Principal designer, UX expert, and software engineer with 20+ years of experience delivering enterprise-scale solutions. Bridges technical and design teams to execute platform integrations, migrations, design, and complex system analysis and optimization. Trusted by Fortune 500 and global clients for strategic problem-solving, stakeholder engagement, and high-impact results.
20+
Years of experience
20+
Enterprise companies
Fortune 500
Clients served
2025
Zeroheight award
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Led UX across multiple AWS initiatives and Amazon Business, designing complex internal platforms including localization tooling managing global translation workflows, campaign management systems tracking hundreds of millions in budget, and the Business registration flow serving global enterprise teams at massive scale. Reduced user onboarding time by 30%.
Principal Designer and Software Engineer with 20+ years of experience delivering enterprise-scale platforms, systems, and digital products. I operate at the intersection of UX, engineering, and business, bridging design and development to drive clarity, alignment, and execution across complex, high-impact environments.
I have led and delivered work across organizations including Amazon Web Services, Boeing, T-Mobile, and the Department of Defense, often acting as the connective layer between teams or owning delivery end to end. My work includes defining and creating product requirements, platform integrations, large-scale migrations, system architecture, design system evolution and governance, complex system analysis, and building production applications from the ground up.
My strength is turning complex ideas into clear, structured, and actionable requirements, then carrying them through design and implementation into scalable, production-ready solutions. I define information architecture, shape product direction, design user experiences, establish system patterns, and contribute across implementation where needed. I work directly with product, engineering, and business stakeholders to align priorities, reduce ambiguity, and deliver outcomes that hold up in real-world use.
I am most effective on projects that require both strategic thinking and hands-on execution, especially where systems are complex, requirements are evolving, or teams need a clear path forward.
Selected achievements
Led UX across multiple AWS and Amazon Business initiatives, designing internal platforms including localization tooling for global translation workflows, campaign management systems tracking hundreds of millions in budget, and the Business registration flow for enterprise teams.
Designed the foundational UX logic for T-Mobile ScamShield, the platform logic behind it, and multi-channel eCommerce campaigns including T-Mobile Tuesdays with Nike, Shell, and Fitbit. When the platform migrated to T-Life, the ScamShield work migrated with it and remains in use today serving over 10 million customers.
Audited and evolved an enterprise design system across a React-Native codebase, Zeroheight, and Storybook, guiding engineering and mentoring a team of designers throughout. As the only designer approved to contribute directly to the React-Native codebase, the design system won the 2025 People's Choice Award at the Design System Awards, presented by Zeroheight.
Led the integration and build for a suite of 6 enterprise applications for a major enterprise client, delivered on time and under budget. Served as the sole designer and requirements lead across the engagement, working directly with product and engineering to drive delivery. Recognized at the Slalom Team Summit for the outcome.
Built a responsive React application for real-time executive decision-making as the sole front-end developer. Contributed backend code where needed to maintain the delivery schedule. Facilitated multi-day design sprints with VPs, engineers, and mechanics across locations.
Designed and built two AI platforms for a major enterprise web services company as the sole designer and front-end developer, working alongside a team of backend engineers. Also built production front-end applications in React and Angular across multiple enterprise clients.
Established a new type of engagement at Slalom with a major enterprise web services client in 2024, which grew to staff multiple consultants over time.
At Mouseflow, I created a Website Consultation Service from scratch that produced a 91% increase in direct sales revenue in six months and 150% subscription growth in the first month.
"She has that rare ability to merge artistic vision with technical excellence, allowing her to excel as a designer, developer, and project manager. Whether she was crafting compelling graphics and campaigns, building seamless user flows, or writing clean, efficient code, Stefanni consistently elevated the quality of every project she touched."
People Leader and Direct Manager, Slalom Consulting
"Stefanni's rare ability to bridge design strategy and software implementation sets her apart. She led a team to deliver a scalable UI solution that reduced user onboarding time by 30%. Her design intuition and technical expertise enable her to transform complex ideas into high-value solutions, consistently delivering under tight timelines in fast-paced environments."
Director of Software Engineering, Slalom Consulting
"Projects that should have failed did not, and projects destined to succeed were considered hallmarks. She's driven, intellectual, and professional, all while being relatable, uplifting, and an asset to every project she's been a part of. Simply put: she is a force multiplier."
Senior Consultant and Software Engineer, Slalom Consulting
"She brings a thoughtful, supportive approach that makes it easy for others to learn, grow, and contribute. Stefanni has a unique ability to break down complex concepts into clear, visual explanations. Her diagrams and walkthroughs made even the most technical features easy to understand, and she naturally creates space for questions while welcoming different perspectives."
Senior Consultant, Slalom Consulting
Principal Designer & Software Engineer
