A Python developer transformed a local PDF merging script into a web application to make it accessible for non-technical family members. Initially, the developer used a simple Python script with PyPDF for merging PDF files but found it tedious to handle repetitive requests from family. To address this, the developer built a web app using Django and Django Rest Framework for the backend and React.js for the frontend. The app features a RESTful API that allows users to upload, merge, and download PDF files while ensuring authentication and data validation. The backend is designed to be frontend-agnostic, allowing for future scalability, and the app is deployed on a local server using Docker. The developer employed JWT for authentication and incorporated user permissions to secure the app. Frontend authentication is managed via browser cookies storing access and refresh tokens. The project serves as a practical example of how a simple script can evolve into a full-fledged application, offering insights into the lifecycle of app development, from idea to deployment.