Java backend and full-stack engineers. A marketplace lists millions of items, takes orders around the clock and keeps search, cart and checkout fast under heavy load. Java engineers build these services, most of all at eBay, and at the home-goods marketplace Wayfair, the direct-to-consumer brand Quince and the Indian marketplaces, like Flipkart and Meesho. They are the most common opening, well above their usual weight. The postings require Spring Boot with Kafka and Elasticsearch, and many also require React, Python or Node.

Mobile engineers. Most shopping happens in an app. Mobile engineers build the shopping, resale and service apps, in Swift and SwiftUI for iOS and Kotlin for Android, with GraphQL. They are several times as common here as at a typical product company, at eBay, the resale apps, like StockX and Poshmark, and the brands, and the brands take juniors into these roles readily.

Data engineers. Every search, click and order feeds data that decides what to show, what to stock and what to charge. Data engineers build those pipelines in Python and Java with Spark, Kafka, Flink and Scala, mostly at eBay and Wayfair. They are more than twice as common here as elsewhere.

Cloud and DevOps engineers. A marketplace cannot go down during a sale. Cloud engineers run these platforms in Python, Java and Go with Kubernetes and Terraform, mostly at eBay, and they hold about their usual place.

ML engineers. Search ranking and recommendations decide what a shopper sees first. eBay hires most of the ML engineers here, who train these models in Python with PyTorch, Spark and TensorFlow. They are about three times as common here as at a typical product company.

Generalist software engineers in E-commerce and D2C brands. Several marketplaces and brands, like eBay and Fanatics, hire under a plain software engineer title, for ordinary backend and full-stack work in Python, Java and TypeScript.

Test engineers. Testers are less common here than at most product companies, mostly at the resale apps. Many of the postings are for testing mobile apps with Appium, alongside Selenium and Playwright.

Go engineers. The Southeast Asian super-app Grab, the resale apps and the home-services apps Snabbit and Urban Company hire Go engineers for their services, and this role takes juniors readily.

JavaScript and Node engineers. eBay and Pattern, a company that runs brands' stores on other marketplaces, hire Node engineers with React, TypeScript and GraphQL.

Also present. A small group of fintech software engineers working on payments at eBay and Grab, frontend engineers, Software Engineer, Security roles working on sign-in and identity at eBay, .NET engineers at the electronics distributor Mouser Electronics and the product-content company Syndigo, platform and integration developers, and a small group of GenAI engineers, far below their usual weight.

Rare here. SAP, firmware and C/C++ work barely appear.