diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 5e8dc43..43e9f17 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ on: [push, pull_request]
 jobs:
   run-tox:
     # The type of runner that the job will run on
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
@@ -20,7 +20,7 @@ jobs:
       - name: Setup python
         uses: actions/setup-python@v2
         with:
-          python-version: 3.6
+          python-version: 3.6.15
       - name: Install Tox
         run: pip install tox
       - name: Upgrade setuptools
diff --git a/.gitignore b/.gitignore
index 2be14f0..279c72e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,7 @@ __pycache__/*
 .*.swp
 */.ipynb_checkpoints/*
 .DS_Store
+.tags
 
 # Project files
 .ropeproject
@@ -48,3 +49,4 @@ MANIFEST
 
 # Per-project virtualenvs
 .venv*/
+.python-version
diff --git a/docs/conf.py b/docs/conf.py
index 1ba44b3..d40e17b 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -91,8 +91,8 @@
 master_doc = "index"
 
 # General information about the project.
-project = u"eiffel-graphql-api"
-copyright = u"2019, Axis Communications AB"
+project = "eiffel-graphql-api"
+copyright = "2019, Axis Communications AB"
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
@@ -240,7 +240,7 @@
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title, author, documentclass [howto/manual]).
 latex_documents = [
-    ("index", "user_guide.tex", u"Eiffel-graphql Documentation", u"", "manual"),
+    ("index", "user_guide.tex", "Eiffel-graphql Documentation", "", "manual"),
 ]
 
 # The name of an image file (relative to this directory) to place at the top of
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 1b50734..fa26b14 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,4 +1,5 @@
 sphinx<2
 pyscaffold==2.5.10
+mistune==0.8.4
 m2r==0.2.1
 sphinx-rtd-theme<0.5
diff --git a/src/eiffel_graphql_api/graphql/schemas/lib/generic.py b/src/eiffel_graphql_api/graphql/schemas/lib/generic.py
index f28b51f..e8e18a6 100644
--- a/src/eiffel_graphql_api/graphql/schemas/lib/generic.py
+++ b/src/eiffel_graphql_api/graphql/schemas/lib/generic.py
@@ -52,7 +52,7 @@ def load(name):
     :return: Json dictionary, starting from the properties key.
     :rtype: dict
     """
-    with open(os.path.join(BASE_JSON, name)) as json_file:
+    with open(os.path.join(BASE_JSON, name), encoding="utf-8") as json_file:
         data = json.load(json_file)
     return data.get("properties")
 
@@ -204,7 +204,7 @@ def key_names(key, override_name):
     # to change. By capitalizing just the first index and then attaching the rest
     # we achieve that.
     # Converts 'dataKey' to 'DataKey'.
-    cls_name = "{}{}".format(key[0].capitalize(), key[1:])
+    cls_name = f"{key[0].capitalize()}{key[1:]}"
     attribute_name = convert(key)
     return key, data_key, cls_name, attribute_name
 
@@ -236,7 +236,7 @@ def generate_array(key, value, override_name, data_dict):
     json_schema_to_graphql(cls_name, value, dictionary, override_name)
     obj = create_object_type(cls_name, dictionary, key)
     data_dict[attribute_name] = graphene.List(obj)
-    data_dict["resolve_{}".format(attribute_name)] = resolvers(graphene.List, data_key)
+    data_dict[f"resolve_{attribute_name}"] = resolvers(graphene.List, data_key)
 
 
 def generate_object(key, value, override_name, data_dict):
@@ -265,7 +265,7 @@ def generate_object(key, value, override_name, data_dict):
     json_schema_to_graphql(cls_name, value.get("properties"), dictionary, override_name)
     obj = create_object_type(cls_name, dictionary)
     data_dict[attribute_name] = graphene.Field(obj)
-    data_dict["resolve_{}".format(attribute_name)] = resolvers(graphene.Field, data_key)
+    data_dict[f"resolve_{attribute_name}"] = resolvers(graphene.Field, data_key)
 
 
 def generate_simple(key, graphene_type, override_name, data_dict):
@@ -287,7 +287,7 @@ def generate_simple(key, graphene_type, override_name, data_dict):
     """
     key, _, __, attribute_name = key_names(key, override_name)
     data_dict[attribute_name] = graphene_type()
-    data_dict["resolve_{}".format(attribute_name)] = resolvers(graphene_type, key)
+    data_dict[f"resolve_{attribute_name}"] = resolvers(graphene_type, key)
 
 
 def json_schema_to_graphql(
diff --git a/src/eiffel_graphql_api/graphql/schemas/schema.py b/src/eiffel_graphql_api/graphql/schemas/schema.py
index d36a8bd..99a05d8 100644
--- a/src/eiffel_graphql_api/graphql/schemas/schema.py
+++ b/src/eiffel_graphql_api/graphql/schemas/schema.py
@@ -29,7 +29,7 @@ class EiffelConnectionField(relay.ConnectionField):
 
     def __init__(self, field):
         """Initialize schema fields."""
-        field = "eiffel_graphql_api.graphql.schemas.events.{}".format(field)
+        field = f"eiffel_graphql_api.graphql.schemas.events.{field}"
         # pylint:disable=super-with-arguments
         super(EiffelConnectionField, self).__init__(field, search=graphene.String())
 
@@ -58,7 +58,7 @@ def generic_resolve(
         """Generically resolve a meta node for each eiffel object type."""
         # pylint:disable=protected-access
         obj = info.return_type.graphene_type._meta.node
-        collection = "Eiffel{}Event".format(obj)
+        collection = f"Eiffel{obj}Event"
 
         search = "{}" if search is None else search
         search = cls._clean_query(search)
@@ -82,8 +82,8 @@ def generic_resolve(
         NAME = NAME.replace("Eiffel", "")
         NAME = NAME.replace("Event", "")
         NAME = NAME.replace(".json", "")
-        CONNECTION_NAME = "{}Connection".format(NAME)
-        RESOLVE_NAME = "resolve_{}".format(convert(NAME))
+        CONNECTION_NAME = f"{NAME}Connection"
+        RESOLVE_NAME = f"resolve_{convert(NAME)}"
         SNAKE_NAME = convert(NAME)
         QUERY[SNAKE_NAME] = EiffelConnectionField(CONNECTION_NAME)
         QUERY[RESOLVE_NAME] = BaseQuery.generic_resolve
diff --git a/src/eiffel_graphql_api/storage.py b/src/eiffel_graphql_api/storage.py
index 182bf0c..9aa393f 100644
--- a/src/eiffel_graphql_api/storage.py
+++ b/src/eiffel_graphql_api/storage.py
@@ -31,10 +31,10 @@
 
 # Set environment variables from rabbitmq secrets in a kubernetes cluster.
 if os.path.isfile("/etc/rabbitmq/password"):
-    with open("/etc/rabbitmq/password", "r") as password:
+    with open("/etc/rabbitmq/password", "r", encoding="utf-8") as password:
         os.environ["RABBITMQ_PASSWORD"] = password.read()
 if os.path.isfile("/etc/rabbitmq/username"):
-    with open("/etc/rabbitmq/username", "r") as username:
+    with open("/etc/rabbitmq/username", "r", encoding="utf-8") as username:
         os.environ["RABBITMQ_USERNAME"] = username.read()
 
 
@@ -52,7 +52,7 @@ def parse_args(args):
     parser.add_argument(
         "--version",
         action="version",
-        version="eiffel-graphql-storage {ver}".format(ver=__version__),
+        version=f"eiffel-graphql-storage {__version__}",
     )
     parser.add_argument(
         "-v",
diff --git a/tests/test_events/activity_finished/test_activity_finished.py b/tests/test_events/activity_finished/test_activity_finished.py
index 098dc76..19cc943 100644
--- a/tests/test_events/activity_finished/test_activity_finished.py
+++ b/tests/test_events/activity_finished/test_activity_finished.py
@@ -110,10 +110,9 @@ def test_activity_finished_persistent_logs(self):
                     self.assertEqual(log.get("uri"), uri)
                     break
             else:
+                logs = data.get("activityPersistentLogs")
                 raise AssertionError(
-                    "{{'name': {}, 'uri': {}}} not in liveLogs: {}".format(
-                        name, uri, data.get("activityPersistentLogs")
-                    )
+                    f"{{'name': {name}, 'uri': {uri}}} not in liveLogs: {logs}"
                 )
 
     def test_activity_finished_link(self):
diff --git a/tox.ini b/tox.ini
index a8051a6..ef0dc28 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,9 +8,9 @@ envlist = py36,black,docs,pylint,pydocstyle
 
 [testenv]
 deps =
-    pytest
-    pytest-cov
-    mongomock
+    pytest==7.0
+    pytest-cov==4.0.0
+    mongomock==4.1.2
 setenv = MONGODB_CONNSTRING = mongodb://localhost:27017
          MONGODB_DATABASE = testing_eiffel_graphql_api
 commands =
@@ -19,27 +19,27 @@ basepython = python3.6
 
 [testenv:black]
 deps =
-    black
+    black==22.8.0
 commands =
     black --check --diff .
 
 [testenv:docs]
 deps =
-    -r docs/requirements.txt 
+    -r docs/requirements.txt
 commands =
     python setup.py docs
 
 [testenv:pylint]
 deps =
-    pylint
-    pytest
-    pytest-cov
-    mongomock
+    pylint==2.12.2
+    pytest==7.0
+    pytest-cov==4.0.0
+    mongomock==4.1.2
 commands =
     pylint src/eiffel_graphql_api tests
 
 [testenv:pydocstyle]
 deps =
-    pydocstyle
+    pydocstyle==6.3.0
 commands =
     pydocstyle .