Principal Design System Architect

Microsoft•Redmond, WA

About The Position

The Fluent Design System team is redefining Microsoft 365’s design system for the AI era. As M365 Copilot evolves into a rich, multimodal productivity platform, Fluent is transforming from traditional design systems into an adaptive, model-aware design foundations—one that blends GUI precision with generative, context-aware behaviors at scale. As a Principal Design System Architect, you'll help shape the future of how AI-native experiences are designed, built, and sustained at an ecosystem-level. This role sits at the intersection of design, engineering, and emerging AI systems, with direct influence over the patterns, primitives, and architectural decisions that power M365 Copilot and the broader Microsoft ecosystem. You’ll work within X3, a global, multidisciplinary organization dedicated to bringing humanity, clarity, and trust to AI-powered experiences. Fluent is a critical layer in that mission—providing the shared language, systems thinking, and technical rigor needed to ensure quality, coherence, and craft as AI reshapes productivity software. What You’ll Do As a senior individual contributor, you’ll operate both strategically and hands-on—driving foundational decisions while actively prototyping and exploring what’s next. Architect AI-Native Design Systems: Define and evolve the core design system architecture that supports generative UI, adaptive layouts, multimodal input/output, and model-driven behaviors—ensuring Fluent scales across platforms, products, and future Copilot experiences. Bridge Design and Systems Thinking: Partner deeply with engineering, PM, and research to influence how backend services, LLM capabilities, and system constraints shape front-end design patterns. You’ll help translate AI capabilities into usable, reliable, and human-centered design primitives. Design Like a Maker: Prototype early and often—using code, design tools, and AI workflows to test ideas, explore new interaction models, and pressure-test system assumptions. You’re comfortable working across prompts, components, tokens, and abstractions to move ideas forward. Set Long-Term Direction: Identify the design system decisions that matter most over a 6–12 month horizon. You’ll help Fluent stay ahead of delivery by researching, experimenting, and defining future-facing patterns while the broader team focuses on execution. Scale Through Influence: Raise the technical and systems fluency of designers across Microsoft by coaching, documenting frameworks, and shaping shared mental models. Your impact is felt not just through what you build, but through how others build with Fluent. Champion Craft, Quality, and Coherence: Advocate for clarity, accessibility, performance, and design excellence in a rapidly evolving AI landscape—ensuring that innovation never comes at the cost of trust or usability. Why This Role Matters Fluent is more than a visual system—it’s the connective tissue for how we work together. It's what allows Microsoft 365 to move fast without fragmenting. In this role, you’ll help ensure that as AI accelerates what’s possible, the experience remains cohesive, intuitive, and deeply human. If you’re excited by re-architecting design systems for an AI-first world, influencing how models and interfaces work together, and building foundations that millions rely on every day, this team may be the right place for you. Microsoft’s mission is to empower every person and every organization on the planet to achieve more. We work with a growth mindset, lead with empathy, and build inclusive systems that help people thrive—at work and beyond.

Requirements

Master's Degree in Industrial Design, Product Design, Human Computer Interaction, User Experience, Interaction Design, or related field AND 6+ years experience working in product or service design
OR Bachelor's Degree in Industrial Design, Product Design, Human Computer Interaction, User Experience, Interaction Design, or related field AND 8+ years experience working in product or service design
OR equivalent experience.

Responsibilities

Explore and apply emerging AI tools (LLMs, prompting workflows, generation pipelines, evaluation loops) as part of the default design-system workflow.
Prototype and build practical utilities that accelerate concept → shippable system artifacts (components, tokens, documentation, integration workflows).
Define how AI models interface with Fluent libraries and foundations.
Define system architecture and scalable foundations across tokens, components, documentation, and usage patterns.
Establish lifecycle standards for design system assets.
Create durable “ways of working” that keep design intent aligned with implementation.
Translate product experimentation into reusable system primitives.
Partner with Engineering and PM to define long-term design-system strategy and sequencing.
Drive clarity around architectural decisions, governance, and adoption models.
Make hard-to-undo decisions visible, testable, and scalable.
Lead cross-discipline reviews and workshops to align designers and engineers around system-level decisions.
Raise the overall craft and technical fluency of the organization.