diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index a749856..327d5a0 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -105,8 +105,8 @@ jobs:
         run: |
           source .venv/bin/activate
           isort -m 9 --line-length 160 $MODULE_NAME tests --gitignore --check-only
-          # pylint $MODULE_NAME tests
+          pylint $MODULE_NAME tests
           docformatter --wrap-summaries 160 --wrap-descriptions 160 -cr $MODULE_NAME tests
           black --check $MODULE_NAME tests
           mypy -V
-          # mypy $MODULE_NAME tests
+          mypy $MODULE_NAME tests
diff --git a/clairvoyance/cli.py b/clairvoyance/cli.py
index 616d079..6a46137 100644
--- a/clairvoyance/cli.py
+++ b/clairvoyance/cli.py
@@ -45,7 +45,7 @@ def load_default_wordlist() -> List[str]:
         return [w.strip() for w in f.readlines() if w.strip()]
 
 
-async def blind_introspection(
+async def blind_introspection(  # pylint: disable=too-many-arguments
     url: str,
     logger: logging.Logger,
     wordlist: List[str],
diff --git a/clairvoyance/client.py b/clairvoyance/client.py
index a4f02d0..7a33013 100644
--- a/clairvoyance/client.py
+++ b/clairvoyance/client.py
@@ -8,7 +8,7 @@
 from clairvoyance.entities.interfaces import IClient
 
 
-class Client(IClient):
+class Client(IClient):  # pylint: disable=too-many-instance-attributes
     def __init__(
         self,
         url: str,
@@ -68,8 +68,8 @@ async def post(
                 return await response.json(content_type=None)
 
             except (
-                aiohttp.client_exceptions.ClientConnectionError,
-                aiohttp.client_exceptions.ClientPayloadError,
+                aiohttp.ClientConnectionError,
+                aiohttp.ClientPayloadError,
                 asyncio.TimeoutError,
                 json.decoder.JSONDecodeError,
             ) as e:
diff --git a/clairvoyance/entities/context.py b/clairvoyance/entities/context.py
index 04c7f30..1b1b8bf 100644
--- a/clairvoyance/entities/context.py
+++ b/clairvoyance/entities/context.py
@@ -10,11 +10,11 @@
 
 # Quick resolve the context variables using macros.
 config: Callable[..., IConfig] = (
-    lambda: config_ctx.get()
-)  # pylint: disable=unnecessary-lambda
+    lambda: config_ctx.get()  # pylint: disable=unnecessary-lambda
+)
 client: Callable[..., IClient] = (
-    lambda: client_ctx.get()
-)  # pylint: disable=unnecessary-lambda
+    lambda: client_ctx.get()  # pylint: disable=unnecessary-lambda
+)
 log: Callable[..., logging.Logger] = (
-    lambda: logger_ctx.get()
-)  # pylint: disable=unnecessary-lambda
+    lambda: logger_ctx.get()  # pylint: disable=unnecessary-lambda
+)
diff --git a/clairvoyance/entities/interfaces.py b/clairvoyance/entities/interfaces.py
index 722228c..6e16e9e 100644
--- a/clairvoyance/entities/interfaces.py
+++ b/clairvoyance/entities/interfaces.py
@@ -28,7 +28,9 @@ async def post(
         self,
         document: Optional[str],
         retries: int = 0,
-    ) -> Dict: ...
+    ) -> Dict:
+        pass
 
     @abstractmethod
-    async def close(self) -> None: ...
+    async def close(self) -> None:
+        pass
diff --git a/clairvoyance/graphql.py b/clairvoyance/graphql.py
index 9057221..5041d59 100644
--- a/clairvoyance/graphql.py
+++ b/clairvoyance/graphql.py
@@ -11,10 +11,10 @@ class Schema:
 
     def __init__(
         self,
-        query_type: str = None,
-        mutation_type: str = None,
-        subscription_type: str = None,
-        schema: Dict[str, Any] = None,
+        query_type: Optional[str] = None,
+        mutation_type: Optional[str] = None,
+        subscription_type: Optional[str] = None,
+        schema: Optional[Dict[str, Any]] = None,
     ):
         if schema:
             self._schema = {
@@ -142,7 +142,7 @@ def get_path_from_root(
 
     def get_type_without_fields(
         self,
-        ignored: Set[str] = None,
+        ignored: Optional[Set[str]] = None,
     ) -> str:
         """Gets the type without a field."""
         ignored = ignored or set()
@@ -331,7 +331,7 @@ def __init__(
         self,
         name: str,
         typeref: Optional[TypeRef],
-        args: List[InputValue] = None,
+        args: Optional[List[InputValue]] = None,
     ):
         if not typeref:
             raise ValueError(f"Can't create {name} Field from {typeref} TypeRef.")
@@ -367,7 +367,7 @@ def __init__(
         self,
         name: str = "",
         kind: str = "",
-        fields: List[Field] = None,
+        fields: Optional[List[Field]] = None,
     ):
         self.name = name
         self.kind = kind
diff --git a/clairvoyance/oracle.py b/clairvoyance/oracle.py
index 3d2c8a6..e91407b 100644
--- a/clairvoyance/oracle.py
+++ b/clairvoyance/oracle.py
@@ -422,7 +422,6 @@ async def __probation(document: str) -> Optional[graphql.TypeRef]:
                     error["message"],
                     context,
                 )
-
             log().debug(f'get_typeref("{error["message"]}", "{context}") -> {typeref}')
             if typeref:
                 return typeref
@@ -582,7 +581,7 @@ async def explore_field(
 async def clairvoyance(
     wordlist: List[str],
     input_document: str,
-    input_schema: Dict[str, Any] = None,
+    input_schema: Optional[Dict[str, Any]] = None,
 ) -> str:
 
     log().debug(f"input_document = {input_document}")
diff --git a/tests/graphql_test.py b/tests/graphql_test.py
index 2a53986..4008f0b 100644
--- a/tests/graphql_test.py
+++ b/tests/graphql_test.py
@@ -60,9 +60,9 @@ class TestPost(aiounittest.AsyncTestCase):
     def setUpClass(cls) -> None:
         Client("http://localhost:8000/graphql")
 
-        cls._unstable = subprocess.Popen(
+        cls._unstable = subprocess.Popen(  # pylint: disable=consider-using-with
             ["python3", "tests/server/unstable.py"]
-        )  # pylint: disable=consider-using-with
+        )
         time.sleep(1)
 
     @classmethod
diff --git a/tests/oracle_test.py b/tests/oracle_test.py
index a255598..e0cba17 100644
--- a/tests/oracle_test.py
+++ b/tests/oracle_test.py
@@ -287,9 +287,9 @@ class TestProbeTypename(aiounittest.AsyncTestCase):
     def setUpClass(cls) -> None:
         Client("http://localhost:8081/graphql")
 
-        cls._unstable = subprocess.Popen(
+        cls._unstable = subprocess.Popen(  # pylint: disable=consider-using-with
             ["python3", "tests/server/graphql.py"]
-        )  # pylint: disable=consider-using-with
+        )
         time.sleep(1)
 
     @classmethod
diff --git a/tests/server/graphql.py b/tests/server/graphql.py
index 70349ae..1cb4cb5 100644
--- a/tests/server/graphql.py
+++ b/tests/server/graphql.py
@@ -1,5 +1,6 @@
 import http.server
 import json
+from typing import Optional
 
 
 class UnstableHTTPRequestHandler(http.server.BaseHTTPRequestHandler):
@@ -24,7 +25,7 @@ def log_message(self, format, *args) -> None:  # type: ignore[no-untyped-def] #
         pass
 
 
-def main(port: int = None) -> None:
+def main(port: Optional[int] = None) -> None:
     port = port or 8081
     with http.server.HTTPServer(("", port), UnstableHTTPRequestHandler) as httpd:
         httpd.serve_forever()
diff --git a/tests/server/unstable.py b/tests/server/unstable.py
index b0bfd32..4c66b96 100644
--- a/tests/server/unstable.py
+++ b/tests/server/unstable.py
@@ -1,6 +1,7 @@
 import http.server
 import json
 import os
+from typing import Optional
 
 
 class UnstableHTTPRequestHandler(http.server.BaseHTTPRequestHandler):
@@ -23,7 +24,7 @@ def log_message(self, format, *args) -> None:  # type: ignore[no-untyped-def] #
         pass
 
 
-def main(port: int = None) -> None:
+def main(port: Optional[int] = None) -> None:
     port = port or 8000
     with http.server.HTTPServer(("", port), UnstableHTTPRequestHandler) as httpd:
         httpd.serve_forever()
diff --git a/tests/system.py b/tests/system.py
index 1037c8d..b71db1e 100644
--- a/tests/system.py
+++ b/tests/system.py
@@ -45,7 +45,7 @@ def setUpClass(cls) -> None:
     def query_type(self) -> Any:
         query_type = self.get_type(self.schema["queryType"]["name"])
         if not query_type:
-            raise Exception("Schema don't contain query type")
+            raise RuntimeError("Schema don't contain query type")
 
         return query_type
 
@@ -56,7 +56,7 @@ def get_type(self, name: str) -> Optional[Dict[str, Any]]:
 
         return None
 
-    def test_validate_wordlist(self):
+    def test_validate_wordlist(self) -> None:
         self.assertIn(b"Removed 1 items from wordlist", self.clairvoyance.stderr)
 
     def test_found_root_type_names(self) -> None: