This article guides the reader through building an emergency notification system using Flask, HTMX, and Twilio Programmable Voice. The system allows users to input emergency messages via a web form, which are then sent as voice calls to predetermined recipient numbers. The development environment is set up with Python and virtual environments, and the necessary libraries such as Flask, HTMX, and Twilio Python module are installed. The application is built using Flask routes for handling HTTP requests and responses, while HTMX improves the user experience by handling form submissions asynchronously. Twilio Programmable Voice enables the delivery of voice notifications to specific phone numbers. The system also includes a .env file for storing environment variables securely. After building the application, the reader can test it by running the Flask application, navigating to the homepage, entering an emergency message, and clicking the "Send Notification" button. The console output will display log messages indicating that the notifications were sent successfully, and the recipient should receive a voice call with the emergency message.