There is a persistent misconception that pure client-side applications (Single Page Applications, SPAs) operating without their own dedicated backend and hosted on free hosting platforms like GitHub Pages are doomed to isolation. It is widely assumed that their absolute limit is storing user data in the current browser's localStorage or IndexedDB.
This approach imposes serious limitations: users cannot synchronize their data across devices, and clearing the cache or switching browsers completely erases all important information.
However, modern Serverless architecture and the concept of BaaS (Backend-as-a-Service) completely change the rules. A client-side application is fully capable of communicating directly with third-party databases, providing seamless synchronization, user registration, and secure data storage.
An excellent real-world implementation of this approach is the open-source project Traliran AI Hub (demo available at traliran.github.io). In this article, using the project's source code, we will break down how to build a flexible, cross-platform data synchronization system directly from the browser.
Solution Architecture: A Bridge Between Browser and Cloud
