How Wix Scaled to 60M Sites: Inside Its Microservice Architecture

Background

Wix is the world’s largest DIY website‑building cloud platform, enabling anyone to create a beautiful site via drag‑and‑drop. It hosts 60 million sites in 190 countries, stores 2 PB of user files (growing 1.5 TB daily), runs on three data centers using Google Cloud and AWS, handles 15 billion HTTP requests per day, and is maintained by a 400‑person engineering team.

Architecture

Founded in 2006, Wix originally used a monolithic stack built on Java, Hibernate, Ehcache, Tomcat, and MySQL. By 2008 the monolith showed limitations, especially because the platform serves two major functions: serving published sites and supporting the site‑building editor. Changes to the editor often risked impacting the live‑site service.

To mitigate this, Wix migrated to a service‑oriented architecture, splitting the two functions into over 100 independent microservices built mainly with Scala, Jetty, and Spring. Each microservice runs as a separate stateless application with its own dedicated database, enabling frequent deployments.

The original Flash‑based editor was replaced in 2011 by an HTML5/JavaScript implementation, later adopting React. Wix’s microservices are grouped into four domains:

Wix Public : Serves published sites, using Scala, Jetty, Spring, MySQL; front‑end sites built with React + JSON.

Wix Editor : Provides the site‑building editor, developed in JavaScript, stores editor output as JSON in MySQL, and media files in the WixMP system; also Scala, Jetty, Spring, MySQL.

WixMP : Media file system handling images, videos, music, etc., integrated with CDN, running on Google Cloud and AWS, using Python/Go/C for heavy processing.

Verticals : Additional services such as e‑commerce or hotel modules, front‑end built with Angular, back‑end with Scala, Jetty, Spring, MySQL.

Wix treats MySQL as a NoSQL‑like store, using a primary‑key plus a JSON column without joins, which simplifies cross‑data‑center replication and yields sub‑millisecond lookups even on massive tables.

In 2012 Wix opened an application SDK, allowing third‑party components (e.g., blogs, CRM) via iframes, JavaScript SDK, and REST APIs.

Development Tools

Build: Maven, Grunt, TeamCity

Version control: GitHub

Project management: Jira

Deployment: Chef

Configuration: ZooKeeper

A/B testing: Petri

Monitoring: New Relic, Nagios, Graphite

BI: Hadoop, Pig, HBase, Storm

Microservices run on the JVM using Jetty, Spring MVC, and a custom framework; inter‑service communication uses JSON/RPC and ActiveMQ; storage includes MySQL and MongoDB; front‑end tooling includes Angular, React, and associated build/test tools.