Principal Software Development Engineer

At Expedia Group, we help travelers explore the world, one journey at a time. As a global travel company powered by passionate people, trusted partnerships, and leading technology, we connect travelers, partners, and advertisers through our consumer brands, B2B network, and travel advertising business.

Here, you'll do meaningful work that helps millions of people discover, book, and experience travel with more ease, confidence, and joy. Our five Behaviors-Traveler First, Think Big, Operate with Excellence, Ownership Mindset, and Succeed Together-help foster a supportive environment where people can grow their careers and have the flexibility, benefits, and support to do their best work. Join us and build for travelers everywhere.

Introduction to the Team:

Our Technology Team partners with teams across Expedia Group to create innovative products, services, and tools to deliver high-quality experiences for travelers, partners, and our employees. A singular technology platform powered by data and machine learning provides secure, differentiated, and personalized experiences that drive loyalty and traveler satisfaction.     

At Expedia Group Fraud & Risk (EFR), we are the guardians of marketplace trust. We protect EG from financial loss and brand damage, securing every channel for our customers, partners, suppliers, and employees. Our world class engineering and machine learning turn massive, noisy signals into real time decisions that minimize risk while keeping traveler friction low.

What makes this work unique: in travel, risk doesn’t stop at checkout, it spans the entire journey. The global ecosystem is vast and fragmented, control points are scarce, and every leg introduces new unknowns. Our mission is bold: deliver a fully trusted journey from purchase to safe return home. That’s hard and exactly why science and technology matter most.

If you’re energized by complex, high impact problems with no obvious answers, and want to shape the future of risk with AI on a global scale, join us. Let’s redefine how the world travels, safely, confidently, and at speed.

Lead the architecture and delivery of real-time, AI-powered fraud and abuse defenses on a global scale. You will design cloud-native decisioning and automated remediation systems, simplify our platform, and align cross-functional teams to measurable outcomes.

In this role, you will:

• Own end-to-end architecture for low-latency risk decisioning (signals + rules + models) and automated remediation

• Build, deploy, and operate ML in production; partner closely with DS/ML on features, experimentation, and monitoring

• Simplify and modernize the platform (streaming/data pipelines, microservices, CI/CD, configuration-driven controls) to speed safe iteration

• Drive build-vs-buy evaluations and benchmark vendors against in-house solutions for performance, cost, and risk posture

• Establish clear SLOs, observability, and safety/rollback mechanisms; ensure security, privacy, and compliance are built in

• Mentor senior engineers and align Product, Ops, Security, and Compliance on roadmap and outcomes

• Communicate clearly with executives and engineering: distill strategy, make tradeoffs explicit, and document decisions.

Minimum Qualifications:

• 10+ years of software engineering, including 4+ years leading architecture for real-time, high-scale systems

• Proven experience building and operating fraud/risk systems in production (e.g., booking, payments/chargebacks, ATO, content/supplier integrity), with measurable impact on losses, false positives, and manual effort

• Production ML experience (supervised/anomaly detection, feature pipelines, online inference, monitoring/retraining); ability to ship with DS/ML partners

• Cloud-native engineering at scale (AWS, GCP, or Azure): event-driven services, data/stream processing, observability, cost and reliability best practices

• Strong coding skills in one or more of Java/Scala/Go/Python; microservices, APIs, and infrastructure-as-code

• Security, privacy, and regulatory fundamentals for sensitive data and risk decisioning

• Experience with executive communication: can brief executives, translate strategy into actionable engineering plans, and align teams

Preferred Qualifications:

• LLM/agentic techniques applied to fraud (e.g., investigation assist, pattern discovery, automated playbooks) and retrieval over enterprise data

• Graph/sequence modeling or entity resolution at scale; device and behavioral signals

• Track record reducing manual operations via automation and platform simplification

• Hands-on with experimentation platforms and real-time rules/model simulation/back testing

• Deep cloud cost/performance tuning and capacity planning

• Marketplace, travel, or e-commerce experience

The total cash range for this position in Seattle is $231,000.00 to $323,500.00. Employees in this role have the potential to increase their pay up to $369,500.00, which is the top of the range, based on ongoing, demonstrated, and sustained performance in the role.

Starting pay for this role will vary based on multiple factors, including location, available budget, and an individual’s knowledge, skills, and experience. Pay ranges may be modified in the future.

Benefits and perks

Expedia Group offers benefits and perks designed to support employees and their families, including medical, dental, and vision coverage, paid time off, an Employee Assistance Program, wellness and travel reimbursement, travel discounts, and International Airlines Travel Agent Network (IATAN) membership. Learn more about life at Expedia Group at .

Accommodation requests

Expedia Group is committed to providing an inclusive and accessible recruiting experience. If you need an accommodation or adjustment due to a disability during the application or recruiting process, please submit a request at .

About Expedia Group

Expedia Group includes three flagship consumer brands - Expedia, Hotels.com, and Vrbo - along with a leading B2B travel business and travel advertising offerings. Across our brands and business, we help travelers explore the world with confidence and ease.

Important notice

Employment opportunities and job offers at Expedia Group will always come from Expedia Group's Talent Acquisition and hiring teams. Never share sensitive personal information unless you are confident of the recipient. Expedia Group does not extend job offers via email or messaging tools to individuals with whom we have not made prior contact. Our email domain is @expediagroup.com. The official place to find and apply for roles is .

Equal Opportunity

Expedia is committed to creating an inclusive work environment with a diverse workforce. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, veteran status, or any other characteristic protected by law. This employer participates in E-Verify. The employer will provide the Social Security Administration (SSA) and, if necessary, the Department of Homeland Security (DHS) with information from each new employee's I-9 to confirm work authorization.