diff --git a/.github/workflows/actions.yml b/.github/workflows/actions.yml
index 04d3694..239a2a4 100644
--- a/.github/workflows/actions.yml
+++ b/.github/workflows/actions.yml
@@ -26,6 +26,8 @@ jobs:
         run: make check-format
       - name: Run linter
         run: make lint
+      - name: Type check
+        run: make typecheck
       - name: Security audit
         run: make audit
 
@@ -49,5 +51,7 @@ jobs:
         run: make check-format
       - name: Run linter
         run: make lint
+      - name: Type check
+        run: make typecheck
       - name: Security audit
         run: make audit
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d0341fc..ec13370 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -27,6 +27,7 @@ and this project adheres to
 - CI: use Makefile targets in Windows job and add sequential per-commit
   testing triggered by the ci:per-commit label ([3967e42], [#66])
 - Remove duplicated lint-shell target in Makefile ([a652654], [#67])
+- Add mypy type checking to CI workflow ([6b9a3db], [#42])
 - Migrate from Poetry to uv ([14bc55e], [#65])
 
 ## [0.1.10] - 2024-12-XX
@@ -64,6 +65,7 @@ and this project adheres to
 [0.1.9]: https://github.com/LeakIX/LeakIXClient-Python/releases/tag/v0.1.9
 
 <!-- Commit links -->
+[6b9a3db]: https://github.com/LeakIX/LeakIXClient-Python/commit/6b9a3db
 [d111628]: https://github.com/LeakIX/LeakIXClient-Python/commit/d111628
 [df916e5]: https://github.com/LeakIX/LeakIXClient-Python/commit/df916e5
 [14bc55e]: https://github.com/LeakIX/LeakIXClient-Python/commit/14bc55e
@@ -82,4 +84,5 @@ and this project adheres to
 [#66]: https://github.com/LeakIX/LeakIXClient-Python/pull/66
 [#65]: https://github.com/LeakIX/LeakIXClient-Python/issues/65
 [#67]: https://github.com/LeakIX/LeakIXClient-Python/issues/67
+[#42]: https://github.com/LeakIX/LeakIXClient-Python/issues/42
 [#68]: https://github.com/LeakIX/LeakIXClient-Python/pull/68
diff --git a/leakix/client.py b/leakix/client.py
index 29353f7..067d0e2 100644
--- a/leakix/client.py
+++ b/leakix/client.py
@@ -2,7 +2,7 @@
 import json
 from enum import Enum
 from importlib.metadata import version
-from typing import Any
+from typing import Any, cast
 
 import requests
 from l9format import l9format
@@ -99,9 +99,7 @@ def get(
         if queries is None or len(queries) == 0:
             serialized_query = EmptyQuery().serialize()
         else:
-            serialized_query = [q.serialize() for q in queries]
-            serialized_query = " ".join(serialized_query)
-            serialized_query = f"{serialized_query}"
+            serialized_query = " ".join(q.serialize() for q in queries)
         url = f"{self.base_url}/search"
         r = self.__get(
             url=url,
@@ -149,7 +147,7 @@ def get_host(self, ipv4: str) -> AbstractResponse:
         r = self.__get(url, params=None)
         if r.is_success():
             response_json = r.json()
-            formatted_result = HostResult.from_dict(response_json)
+            formatted_result = cast(HostResult, HostResult.from_dict(response_json))
             response_json = {
                 "services": formatted_result.Services,
                 "leaks": formatted_result.Leaks,
@@ -190,9 +188,7 @@ def bulk_export(self, queries: list[Query] | None = None) -> AbstractResponse:
         if queries is None or len(queries) == 0:
             serialized_query = EmptyQuery().serialize()
         else:
-            serialized_query = [q.serialize() for q in queries]
-            serialized_query = " ".join(serialized_query)
-            serialized_query = f"{serialized_query}"
+            serialized_query = " ".join(q.serialize() for q in queries)
         params = {"q": serialized_query}
         r = requests.get(url, params=params, headers=self.headers, stream=True)
         if r.status_code == 200:
@@ -228,9 +224,7 @@ def bulk_service(self, queries: list[Query] | None = None) -> AbstractResponse:
         if queries is None or len(queries) == 0:
             serialized_query = EmptyQuery().serialize()
         else:
-            serialized_query = [q.serialize() for q in queries]
-            serialized_query = " ".join(serialized_query)
-            serialized_query = f"{serialized_query}"
+            serialized_query = " ".join(q.serialize() for q in queries)
         params = {"q": serialized_query}
         r = requests.get(url, params=params, headers=self.headers, stream=True)
         if r.status_code == 200:
diff --git a/pyproject.toml b/pyproject.toml
index a769f1e..648c835 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -16,6 +16,7 @@ dev = [
     "pytest",
     "pytest-cov",
     "mypy",
+    "types-requests",
     "requests-mock",
     "ruff",
     "pip-audit",