Senior Staff Backend Security Engineer

Coupang•Mountain View, CA

About The Position

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 entrepreneurs 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 We are seeking a highly skilled Senior Staff Backend Security Engineer with deep technical expertise and a passion for building secure, reliable, and scalable systems. This role focuses on technical leadership, architecture, and hands-on development to ensure the security and resilience of our core platforms. You will drive the security, quality, and reliability of backend systems while influencing architecture decisions, mentoring engineers, and partnering with product teams on strategic initiatives.

Requirements

Bachelor's degree in Computer Science or related technical field.
8 years of professional software development and security engineering experience.
Proven experience designing and developing large-scale distributed systems.
Strong knowledge of security architecture

Nice To Haves

Recent hands-on experience (last 3-4 years) building secure, distributed systems at scale, with strong exposure to AI/ML development and hosting in production environments.
Experience with cloud platforms (AWS, Azure, GCP) for identity, ML infrastructure, and secure deployment.
Familiarity with Generative AI integration and responsible implementation of LLM-based workflows.
Exposure to data security principles, including encryption, secure data pipelines, and compliance frameworks.
Ability to influence technical direction and mentor engineers in security best practices.
Proven track record of delivering mission-critical, scalable systems in production at enterprise scale.
Expertise in Java, Spring Boot, and AWS architecture/services (EKS, S3, Lambda, RDS, IAM, KMS).
7+ years of solid experience with fundamental algorithms, system design, and large distributed systems.
Deep experience in cryptography and PKI systems, including certificate management and secure key lifecycle
7+ years of coding experience, specifically in Java.
Strong knowledge of security architecture, authentication/authorization, and cryptographic principles.
Hands-on experience in building large-scale serving and data infrastructure.
Experience with service-oriented architecture and web application/services development
Practical experience in utilizing AWS (Amazon Web Services).
Experience in designing and constructing machine learning-based applications and systems.
Experience in leading cross-team system design and execution.

Responsibilities

Architect and implement secure, scalable backend systems using Java (Spring Boot) and AWS cloud-native services.
Lead technical design reviews, enforce security best practices, and ensure system reliability and performance.
Develop and integrate security features such as authentication, authorization, and identity management (SSO, OIDC, RBAC/ABAC, SCIM).
Design and implement API security patterns and API authorization at scale for microservices and service mesh environments.
Embed Generative AI capabilities (e.g., embeddings, RAG, LLM APIs) into product workflows securely and responsibly.
Write and review code, unblock complex technical challenges, and make critical architectural decisions.
Champion secure SDLC practices, cryptography standards, and compliance requirements.
Collaborate with cross-functional teams to define technical roadmaps and deliver mission-critical systems at scale.