Building a Gemini Live voice app with React, FastAPI and your own WebSocket protocol

2026-06-13 · Source: Towards AI - Medium · Field: Technology & Digital — Software Development & Engineering, Artificial Intelligence & Machine Learning · Depth: Intermediate, quick

Summary

This article details an architecture for building a Gemini Live voice application using a React frontend, a FastAPI backend, and a custom WebSocket protocol. Instead of connecting the browser directly to Google's Gemini Live service, the proposed method routes all communication through a self-owned backend. This approach addresses two key issues: preventing long-lived secrets from residing in the browser and decoupling Google's specific event names from the React components. By establishing a "product boundary" where the browser communicates with the backend via a custom protocol and the backend then interfaces with Gemini, all Gemini-specific logic is centralized into a single backend file, simplifying future SDK changes. The result is a functional voice app where users can interact with Gemini via audio.

Key takeaway

For AI Engineers or Software Engineers building Gemini Live voice applications, adopting a backend proxy architecture with a custom WebSocket protocol is crucial. This approach centralizes Gemini-specific logic in your FastAPI backend, significantly improving maintainability when Google updates its SDK or event shapes. Furthermore, it enhances security by preventing long-lived API secrets from being exposed in the browser, offering a more robust and scalable solution for production-ready voice apps.

Key insights

Decoupling a frontend from Gemini Live via a custom backend WebSocket protocol enhances security and maintainability.

Principles

• Establish a strong product boundary
• Centralize external API logic

Method

Implement a custom WebSocket protocol between the browser and a FastAPI backend, which then communicates with Gemini Live.

In practice

• Avoid long-lived secrets in the browser
• Decouple Google's event names from frontend
• Consolidate Gemini-specific logic in one backend file

Topics

• Gemini Live
• Voice Applications
• WebSocket Protocol
• FastAPI
• React
• Backend Proxy

Best for: AI Engineer, Software Engineer

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Editorial summary, takeaway, and curation by AIssential. Original article published by Towards AI - Medium.