diff --git a/kubemarine/admission.py b/kubemarine/admission.py
index 42897c116..8fde5dd10 100644
--- a/kubemarine/admission.py
+++ b/kubemarine/admission.py
@@ -16,7 +16,7 @@
 import os
 import uuid
 import re
-from typing import Dict, Any, List, Optional
+from typing import Dict, Any, List, Optional, Union
 
 import ruamel.yaml
 import yaml
@@ -899,22 +899,22 @@ def get_labels_to_ensure_profile(inventory: dict, profile: str) -> Dict[str, str
 def label_namespace_pss(cluster: KubernetesCluster, manage_type: str) -> None:
     first_control_plane = cluster.nodes["control-plane"].get_first_member()
     # set/delete labels on predifined plugins namsespaces
-    for namespace, profile in builtin.get_namespace_to_necessary_pss_profiles(cluster).items():
+    for ns_name, profile in builtin.get_namespace_to_necessary_pss_profiles(cluster).items():
         target_labels = get_labels_to_ensure_profile(cluster.inventory, profile)
         if manage_type in ["apply", "install"] and target_labels:
-            cluster.log.debug(f"Set PSS labels for profile {profile} on namespace {namespace}")
+            cluster.log.debug(f"Set PSS labels for profile {profile} on namespace {ns_name}")
             command = "kubectl label ns {namespace} {lk}={lv} --overwrite"
 
         else:  # manage_type == "delete" or default labels are not necessary
-            cluster.log.debug(f"Delete PSS labels from namespace {namespace}")
+            cluster.log.debug(f"Delete PSS labels from namespace {ns_name}")
             command = "kubectl label ns {namespace} {lk}- || true"
             target_labels = _get_default_labels(profile)
 
         for lk, lv in target_labels.items():
-            first_control_plane.sudo(command.format(namespace=namespace, lk=lk, lv=lv))
+            first_control_plane.sudo(command.format(namespace=ns_name, lk=lk, lv=lv))
 
     procedure_config = cluster.procedure_inventory["pss"]
-    namespaces = procedure_config.get("namespaces")
+    namespaces: List[Union[str, Dict[str, dict]]] = procedure_config.get("namespaces")
     # get the list of namespaces that should be labeled then set/delete labels
     if namespaces:
         default_modes = {}
diff --git a/kubemarine/core/connections.py b/kubemarine/core/connections.py
index 551a16dc1..2c18ac8ed 100644
--- a/kubemarine/core/connections.py
+++ b/kubemarine/core/connections.py
@@ -14,7 +14,7 @@
 import os
 from typing import Dict, List
 
-import fabric  # type: ignore[import]
+import fabric  # type: ignore[import-untyped]
 
 from kubemarine.core import static
 
diff --git a/kubemarine/core/executor.py b/kubemarine/core/executor.py
index a567ead76..b259ccfbd 100644
--- a/kubemarine/core/executor.py
+++ b/kubemarine/core/executor.py
@@ -22,8 +22,8 @@
 from types import TracebackType
 from typing import Tuple, List, Dict, Callable, Any, Optional, Union, OrderedDict, TypeVar, Type, Mapping, Iterable
 
-import fabric  # type: ignore[import]
-import fabric.transfer  # type: ignore[import]
+import fabric  # type: ignore[import-untyped]
+import fabric.transfer  # type: ignore[import-untyped]
 
 from concurrent.futures.thread import ThreadPoolExecutor
 
diff --git a/kubemarine/core/log.py b/kubemarine/core/log.py
index d5be2af20..6ae02a1ca 100644
--- a/kubemarine/core/log.py
+++ b/kubemarine/core/log.py
@@ -17,7 +17,7 @@
 import sys
 from abc import ABC, abstractmethod
 
-from pygelf import gelf, GelfTcpHandler, GelfUdpHandler, GelfTlsHandler, GelfHttpHandler  # type: ignore[import]
+from pygelf import gelf, GelfTcpHandler, GelfUdpHandler, GelfTlsHandler, GelfHttpHandler  # type: ignore[import-untyped]
 
 from copy import deepcopy
 from typing import Any, List, Optional, cast, Dict, Union
diff --git a/kubemarine/core/utils.py b/kubemarine/core/utils.py
index 811bfa8fd..54688d5bc 100755
--- a/kubemarine/core/utils.py
+++ b/kubemarine/core/utils.py
@@ -21,7 +21,7 @@
 import time
 import tarfile
 
-from typing import Tuple, Callable, List, TextIO, cast, Union, TypeVar, Dict
+from typing import Tuple, Callable, List, TextIO, cast, Union, TypeVar, Dict, Sequence
 
 import yaml
 import ruamel.yaml
@@ -40,9 +40,15 @@
 _T_contra = TypeVar("_T_contra", contravariant=True)
 
 
-class SupportsDunderLT(Protocol[_T_contra]):
+class SupportsAllComparisons(Protocol[_T_contra]):
     def __lt__(self, __other: _T_contra) -> bool: ...
 
+    def __gt__(self, __other: _T_contra) -> bool: ...
+
+    def __le__(self, __other: _T_contra) -> bool: ...
+
+    def __ge__(self, __other: _T_contra) -> bool: ...
+
 
 def do_fail(message: str = '', reason: Exception = None, hint: str = '', logger: log.EnhancedLogger = None) -> None:
 
@@ -381,7 +387,7 @@ def yaml_structure_preserver() -> ruamel.yaml.YAML:
     return ruamel_yaml
 
 
-def is_sorted(l: list, key: Callable = None) -> bool:
+def is_sorted(l: Sequence[str], key: Callable[[str], SupportsAllComparisons] = None) -> bool:
     """
     Check that the specified list is sorted.
 
@@ -394,7 +400,7 @@ def is_sorted(l: list, key: Callable = None) -> bool:
     return all(key(l[i]) <= key(l[i + 1]) for i in range(len(l) - 1))
 
 
-def map_sorted(map_: CommentedMap, key: Callable[[str], SupportsDunderLT] = None) -> CommentedMap:
+def map_sorted(map_: CommentedMap, key: Callable[[str], SupportsAllComparisons] = None) -> CommentedMap:
     """
     Check that the specified CommentedMap is sorted, or create new sorted map from it otherwise.
 
@@ -406,14 +412,14 @@ def map_sorted(map_: CommentedMap, key: Callable[[str], SupportsDunderLT] = None
         _key = key
     else:
         _key = lambda x: x
-    map_keys = list(map_)
+    map_keys: List[str] = list(map_)
     if not is_sorted(map_keys, key=_key):
         map_ = CommentedMap(sorted(map_.items(), key=lambda item: _key(item[0])))
 
     return map_
 
 
-def insert_map_sorted(map_: CommentedMap, k: str, v: object, key: Callable = None) -> None:
+def insert_map_sorted(map_: CommentedMap, k: str, v: object, key: Callable[[str], SupportsAllComparisons] = None) -> None:
     """
     Insert new item to the CommentedMap or update the value for the existing key.
     The map should be already sorted.
diff --git a/kubemarine/core/yaml_merger.py b/kubemarine/core/yaml_merger.py
index 97fd346dd..f1f715e62 100644
--- a/kubemarine/core/yaml_merger.py
+++ b/kubemarine/core/yaml_merger.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from deepmerge import Merger  # type: ignore[import]
+from deepmerge import Merger  # type: ignore[import-untyped]
 
 
 def is_list_extends(nxt: list) -> bool:
diff --git a/kubemarine/demo.py b/kubemarine/demo.py
index 42a5e9937..e554af8c0 100644
--- a/kubemarine/demo.py
+++ b/kubemarine/demo.py
@@ -22,7 +22,7 @@
 from copy import deepcopy
 from typing import List, Dict, Union, Any, Optional, Mapping, Iterable, IO, Tuple, cast
 
-import fabric  # type: ignore[import]
+import fabric  # type: ignore[import-untyped]
 import invoke
 
 from kubemarine import system, procedures
diff --git a/kubemarine/procedures/check_paas.py b/kubemarine/procedures/check_paas.py
index e57ed162c..feba185c4 100755
--- a/kubemarine/procedures/check_paas.py
+++ b/kubemarine/procedures/check_paas.py
@@ -39,7 +39,7 @@
 from kubemarine.kubernetes.deployment import Deployment
 from kubemarine.kubernetes.object import KubernetesObject
 from kubemarine.coredns import generate_configmap
-from deepdiff import DeepDiff  # type: ignore[import]
+from deepdiff import DeepDiff  # type: ignore[import-untyped]
 
 
 def services_status(cluster: KubernetesCluster, service_type: str) -> None:
diff --git a/kubemarine/resources/scripts/check_url_availability.py b/kubemarine/resources/scripts/check_url_availability.py
index f04564581..cf30a9dc7 100644
--- a/kubemarine/resources/scripts/check_url_availability.py
+++ b/kubemarine/resources/scripts/check_url_availability.py
@@ -22,7 +22,7 @@
 if major_version == 3:
     import urllib.request as urllib
 else:
-    import urllib2 as urllib  # type: ignore[import, no-redef]
+    import urllib2 as urllib  # type: ignore[import-not-found, no-redef]
 
 try:
     source = sys.argv[1]
diff --git a/pyproject.toml b/pyproject.toml
index 38d5a6f01..4f4c8dee2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -50,7 +50,7 @@ requires-python = ">=3.7"
 [project.optional-dependencies]
 ansible = ["ansible==7.0.*"]
 mypy = [
-    "mypy==1.3.*",
+    "mypy==1.7.*",
     "types-PyYAML==6.*",
     "types-invoke==1.*",
     "types-toml==0.*",
@@ -102,7 +102,7 @@ warn_unreachable = true
 # strict typing checks
 check_untyped_defs = true
 strict_equality = true
-strict_concatenate = true
+extra_checks = true
 disallow_subclassing_any = true
 disallow_untyped_decorators = true
 disallow_incomplete_defs = true