Humanloop enables product teams to build robust agents and AI features with LLMs, using best-in-class tooling for Evaluation, Prompt Management, and Observability.

You'll get the chance to work really hard on a problem that matters alongside super-smart people. The environment is fast-paced with new features being shipped every week. The customers we get to work with are themselves inspiring AI startups and forward-thinking enterprises who are also trying to use this amazing new technology to build magical products and AI experiences.

Our principles:

• Humanity first – autonomy, not automation
• Creativity that ships
• Growth mindset – iterate and improve
• Jump into the cold water
• Humility + idea meritocracy

Learn more about us in this Youtube video How our AI Startup Grew 60x After a Pivot | Raza Habib, Jordan Burgess of Humanloop

As a Design Engineer, you'll bridge the gap between engineering and design—owning the craft of building elegant, high-performance UI and design systems that scale. You'll work across our TypeScript/React frontend and collaborate closely with product and backend engineers to shape the future of how AI teams build products.

We’re a small, smart, and hardworking team operating at the frontier of AI. Our customers demand world-class performance, reliability, and usability, and we aim to set the standard for intuitive design that enables product leaders and non-technical subject matter experts to collaborate effectively with developers.

About the role

You’ll be responsible for:

• Designing and building high-quality, reusable UI components and design systems that scale.
• Crafting seamless, beautiful user experiences that make complex AI workflows intuitive.
• Bringing designs to life with polished, accessible, and performant front-end code.
• Making strong calls on when to build in-house solutions versus leveraging existing tools.
• Owning the end-to-end implementation of features that balance usability, aesthetics, and engineering efficiency.
• Advocating for best practices in design, accessibility, and front-end architecture.
• Engaging with users to understand their needs, ensuring the product is both functional and delightful.

About you

• You have a deep appreciation for great design and care about the finer details of UI/UX.
• You are equally comfortable designing interfaces and implementing them in code.
• You understand systems thinking and have experience building scalable design systems.
• You are capable in Figma
• You have strong frontend engineering skills in TypeScript, React, and TailwindCSS (or equivalent modern stacks).
• You are excited by AI and its potential, and want to shape the way teams interact with it.
• You hold yourself and others to a high bar, striving for elegance and simplicity in design and code.
• You thrive in a fast-moving startup environment and want to have real impact.
• You communicate clearly, collaborate well, and enjoy engaging with users to improve the product.

Our stack

We aim for a modern, pragmatic stack that optimizes for speed and developer happiness:

• Frontend: TypeScript, React, Next.js, TailwindCSS, Radix UI
• Backend: FastAPI (Python), Postgres
• Infrastructure: AWS

Offices in London and San Francisco

This role is primarily for San Francisco.

If London is a more suitable location for you that can be arranged. We work in our HQ in SoMa, with flexibility as needed.

We run a high-scale data service processing millions of AI generations daily, built with FastAPI (Python) on the backend and a data-intensive, visualization-heavy UI using TypeScript and React.

Our customers—AI teams at leading companies—expect top-tier performance, reliability, and intuitiveness. We aim to set the standard for design that enables product leaders and non-technical subject matter experts to seamlessly collaborate with developers on building AI.