Human-Centric x AI-Native
Design Engineering

A Design Engineer is a hands-on product expert who bridges UI/UX design and frontend engineering. They combine user experience design skillset with a solid frontend engineering background, turning ideas and designs into production-ready user interfaces. Instead of hiring separate UI Designer, UX Designer and Frontend Engineer, you work with one experienced builder who can take your product from concept to launch as well as prototype and iterate rapidly with you along the way.

Human-centric design means putting real user needs first. It combines the science of how humans perceive data in user interfaces with real customer needs to build optimised user experience for the users.

At Zuzze, every decision is shaped by human thinking to create products that are intuitive, meaningful, and bring value to users — not just AI-generated outputs. A range of proven industry methods, from design thinking, rapid prototyping,value proposition, heuristic usability evaluation, cognitive walkthroughs, user interviews, user research, and user testing are used to ensure the product truly resonates with its users and actually works for them, not just look nice.

AI-native means AI is built into the product and development from day one — not added later as a feature. Zuzze adds AI where it actually makes a difference integrating for example LLMs, agents, skills, RAG, Model Context Protocol (MCP), and generative AI in design and development workflows.

The result is faster product development while keeping humans in control as the final decision-makers.

Zuzze is a one-woman studio led by award-winning frontend engineer and UI/UX designer Susanna Nevalainen. You work directly with a senior expert with strategic partner mindset — no outsourcing, no hand-offs, no communication gaps.

Susanna has university degrees with honours in Computer Science as well as in Human-Computer Interaction & Design. Additionally, she has 10+ years of international industry experience from innovation teams, research centers, agencies and startups building products from zero to one. Learn more

For large enterprise-level systems, Susanna collaborates with top agencies in the US, Europe and Canada to bring even the most ambitious products alive. Susanna is also a Frontend Guild leader of US based a.team working alongside top Silicon Valley consultants ranking into top 1% of tech talent world wide.

AI vibe coding tools like Lovable, Figma Make etc. can generate code quickly, but at the end of the day they are tools — not a replacement of human thinking nor domain expertise.

If you solely rely on AI to take all design and code decisions on your behalf without understanding what's happening under the hood, you can end up with a nice prototype for demos but in reality this rarely compares with optimized, secure and scalable production builds designed by professional designers and developers. Trusting just AI can lead to high token costs, costly re-implementations, product delays and a lack of control over the final product.

Zuzze makes the best out of both worlds: over 10+ years of traditional design and frontend experience combined with proven AI workflows. This accelerates design and development with AI speed but keeps the door open for manual changes whenever AI gets stuck and starts hallucinating, making the human always the final reviewer and decision maker.

Deliverables and timelines are defined before we start. In most projects, you’ll receive tangible deliverables for feedback every week — from moodboards and wireframes to high-fidelity Figma designs, clickable prototypes, or working product. In sprints, you can expect daily updates enabling continous feedback loops for rapid iteration.

Product design deliverables and landing websites are usually delivered within couple of weeks while custom web app user interfaces typically take around 3-6 months from design to production.

Yes. Zuzze regularly helps teams improve products that are underperforming or broken due to poor usability or unscalable frontend architecture.

The typical starting point is a focused 1–2 day UX Audit covering design, user flows, design systems, and/or frontend implementation. You’ll get a clear, actionable plan for what needs to change without committing for months of re-implementation.

From there, you can move forward independently or continue with Zuzze to implement the suggested improvements.

Yes, while Zuzze can work independently as your fractional design/frontend partner, in many larger projects Zuzze regularly supports internal design and frontend teams by giving guidance and trainings along the way in addition to the hands-on foundational design and development work.

Yes, Zuzze is an award-winning ThreeJS developer and certified Spline Expert happy to help with design and development of 3D web user interfaces as well as immersive AR/VR user interfaces. Additionally, Zuzze is able to create 3D assets using AI workflows as well as manual 3D modeling in Blender or Spline.

The journey starts with a short conversation to understand your product and goals and see if we are a good fit. From there, we’ll define the scope, timeline, and deliverables — whether that’s a quick audit, a focused sprint or a full 0 → 1 build.