Founding Design Engineer in City of London

The one who designs by building. Not the one who designs in Figma and hands it off. The one who sketches an idea, builds it in code, puts it in someone's hands, and knows within hours whether it's right. The one who can't stand the gap between imagining an experience and feeling it work. The one whose portfolio is full of things that ship, not things that got presented. You don't own a step in the process. You own the result.

Healf is Europe's fastest-growing company. Number one on the FT1000, number one on the Sifted 100. From £1m to over £100m in under three years, with a small, talent-dense team and an electric culture with day one founder intensity. Now we're aiming for £1bn in the next three.

We curate the world's best wellbeing brands across The Four Pillars™: EAT, MOVE, MIND, SLEEP. That’s the first chapter. The next chapter is harder and more interesting. We are moving from one market to many, from e-commerce to a technology platform, and from curating wellbeing to defining it. We are a health company, so we think we should act like one. At its fullest expression, Healf redefines what wellbeing means for tens of millions of people.

Why this role is Healf: Healf is building Wellbeing Intelligence. A product that learns what works, for whom, and why, from the behavioural data of over half a million customers. It will personalise wellbeing decisions, close the feedback loop between what people do and how they feel, and get smarter with every interaction. That product does not exist yet. Not at Healf. Not anywhere.

The most important question right now is not how to build it. It is what should it be? How does it earn trust with something as personal as your health? How does it show you data about your own body without creating anxiety? Those are design questions. But the best answers will not come from mockups. They will come from prototypes that move, respond, and feel real. They will come from someone who designs by building, tests by shipping, and iterates by watching real people use real things. This is the role that answers those questions.

What you will own:

• The product, from first principles. You will define what Wellbeing Intelligence looks and feels like as a lived experience. The mobile app. The core surfaces. The interaction model. The emotional register. Not by inheriting a brief, but by thinking from the user's life inward. What does it feel like to be someone who wants to be well and doesn't know where to start? Start there. Design it. Build it. Test it. Learn.
• The design system, from scratch. Components, patterns, standards. You will build the foundation that every designer and engineer after you builds on. These are decisions that need to hold at ten times the scale without overbuilding for a future that hasn't arrived yet.
• The language and culture of design at Healf. How does Healf feel as a digital experience? Clinical or warm? Minimal or rich? Expert or approachable? You will define the product language and defend it. You are the first design engineer here. Every decision you make in the first six months becomes precedent. The tools, the workflows, the relationship between design and engineering, how research happens, how prototypes become production. You are not joining a design culture. You are creating one.

Why this role is at the frontier:

The best design decisions start in Figma and finish in code. The details that matter most, the ones that earn trust, only reveal themselves through implementation. AI has accelerated this shift. A design engineer on the frontier can now go from insight to working interactive prototype in hours. Not a wireframe. Not a clickable mockup. A real, responsive, testable experience that teaches you whether the idea is right before anyone has written a spec.

This means one person can now do what used to take three: think, design, build, test, iterate, ship. Not because they're cutting corners. Because the tools have collapsed the distance between intention and artefact. The designer who has fully embraced this shift has a different creative metabolism. More repetitions means sharper instinct. More options means better taste. Faster testing means higher confidence.

Healf is a small team building a product from nothing. We are not hiring a designer and three frontend engineers and a product manager. We are hiring one person who can move at the speed this moment makes possible. If you are not on the frontier of this shift, this role is not for you. If you are, there may not be a better place to apply it.

What success looks like:

• A design language for Wellbeing Intelligence that is distinctive, coherent, and earns trust with users.
• A working design system that engineers build with and future designers will build on.
• Multiple cycles of prototype-to-test-to-learn completed at a pace that would be impossible in a traditional design-to-engineering pipeline.
• Users who describe the product experience in emotional terms, not functional ones.
• A clear, opinionated point of view on what the product should become next, backed by evidence from real usage.
• An animation that runs at 60fps on a three-year-old Android, not just on your MacBook.

Why you are Healf:

You design by building. The gap between imagining something and experiencing it is physically uncomfortable to you. You need to see it move, feel it respond, watch someone use it. You prototype in code because that's where the real design decisions happen. In the nuances that don't exist in static vectors.

There is no correct background. You might have come from design and taught yourself to build. You might have come from frontend engineering and developed taste. You might have come from somewhere else entirely. The path is irrelevant. The output is everything.

You have a trail of things you've made. Not just a portfolio of screens. Actual things. Side projects, open-source components, personal sites that are themselves demonstrations of craft. When someone visits your work, they don't just see what you've designed. They feel how you think.

You think in systems but you obsess over moments. The system creates consistency. The moments create feeling. A scroll that decelerates just right. A transition that makes the user feel oriented rather than dislocated. A loading state that somehow makes waiting feel intentional.

You have been the first. Maybe the first hire. Maybe a founder. Maybe the person at an early-stage company whose work determined whether the product survived. You know what it feels like when there is no design system, no established process, no one to validate your decisions. You prefer it that way.

You have strong opinions and you defend them without being precious. You push back on engineering when the implementation drifts. You push back on product when the brief is wrong. You push back on yourself when the first version isn't good enough.

Craft, for you, is not just visual. You care that the animation performs, not just that it looks good. Cross-browser consistency. Accessible to assistive technology. Responsive to every input mode. Page speed. The work behind the pretty pixels is where trust is actually built.

You are already at the frontier. You read everything above about AI and the shift in design engineering and nothing surprised you. The only question is how far you can push it.

Show us:

• Something you made outside of work. A side project, an open-source component, a personal site that demonstrates how you think and what you care about.
• A product you designed and built where you can show the thinking and the code, not just the screens. The problem, the decisions, the tradeoffs, the result.
• A prototype you built in code that was tested with real users. What did you learn that you couldn't have learned from a mockup?
• Evidence you have worked at the zero-to-one stage: no design system, no established patterns, everything to define. What did you build and what did you decide?
• A moment where the details mattered and you got them right. Not the big product decision. The interaction, the animation, the micro-moment that most people would have shipped without noticing. You noticed. Show us.
• Examples of how AI tools have changed your actual workflow. Specific work you shipped faster, better, or differently because of them. Not opinions. Artefacts.

The deal:

We ask a great deal of the people who work here. We expect full ownership and a genuine commitment to give this chapter everything you have. In return, we will give you the same: everything we have, invested in your growth, your wellbeing, and the defining skills of the next decade.

We have built the fastest-growing company in Europe with a team small enough that every person in it shapes the outcome. That is still true today. The next person we hire will change the trajectory of the company. If the most important work of your career is ahead of you, this is the place to do it.

One question: Send your CV, a link to your work, and 200 words on this: You are building the first prototype of Healf's Wellbeing Intelligence app. A new user opens it for the first time. They want to feel better but they don't know where to start. Describe the first interaction: what it does, how it feels, and how you would build and test it within a week. We want to see design thinking and build thinking in the same breath.