Senior Staff Backend Engineer - Billing

Coupang is reimagining the shopping experience with the goal of wowing each customer from the instant they open the Coupang app to the moment an order is delivered to their door. Powered by an outstanding end-to-end e-commerce and logistics network and a fanatical culture of customer centricity, Coupang has broken tradeoffs around speed, selection and price. Today, we provide exceedingly fast shipping speeds on millions of items including fresh groceries, delivered within hours nationwide, 365 days a year. We are doing this for millions of consumers in Korea. Korea is home to one of the largest and fastest growing e-commerce opportunities anywhere in the world. 

Coupang has been added into the 2023 fortune 500 list, a ranking U.S-based companies by revenue. We have been named as one of the ‘50 Smartest Companies in the World’ by MIT Technology Review, and as one of Forbes magazine’s ‘30 Global Game Changers.’ In 2020, we placed second on CNBC’s ‘Disruptor 50’ list.  

Job Overview:

The Billing and Usage - Software Engineering team is responsible for customer account management as well as the usage and billing for customers.   

We are looking for a Senior Staff Software Engineer, who will serve as a technical strategist and domain leader for our end-to-end cloud metering and billing infrastructure.  You’ll architect horizontal platforms that handle usage ingestion, billing computation, invoice generation, and customer entitlements at hyperscale.  You will be expected to define the technical vision and influence the broader engineering direction for how cloud products are priced, tracked, billed, and paid — impacting every customer from startups to enterprises.

What You Will Do

As a Senior Staff Software Engineer, you will partner with leaders of multiple platform teams to define long-term architecture vision for global billing systems, catalog services, and pricing engines. You will provide architectural guidance for building highly available, financially compliant, and auditable systems and partner with product team to define the roadmap for real-time metering pipelines, cost transparency APIs, and usage attribution models.  You will coach senior engineers across teams and develop strong technical ICs and advocate for engineering rigor, reusable abstractions, and shared service boundaries.

In this role, you will:

• Lead the design of scalable, event-driven microservices for metering, pricing, billing, and invoicing.
• Own the architecture of account hierarchy, subscription, and billing relationships (organization, teams, projects).
• Hands-on develop critical infrastructure components. 
• Decompose complex problems into simple, straightforward solutions, providing mechanisms for the teams to prioritize ruthlessly and “move with urgency”.
• Envision roadmaps for the scalable and robust growth of billing infrastructure.
• Collaborate with Product owner, TPMs, FinOps, and Compliance teams to define end-to-end billing experiences. Proactively drive billing initiatives and align with stakeholders.
• Demonstrate excellence resulting in scalable systems and services with the highest quality architecture and design.
• Dive deep into critical system issues, proactively addressing similar root causes, and raise the bar on Operational Excellence.
• Collaborate with other Coupang tech leaders to make the service extensible to unlock opportunities for innovations.

Qualifications

• 13+ years professional software development experience
• Track record of building multi-tenant, financial-grade cloud infrastructure at scale.
• Expertise in stream processing, distributed stateful services, immutable data models, and financial correctness.
• Strong communication skills with ability to influence org-wide technical decisions.
• Hands-on experience in designing and developing large scale distributed system in the last 4 years. 
• One who is fluent in one or more among Java, Go and Python.
• Proven track record of delivering mission critical systems.
• Experience developing and growing senior individual contributors globally.
• Experience with cloud computing using AWS or Azure or GCP.
• Experienced in Machine learning job deployment infrastructure like Ardo CD workflow.

   
Preferred Qualifications 

• Deep domain knowledge in cloud billing, dynamic pricing, rate card versioning, invoice rules, and quote-to-cash flows.
• Exposure to cross-functional work with FinOps, Revenue Ops, and Compliance.
• Contributions to usage analytics, predictive billing, or ML-based cost attribution systems.
• Experience in Kubernetes, gRPC. 
• Experience in concurrency, multi-threading, synchronization, and non-blocking IO. 
• Deep understing of operating system kernel and distributed system such as Kafka, Cassandra and Mongo DB.
• Proficient in some of the ML infrastructure and deployment frameworks like: TensorFlow, PyTorch, TensorRT, Triton backend etc.
• Ability to handle multiple competing priorities in a fast-paced environment and leading the delivery of large-scale services for complex business offerings.
• Ability to influence cross functional stakeholders, prioritize ruthlessly, Aim High and Find a Way to deliver results with grit.