Principal Engineer, ML

Principal Engineer, Ads Serving & ML Platform

We exist to wow our customers. We know we’re doing the right thing when we hear our

customers say, “How did we ever live without Coupang?” Born out of an obsession to make shopping, eating, and living easier than ever, we’re collectively disrupting the multi-billion- dollar e-commerce industry from the ground up. We are one of the fastest-growing e-commerce companies that established an unparalleled reputation for being a dominant and reliable force in South Korean commerce.

We are proud to have the best of both worlds — a startup culture with the resources of a large global public company. This fuels us to continue our growth and launch new services at the speed we have been since our inception. We are all entrepreneurial surrounded by opportunities to drive new initiatives and innovations. At our core, we are bold and ambitious people that like to get our hands dirty and make a hands-on impact.

At Coupang, you will see yourself, your colleagues, your team, and the company grow every day

Our mission to build the future of commerce is real. We push the boundaries of what’s possible to solve problems and break traditional tradeoffs. Join Coupang now to create an epic experience in this always-on, high-tech, and hyper-connected world.

About the Role

Coupang is seeking a Principal Engineer to define and lead the technical vision for our Ads Serving & ML Platform, one of the company's most critical business systems powered by large-scale machine learning and AI. Advertising plays a vital role in Coupang's ecosystem, enabling customers to discover relevant products while helping advertisers grow their businesses. The Ads platform directly influences customer engagement, advertiser success, and long-term revenue growth at massive scale.

As a Principal Engineer, you will own the architecture and technical strategy of the end-to-end ads serving ecosystem, spanning retrieval, ranking, auction, targeting, machine learning infrastructure, and online serving systems. You will identify future technology investments, drive innovation across organizational boundaries, and ensure that our platform continues to scale in performance, reliability, intelligence, and efficiency.

This is a highly influential individual contributor role requiring exceptional technical depth, strategic thinking, and cross-functional leadership. You will partner with engineering, machine learning, product, and business leaders to solve some of the most challenging problems in large-scale distributed systems and AI-powered advertising.

What You Will Do

Define and drive the long-term technical vision, architecture, and strategy for Coupang's Ads Serving & ML Platform.

Lead the design and evolution of large-scale ad serving systems, including retrieval, ranking, auction, targeting, pacing, and measurement.

Drive platform modernization and adoption of emerging technologies, including large language models, generative AI, real-time inference, and next-generation ML infrastructure.

Identify and lead strategic technical investments that improve advertiser outcomes, customer experience, system scalability, and operational efficiency.

Partner with engineering, machine learning, product, and business leaders to align technical direction with company priorities and business objectives.

Influence architecture and engineering excellence across multiple organizations through technical leadership, design reviews, and mentorship.

Establish best practices for platform reliability, performance, scalability, observability, and operational excellence.

Drive measurable business impact through innovations that improve engagement, conversion, relevance, advertiser ROI, revenue growth, system efficiency and cost.

Serve as a recognized technical leader and domain expert in large-scale advertising systems and machine learning platforms.

Required Qualifications

12+ years of experience building large-scale so