diff --git a/.eslintrc.json b/.eslintrc.json
index 7ea5a2b5..113aae57 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -376,7 +376,13 @@
     "import/no-named-as-default": "warn",
     "import/no-named-as-default-member": "warn",
     "import/no-deprecated": "warn",
-    "import/no-extraneous-dependencies": "warn",
+    "import/no-extraneous-dependencies": [
+      "warn",
+      {
+        "devDependencies": true,
+        "packageDir": "."
+      }
+    ],
     "import/no-mutable-exports": "warn",
     "import/unambiguous": "off",
     "import/no-commonjs": "off",
diff --git a/Makefile.config b/Makefile.config
index 9a9b91db..0752ddf9 100644
--- a/Makefile.config
+++ b/Makefile.config
@@ -5,7 +5,7 @@ CLIENT_PORT = 3000
 export REACT_APP_API_URL = http://$(HOST):$(API_PORT)
 export FLASK_APP = $(PWD)/mpwo_api/server.py
 export APP_SETTINGS=mpwo_api.config.DevelopmentConfig
-export FLASK_DEBUG = 1
+export FLASK_ENV=development
 export TEST_URL = http://$(HOST):$(CLIENT_PORT)
 export REQUIREMENTS = $(PWD)/mpwo_api/requirements.txt
 export DATABASE_URL = postgres://mpwo:mpwo@$(HOST):5432/mpwo
diff --git a/mpwo_api/mpwo_api/activities/activities.py b/mpwo_api/mpwo_api/activities/activities.py
index 5281d6a7..e14f10c6 100644
--- a/mpwo_api/mpwo_api/activities/activities.py
+++ b/mpwo_api/mpwo_api/activities/activities.py
@@ -153,17 +153,12 @@ def delete_sport(auth_user_id, sport_id):
     try:
         sport = Sport.query.filter_by(id=sport_id).first()
         if sport:
-            db.session.query(Sport).filter_by(id=sport_id).delete()
+            db.session.delete(sport)
             db.session.commit()
             response_object = {
-                'status': 'no content',
-                'data': {
-                    'sports': sports_list
-                }
+                'status': 'no content'
             }
             code = 204
-            print('OK')
-            print(response_object)
         else:
             response_object = {
                 'status': 'not found',
diff --git a/mpwo_api/mpwo_api/config.py b/mpwo_api/mpwo_api/config.py
index 0b6d8291..87d93744 100644
--- a/mpwo_api/mpwo_api/config.py
+++ b/mpwo_api/mpwo_api/config.py
@@ -20,8 +20,7 @@ class BaseConfig:
 class DevelopmentConfig(BaseConfig):
     """Development configuration"""
     DEBUG = True
-    SQLALCHEMY_DATABASE_URI = \
-        os.environ.get('DATABASE_URL')
+    SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_URL')
     SECRET_KEY = 'development key'
     USERNAME = 'admin'
     PASSWORD = 'default'
@@ -32,8 +31,7 @@ class TestingConfig(BaseConfig):
     """Testing configuration"""
     DEBUG = True
     TESTING = True
-    SQLALCHEMY_DATABASE_URI = \
-        os.environ.get('DATABASE_TEST_URL')
+    SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_TEST_URL')
     SECRET_KEY = 'test key'
     USERNAME = 'admin'
     PASSWORD = 'default'
diff --git a/mpwo_api/mpwo_api/tests/conftest.py b/mpwo_api/mpwo_api/tests/conftest.py
index dff9af00..2f4f3506 100644
--- a/mpwo_api/mpwo_api/tests/conftest.py
+++ b/mpwo_api/mpwo_api/tests/conftest.py
@@ -1,11 +1,15 @@
+import os
+
 import pytest
 from mpwo_api import create_app, db
 
+os.environ["FLASK_ENV"] = 'testing'
+os.environ["APP_SETTINGS"] = 'mpwo_api.config.TestingConfig'
+
 
 @pytest.fixture
 def app():
     app = create_app()
-    app.config.from_object('mpwo_api.config.TestingConfig')
     with app.app_context():
         db.create_all()
         yield app
diff --git a/mpwo_client/src/components/Admin/generic/AdminDetail.jsx b/mpwo_client/src/components/Admin/generic/AdminDetail.jsx
index 068b2bfb..a62fbb74 100644
--- a/mpwo_client/src/components/Admin/generic/AdminDetail.jsx
+++ b/mpwo_client/src/components/Admin/generic/AdminDetail.jsx
@@ -1,7 +1,6 @@
 import React from 'react'
 import { Helmet } from 'react-helmet'
 import { connect } from 'react-redux'
-import { Link } from 'react-router-dom'
 
 import { deleteData, updateData } from '../../../actions/index'
 
diff --git a/mpwo_client/src/components/Admin/generic/AdminPage.jsx b/mpwo_client/src/components/Admin/generic/AdminPage.jsx
index a0966b7d..3936d4ec 100644
--- a/mpwo_client/src/components/Admin/generic/AdminPage.jsx
+++ b/mpwo_client/src/components/Admin/generic/AdminPage.jsx
@@ -39,6 +39,7 @@ export default function AdminPage(props) {
                   </thead>
                   <tbody>
                     { results.map((result, idx) => (
+                      // eslint-disable-next-line react/no-array-index-key
                       <tr key={idx}>
                         { Object.keys(result).map(key => {
                           if (key === 'id') {
diff --git a/package.json b/package.json
index 64573c82..b22eeede 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
     "build": "cd mpwo_client && react-scripts build",
     "test": "cd mpwo_client && testcafe firefox e2e",
     "eject": "cd mpwo_client && react-scripts eject",
-    "lint": "eslint --cache --ext .jsx --ext .js mpwo/src"
+    "lint": "eslint --cache --ext .jsx --ext .js mpwo_client/src"
   },
   "devDependencies": {
     "babel-eslint": "^8.0.3",