diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
new file mode 100644
index 0000000..5a78f71
--- /dev/null
+++ b/.github/workflows/main.yml
@@ -0,0 +1,17 @@
+name: flake8 Lint
+
+on: [push, pull_request]
+
+jobs:
+  flake8-lint:
+    runs-on: ubuntu-latest
+    name: Lint
+    steps:
+      - name: Check out source repository
+        uses: actions/checkout@v3
+      - name: Set up Python environment
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.11"
+      - name: flake8 Lint
+        uses: py-actions/flake8@v2
diff --git a/backend/routers/manager.py b/backend/routers/manager.py
index deeca47..6ec1bf3 100644
--- a/backend/routers/manager.py
+++ b/backend/routers/manager.py
@@ -118,7 +118,10 @@ def change_subordinate_password():
 
         user_account = request.form["account"]
         new_password = request.form["password"]
-        if SubordinateModel.find_by_account_and_subordinate(account=account, subordinate=user_account) is None:
+        if SubordinateModel.find_by_account_and_subordinate(
+            account=account,
+            subordinate=user_account,
+        ) is None:
             return {'msg': 'User does not exist'}, HTTPStatus.FORBIDDEN
 
         if UserModel.find_by_account(account=user_account) is None:
@@ -152,7 +155,10 @@ def manager_upload_gait_csv():
         request_form = request.form.to_dict()
         target_account = request_form['account']  # should be subordinate
         request_form.pop('account', None)
-        if SubordinateModel.find_by_account_and_subordinate(account=account, subordinate=target_account) is None:
+        if SubordinateModel.find_by_account_and_subordinate(
+            account=account,
+            subordinate=target_account,
+        ) is None:
             return {'msg': 'User does not exist'}, HTTPStatus.FORBIDDEN
 
         form_data = request_schema.load(request_form)
@@ -213,7 +219,10 @@ def manager_request_results():
             return {'msg': 'User does not exist'}, HTTPStatus.FORBIDDEN
 
         target_account = request.form['account']
-        if SubordinateModel.find_by_account_and_subordinate(account=account, subordinate=target_account) is None:
+        if SubordinateModel.find_by_account_and_subordinate(
+            account=account,
+            subordinate=target_account,
+        ) is None:
             return {'msg': 'User does not exist'}, HTTPStatus.FORBIDDEN
 
         request_objects = RequestModel.find_by_account_and_sort_by_exp_date(account=target_account)
@@ -326,7 +335,7 @@ def manager_request_report_download():
                     stage = profile_object.__dict__['stage']
                     dominantSide = profile_object.__dict__['dominantSide']
                     lded = profile_object.__dict__['lded']
-                    ss = f'{target_account},{name},{gender},{birthday},{diagnose},{stage},{dominantSide},{lded},'
+                    ss = f'{target_account},{name},{gender},{birthday},{diagnose},{stage},{dominantSide},{lded},'  # noqa
 
                 orders = [
                     'stride length',
@@ -340,7 +349,9 @@ def manager_request_report_download():
                 request_objects = RequestModel.find_by_account(account=target_account)
                 for request_object in request_objects:
                     sss = ss + f'{request_object.__dict__["date"].strftime("%Y-%m-%d")}'
-                    result_objects = ResultModel.find_by_requestUUID(requestUUID=request_object.__dict__["submitUUID"])
+                    result_objects = ResultModel.find_by_requestUUID(
+                        requestUUID=request_object.__dict__["submitUUID"],
+                    )
                     collections = {
                         'stride length': 0,
                         'stride width': 0,
@@ -400,7 +411,10 @@ def manager_get_user_profile():
             return {'msg': 'User does not exist'}, HTTPStatus.FORBIDDEN
 
         target_account = request.form['account']
-        if SubordinateModel.find_by_account_and_subordinate(account=account, subordinate=target_account) is None:
+        if SubordinateModel.find_by_account_and_subordinate(
+            account=account,
+            subordinate=target_account,
+        ) is None:
             return {'msg': 'User does not exist'}, HTTPStatus.FORBIDDEN
 
         profile_object = ProfileModel.find_latest_by_account(account=target_account)
diff --git a/backend/setup.cfg b/backend/setup.cfg
index ccece61..59969e7 100644
--- a/backend/setup.cfg
+++ b/backend/setup.cfg
@@ -26,7 +26,8 @@ omit = *tests/*, **/_saferepr.py
 branch = True
 
 [flake8]
-max-line-length = 119
+max-line-length = 100
+max-complexity = 10
 ignore =
     # Do not assign a lambda expression, use a def (https://www.flake8rules.com/rules/E731.html)
     E731,
@@ -38,6 +39,7 @@ ignore =
     D,DAR,RST
     # Found commented out code, not ready...
     E800
+    C901
 
 exclude =
     .git,
@@ -49,6 +51,7 @@ exclude =
     build/
     # sphinx docs
     docs/
+    algorithms/gait_basic
 
 per-file-ignores =
     # allow non-optimized or insecure code in tests
diff --git a/backend/wsgi.py b/backend/wsgi.py
index d099b92..58d2795 100644
--- a/backend/wsgi.py
+++ b/backend/wsgi.py
@@ -1 +1,2 @@
+# flake8: noqa
 from app import app
diff --git a/setup.cfg b/setup.cfg
new file mode 100644
index 0000000..507eefe
--- /dev/null
+++ b/setup.cfg
@@ -0,0 +1,5 @@
+[flake8]
+max-line-length = 100
+extend-ignore = C901
+exclude = backend/algorithms/gait_basic
+max-complexity = 10
\ No newline at end of file