# Authentication made easy: Building a secure e-commerce shopping cart with Firebase

DevFeed: [Authentication made easy: Building a secure e-commerce shopping cart with Firebase](<https://devfeed.tech/articles/authentication-made-easy-building-a-secure-e-commerce-shopping-cart-with-firebase-16676.md>)

Original publisher: [Read original article](<https://firebase.blog/posts/2026/09/secure-shopping-cart-firebase>)

Author: Karl Weinmeister

Published: 2026-09-01T00:00:00Z

Content type: tutorial

Language: en

Sources: [Firebase Blog](<https://devfeed.tech/sources/firebase-blog.md>)

Topics: [Authentication](<https://devfeed.tech/topics/authentication.md>), [Firebase](<https://devfeed.tech/topics/firebase.md>), [Firestore](<https://devfeed.tech/topics/firestore.md>), [Authorization](<https://devfeed.tech/topics/authorization.md>), [Security](<https://devfeed.tech/topics/security.md>)

Tags: [authentication](<https://devfeed.tech/tags/authentication.md>), [cloud-run](<https://devfeed.tech/tags/cloud-run.md>), [e-commerce](<https://devfeed.tech/tags/e-commerce.md>), [firebase](<https://devfeed.tech/tags/firebase.md>), [firestore](<https://devfeed.tech/tags/firestore.md>), [security-rules](<https://devfeed.tech/tags/security-rules.md>), [shopping](<https://devfeed.tech/tags/shopping.md>), [tutorials](<https://devfeed.tech/tags/tutorials.md>), [web](<https://devfeed.tech/tags/web.md>)

## AI overview

This tutorial explains how to build a secure e-commerce shopping cart with Firebase Authentication and Cloud Firestore. It covers guest onboarding through anonymous authentication, migration of guest carts to permanent accounts, real-time synchronization, and checkout while addressing database permissions and security.

## Source excerpt

News, tutorials, and updates from the Firebase team.