diff --git a/flask_app/Dockerfile b/flask_app/Dockerfile
index b9820d6..91b44e1 100644
--- a/flask_app/Dockerfile
+++ b/flask_app/Dockerfile
@@ -1,9 +1,13 @@
-FROM python:3.6-slim-stretch
+FROM python:3.7-slim-buster
 
 RUN mkdir -pv /home/project/flask_app
 RUN mkdir -pv /var/ttn_tracker/ssl_certs
 
 WORKDIR /home/project/flask_app
+
+ENV DEBIAN_FRONTEND=noninteractive
+RUN apt update && apt install -y build-essential
+
 COPY requirements.txt /home/project/flask_app
 RUN pip install --upgrade pip
 RUN pip install --no-cache-dir -r requirements.txt
diff --git a/flask_app/app.py b/flask_app/app.py
index 7e5f627..7411530 100644
--- a/flask_app/app.py
+++ b/flask_app/app.py
@@ -9,6 +9,12 @@ from math import sqrt
 import os
 import requests
 from apscheduler.schedulers.background import BackgroundScheduler
+from dateutil.parser import parser
+from flask import Flask
+from flask import jsonify
+from flask import render_template
+from flask_sqlalchemy import SQLAlchemy
+
 from config import app_key
 from config import application
 from config import bing_api_key
@@ -19,11 +25,6 @@ from config import path_db
 from config import refresh_period_seconds
 from config import start_lat
 from config import start_lon
-from dateutil.parser import parser
-from flask import Flask
-from flask import jsonify
-from flask import render_template
-from flask_sqlalchemy import SQLAlchemy
 
 logging.basicConfig(level=logging.INFO, format='%(asctime)s %(message)s')
 logger = logging.getLogger(__name__)
diff --git a/flask_app/requirements.txt b/flask_app/requirements.txt
index 60e9b0d..28ab24d 100644
--- a/flask_app/requirements.txt
+++ b/flask_app/requirements.txt
@@ -1,6 +1,7 @@
-apscheduler
-python-dateutil
-gunicorn
-Flask==1.1.1
-flask_sqlalchemy
-requests
+apscheduler==3.7.0
+python-dateutil==2.8.1
+gunicorn==20.1.0
+Flask==1.1.2
+flask_sqlalchemy==2.5.1
+sqlalchemy==1.4.11
+requests==2.25.1
diff --git a/nginx/Dockerfile b/nginx/Dockerfile
index 1aa7494..22d13c9 100644
--- a/nginx/Dockerfile
+++ b/nginx/Dockerfile
@@ -1,4 +1,4 @@
-FROM nginx:1.15.9
+FROM nginx:1.19.10
 
 RUN rm /etc/nginx/nginx.conf
 COPY nginx.conf /etc/nginx/