@ -8,15 +8,11 @@ dtale>=1.34.0
 Flask>=1.1.2
 Flask-SQLAlchemy>=2.4.4
 Flask-Cors>=3.0.10
-Flask-BS4==4.5.3.0
+Flask-BS4>=4.5.3.0,<5.0.0.0
 SQLAlchemy>=1.3.23
 psycopg2>=2.8.6
 wget>=3.2
 celery[redis]>=5.0.5
-Flask-PluginKit
-Flask-ResponseBuilder
-plantuml-creator
-plantuml-markdown
 flask-resources==0.6.0
 Flask-PluginKit>=3.6.0
 Flask-ResponseBuilder>=2.0.12
diff --git a/requirements/tests.in b/requirements/tests.in
index 3bba66b31b516802c120d0fab6bef57e978ed0f3..61ed7fa0e624c55a048525c35916f89e98f9b759 100644
--- a/requirements/tests.in
+++ b/requirements/tests.in
@@ -1,12 +1,15 @@
+pytoml
 pytest==5.3.2
 pytest-runner==5.3.0
+pytest-flask
+pytest-flask-sqlalchemy
+pytest-mock
+pytest-celery
 blinker
 greenlet
 python-dotenv
-pytest-flask
 test-flask
 unittest2>=1.0.0
 extras>=1.0.0
 fixtures>=1.3.0
 python-mimeparse
-pytoml
diff --git a/setup.py b/setup.py
index bfdde35552afe6431d9a3c435dd6658e68bdedc8..d694f0208cd460c15822cd23eb1989da048fc70c 100644
--- a/setup.py
+++ b/setup.py
@@ -64,7 +64,10 @@ requires_test = [
     "python-dotenv==0.15.0",
     "test-flask==0.2.0",
     "wcwidth==0.2.5",
-    "werkzeug==1.0.1"
+    "werkzeug==1.0.1",
+    "pytest_celery>=0.0.0a1",
+    "pytest-flask-sqlalchemy-1.0.2",
+    "pytest-mock-3.5.1"
 ]
 
 requires_docs = [
diff --git a/tests/conftest.py b/tests/conftest.py
index da2cabc147d01c14fef08aa95bba113814d7920c..40f1f65b35924eaa332d85b29655bbe799e6d72d 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -3,6 +3,8 @@ import tempfile
 import pytest
 from database import create_app, create_db_test, create_admin
 
+pytest_plugins = ("celery.contrib.pytest", )
+
 
 @pytest.fixture
 def app():
diff --git a/tests/test_mq.py b/tests/test_mq.py
index a33905906322e145c274714c4b582d4ae0f86f9d..e10769a6ca156de204374c4b2e09918cc122d86d 100644
--- a/tests/test_mq.py
+++ b/tests/test_mq.py
@@ -5,6 +5,7 @@ import covid19_worker
 from covid19 import app
 from covid19.blueprints.application.application_workers import celery, run_mq
 
+# Celery: https://docs.celeryproject.org/en/stable/userguide/index.html
 
 # ---------------------------------------------------------------------------------
 #  MAIN
diff --git a/tests/test_web.py b/tests/test_web.py
index 657bfe442e03b1c567b4d6e33fb13817604374f3..c5a38af4303dc10dc3649b81c8870cc90639afd2 100644
--- a/tests/test_web.py
+++ b/tests/test_web.py
@@ -4,6 +4,22 @@ import covid19.blueprints.application.application_views
 
 from covid19 import run_web
 
+# https://realpython.com/pytest-python-testing/
+# https://www.guru99.com/pytest-tutorial.html
+#
+#
+# https://docs.pytest.org/en/stable/
+# https://www.jetbrains.com/help/pycharm/pytest.html
+# https://docs.celeryproject.org/en/stable/userguide/testing.html
+#
+# https://werkzeug.palletsprojects.com/en/1.0.x/test/#werkzeug.test.Client
+# https://flask.palletsprojects.com/en/1.1.x/testing/
+# https://flask.palletsprojects.com/en/1.1.x/tutorial/tests/
+#
+# https://flask.palletsprojects.com/en/1.1.x/tutorial/install/
+# https://packaging.python.org/tutorials/packaging-projects/
+
+
 # ---------------------------------------------------------------------------------
 #  MAIN
 # ---------------------------------------------------------------------------------