Principal E-Commerce Engineer

About Happy Health Happy Health is revolutionizing sleep medicine delivery through our comprehensive telehealth platform. We've eliminated the traditional barriers to sleep care – no more waiting months for appointments or spending uncomfortable nights in sleep labs. Our patients receive FDA-cleared home sleep testing via Happy Ring, connect with board-certified sleep specialists, and when required, begin evidence-based treatment within just 5 days. Ongoing physiological data monitoring with the Happy Ring enables real-time condition management, combination therapies, and drives measurable outcomes. Happy Ring represents the future of sleep diagnostics: an FDA-cleared medical device integrating advanced biometric sensors with AI-powered analysis to deliver highly accurate diagnostics and longitudinal management at home. For sleep medicine physicians, this means you'll have access to high-quality diagnostic data that empowers you to make confident clinical decisions for your patients, and integrate multimodal treatments that focus on root-cause solutions. Overview This is a hands-on principal-level role with direct ownership of the architecture, implementation, operation, scalability, reliability, security, and long-term evolution of our customer-facing eCommerce systems, storefront infrastructure, payment workflows, attribution and analytics instrumentation, and related integrations. As part of the software team behind the Happy Health product, you will collaborate with both technical and non-technical leaders across multiple disciplines to ensure that the purchasing, subscription, fulfillment, and post-purchase experiences around Happy Health are seamless, reliable, and built to scale. You will help ensure that the integrated systems underlying the end-to-end commerce experience (including Shopify, Stripe, CRM via Customer.io, 3PL, funnel analytics via Mixpanel, and marketing attribution) are not only well designed and implemented, but also operated reliably over time to support near-term commercial growth and long-term platform needs. This role also provides technical leadership across eCommerce architecture, payment and checkout strategy, attribution and analytics infrastructure, engineering standards, and platform decision-making. Key Responsibilities Architect, build, operate, maintain, and evolve our eCommerce stack centered on Shopify and related systems to support customer-facing storefront experiences and internal operational workflows. Lead the design, implementation, and ongoing operation of integrations, services, and workflows that support the full commerce lifecycle, including product catalog, checkout, payments, subscriptions, order management, fulfillment, refunds, and post-purchase experiences. Establish and guide eCommerce engineering best practices across system design, observability, reliability, performance, maintainability, and security. Provide hands-on technical leadership to other team members, contractors, and partners building on and supporting these systems. Drive architectural decisions and cross-functional technical alignment across software, mobile, eCommerce, operations, DTC marketing, and partner-facing systems. Help ensure security, compliance, and best practices are maintained across commerce systems and payment workflows, including integrations involving customer accounts, transaction processing, and downstream operational systems. Own and help evolve the technical implementation and ongoing operation of attribution, analytics instrumentation, conversion tracking, and related data flows across the commerce funnel. Partner with DTC marketing and related stakeholders to ensure landing pages, campaign tracking, event instrumentation, and attribution inputs are implemented reliably, maintained over time, and support accurate measurement of funnel and channel performance. Monitor and improve the observability, reliability, and performance of commerce, payment, attribution, and analytics workflows in production, and proactively identify and resolve operational issues, platform gaps, and data integrity issues. Identify technical risks, scalability bottlenecks, platform gaps, and analytics or attribution reliability issues early, and proactively drive solutions that support near-term commercial growth and long-term platform needs. Required Qualifications 8+ years of software engineering experience, with meaningful depth in ecommerce systems Significant hands-on experience with Shopify, including custom storefront development, APIs, app integrations, and platform limitations Strong experience with Stripe and production-grade payment processing systems Deep understanding of ecommerce architecture, including checkout flows, order lifecycle, refunds, subscriptions, discounts, taxes, and transaction edge cases Experience implementing, maintaining, and operating analytics instrumentation, attribution systems, event tracking, or related marketing technology integrations in production eCommerce environments Strong experience designing and operating reliable, scalable production systems Experience with modern web application architecture and performance optimization for conversion-sensitive customer experiences Experience integrating ecommerce platforms with third-party systems such as ERP, OMS, WMS, CRM, analytics, support, or marketing systems Demonstrated ability to lead major technical decisions across systems, services, and teams Strong communication skills and ability to work cross-functionally with both technical and non-technical stakeholders Proven ability to operate autonomously and set technical direction while remaining hands-on Preferred Qualifications Experience with Shopify Plus Experience in high-growth direct-to-consumer or consumer health ecommerce environments Experience with subscription commerce and recurring billing models Experience with managing and simplifying diverse multi-vendor API integrations Experience with headless commerce architectures and evaluation of when they are or are not appropriate Experience with multi-store, multi-brand, or international ecommerce implementations Experience designing event-driven or asynchronous workflows for ecommerce operations Experience working in regulated, high-trust, or operationally complex environments Experience mentoring senior engineers and influencing engineering standards without direct people management responsibility Collaboration This role will work closely with software engineering, product, growth, operations, finance, customer experience, and leadership. This person will also play a key role in evaluating and managing external platform vendors, service providers, and technical integration partners as needed. Work Environment This is a senior individual contributor role for someone expected to operate with high autonomy, strong judgment, and high technical ownership. The ideal candidate is comfortable moving between architecture, implementation, debugging, and cross-functional decision-making in a fast-moving environment. Happy Health is an equal opportunity employer. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.