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Managing Principal
Principal, Product and Strategy
PRINCIPAL Engineer
Managing Principal
Stefan Haney is a business and technology leader with over two decades of experience in e-commerce, software development, and supply chain. As a 15-year veteran of Amazon, with over 9 years at Accenture and internet startups, his experience includes building product, data, and engineering teams worldwide to drive innovation and business growth. Stefan is named in multiple patents for algorithms and processes built at Amazon.com after he joined in 2003. During his time at Amazon, his contributions scaled supply chain purchasing automation, drove massive growth of the Amazon Seller Marketplace business, and led the personalization of product display and purchase features in the Customer shopping experience worldwide.
Product Innovation across the Globe
Under his direction, Stefan’s teams launched dozens of customer-facing products including Seller Pricing tools, Selling Coach recommendations, and Seller Central small business management tools. Most recently, his teams integrated data science into e-commerce shopping features on Amazon product pages and drove shopping expansions into Saudi Arabia, UAE, India, Turkey, Brazil, and Australia. Stefan’s organization included Product Management, Software Engineering, Data Science, and Operations distributed across multiple locations worldwide.
As one of a few company-wide Customer Experience Bar Raisers, Stefan reviewed hundreds of proposed initiatives across the company against the Amazon Flywheel. In addition, he taught the Amazon writing and innovation processes in quarterly group trainings and one-on-one mentoring. He lived these processes as a contributor or owner of dozens of documents to Amazon senior leaders resulting in the launches of new Amazon business such as Amazon Seller Lending, Amazon B2B marketplace, and Amazon Handmade.
Stefan’s business ownership also included responsibilities for growing the Used products business on Amazon. During this period of ownership, Stefan launched a certified refurbished product program achieving over $1B of annual revenue in the first 12 months.
Technology Operations
Beyond product management, Stefan built and led the worldwide operations and availability for Amazon product shopping pages through high-traffic events such as Prime Day along with test, release, and performance optimization for thousands of releases in a distributed services environment. His teams continually pursued and set new standards in software performance optimization, latency, automation, and data security.
Hiring and Organizational Development
During his time at Amazon, Stefan conducted over 1300 phone and in-person behavioral interviews contributing to the employee growth of the Marketplace organization with 100s of new hires. He served as an Amazon Bar Raiser and trained others on Amazon hiring practices and team development during rapid organizational growth.
Amazon positions
Between December 2016 to August 2019, Stefan held the title of Director – Consumer Shopping Experience. Previously, Stefan held the position of Director – Seller Strategy and WW Sales Technology, while working at Amazon.com, Inc.. Stefan held this role for 21 months (March 2015 – December 2016). Before this, Stefan held the position of Director – Seller Experience, while working at Amazon.com, Inc.. Stefan occupied this position for 4 years (December 2010 – March 2015). Previously, Stefan held the position of Senior Manager Global Seller Tools, while working at Amazon.com, Inc.. Stefan held this role for 17 months (March 2009 – August 2010). Before this, Stefan held the position of Global Buying Systems Manager, while working at Amazon.com, Inc.. Stefan occupied this position for 5 years (November 2003 – March 2009).
Education and Additional Interests
Contact Stefan
[email protected] | 773-398-5344 | LinkedIn
Principal, product and Strategy
Greg Niejadlik is a UX strategist and product design leader with over two decades of experience in product design, bringing focus to chaos. His work encompasses engaging physical products, enterprise eCommerce, B2B SaaS, operational service maps, and marketplace ecosystems. His expertise includes UX audits, data-driven product discovery, and large-scale platform transformations. At Amazon, he spearheaded design initiatives that enhanced seller onboarding, created unique marketplace-only categories, defined the launch of Amazon Business, and developed the first global marketplace tax system. He has since provided consulting services for startups and Fortune 500 companies, concentrating on conversion optimization, international expansion, and AI-assisted product listing strategies.
At Vantage, Greg collaborates with businesses to align customer experience strategies with business growth. He conducts comprehensive UX audits, refines product architecture, and defines experiences to maximize engagement, retention, and operational efficiency. His data-driven approach ensures companies can unlock new insights and opportunities for a seamless user experience.
Greg holds degrees in Communication Design and Human-Computer Interaction from Carnegie Mellon University. He spends time with family in the Pacific Northwest, volunteers with ski patrol, and enjoys the game of baseball.
Principal Front-End Engineer
Calvin is a Principal Front-End Engineer and engineering leader who enjoys building websites and web applications. Calvin has built websites professionally since 2008 and mobile-optimized sites since 2011. He leverages a variety of technologies including JavaScript, TypeScript, Node.js, React.js, and CSS – with cloud and serverless technologies – to build and deliver world-class user experiences for e-commerce applications, B2B portals, dashboards, and internal tooling.
Over the past decade, Calvin spent 9 years at Amazon building high-performance websites including the Amazon UI framework (used by Amazon.com and the Amazon app), the Amazon product detail page, and Amazon’s Seller Central marketplace website (B2B portal). Since leaving Amazon, Calvin has worked on projects for companies including Microsoft, eMag, and Lightcast (formerly Emsi).
During Calvin’s time at Amazon, he became one of the best-known faces in the web development community through his work on the Amazon UI framework, his front-end engineering leadership in Amazon’s retail and marketplace organizations, and through his drive to create the Front-End Engineer role. As a hiring Bar Raiser, he set the standard for how to interview front-end engineers. Calvin presented about technical and career topics at 10 internal Amazon WebDevCon conferences.
Calvin holds a Bachelors in International Studies from the University of Nebraska. He and his wife enjoy small-town living in the Pacific Northwest.
