Staff Machine Learning Engineer (Ads Relevance)

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. Role Overview Coupang Ads is responsible for providing vendors that sell their products on Coupang with a host of marketing products and services. We launched the Product Ads performance advertising marketplace in late 2018. We have grown rapidly into a multi-billion USD ads business over the past few years, and we continue to grow fast. Our org is responsible for advertising brands and products on our e-commerce platform, a crucial aspect of our business that rivals the success seen by giants like Alibaba and Amazon. The Ads Relevance team, a key part of the Ads organization, is at the forefront of developing cutting-edge AI/ML models to deliver contextually relevant advertisements to Coupang's customers. Rather than chasing "the best" in a vacuum, our team pursues optimal and practical engineering. To achieve the highest possible relevance quality within given resources, we foster a collaborative environment where we study the latest literature, engage in deep discussions, and conduct diverse experiments together. Our tech stack for achieving optimal relevance is broad and sophisticated, spanning the latest Large and Small Language Models (LLMs), two-tower embedding models (TTMs), and DNN models. We are constantly striving for technical excellence across these domains to push the boundaries of what's possible. At Ads Relevance, we thrive on data-driven decision-making and experimentation. In an era of rapid AI evolution and the emergence of next-gen tools like coding agents, we embrace new challenges with agility. We foster a culture of horizontal collaboration and open idea-sharing to stay ahead in this fast-paced landscape. We are looking for passionate individuals who are eager to create better ad experiences and contribute to our innovative team. Qualifications Over 5 years of industry experience in software engineering, specializing in machine learning, language modeling, recommendation systems, and information retrieval. Strong problem-solving skills through scientific approaches such as observation, hypothesis, experimentation, evaluation, and analysis. Ability to quickly keep up with the latest research trends and apply them to production. Ability to accelerate AI model development lifecycles by leveraging coding agents such as Claude Code and Devin. Proficient in writing logical and technical documentation. Ability to work effectively in multicultural, cross-functional teams. Bachelor's degree in computer science, engineering, mathematics, physics, science, or equivalent. Preferred Qualifications Industry Experience in the advertising, recommendation systems, or search engine domains. Master's or Ph.D. degree in computer science, engineering, mathematics, physics, science, or equivalent.