Senior Design Engineer - AssemblyAI

Why AssemblyAI

AssemblyAI builds the best-in-class Voice AI models powering the next generation of voice applications. Our models serve 600M+ inference calls monthly, process 1M+ hours of audio daily, and power 2 billion+ end-user experiences. The Voice AI space is at an inflection point; we're looking for folks truly excited to join a small team and help define the future of the industry.

We are one of the most capital-efficient AI companies on the planet—with under 100 people generating roughly $500K ARR per employee, we sit among the top 5 most revenue-dense teams within the fastest-growing AI companies today. With thousands of customers including Granola, Fireflies, Figure AI, and CallRail, the company has real scale.

About the role

We're looking for a Senior Design Engineer to own the craft and feel of AssemblyAI's product experience end to end. This person will design and build the interfaces our developers live in, from the Playground to the dashboard, and hold the bar on how everything looks, moves, and feels, not just whether it works. You lead with design, using engineering to bring that vision to life without needing to hand it off.

What You’ll Do

• Own the visual and interaction design of our core product surfaces, then build them in production React and TypeScript.
• Set the bar for UX quality across the product: interaction states, motion, hierarchy, and fine details.
• Take rough product ideas and turn them into polished, high-fidelity experiences, prototyping quickly to pressure-test direction.
• Shape and steward our design system and visual language so quality scales as the product grows.
• Partner directly with engineering and marketing on direction, not just execution.
• Use AI tooling and agents as a core part of your workflow to design and ship faster.

What You’ll Need

• A strong portfolio of shipped product work demonstrating real design taste and craft.
• Genuine UX and visual design ability, from concept through high-fidelity execution.
• Deep proficiency in Figma, comfortable moving from low-fidelity exploration to high-fidelity, dev-ready designs and maintaining shared component libraries.
• Solid frontend engineering skills, comfortable building production interfaces in modern React and TypeScript.
• Fluency with AI-assisted design and development, and an instinct for building AI-native interfaces.
• Comfort operating with ambiguity and owning outcomes end to end.

Nice To Have

• Motion design chops, comfortable using animation and micro-interactions to make an interface feel alive.
• Illustration or visual storytelling ability to create original graphics, diagrams, or brand-aligned artwork.
• Experience designing for developer platforms or API-first products.