We are a product team within Leadtech's AI-LAB. Our job is to research, prototype, develop, launch and scale challenging AI products across the Leadtech portfolio.

We're looking for a Senior AI Frontend Engineer who can launch a product and scale it: someone with experience in UX/UI design, A/B testing and product metrics, and who incorporates AI-native tools by default.

This is a frontend-first role with full-stack reach.

What You Will Do:
- Take new products from zero to launch and beyond. You'll be involved from ideation and research through prototyping, build, release and scale, owning features end-to-end.
- Prototype fast. Turn a concept into something users can click within days, put it in front of them, and double down or discard it based on what you learn.
- Scale what works. Once a product finds traction, you'll grow it: hardening the codebase for a larger user base, keeping performance and quality high as scope expands, and evolving features based on how real users behave.
- Own the frontend: architecture, component library, design system,



and the UX that make a great product.
- Design and build high-converting landing pages, checkout flows and paywalls. You'll work on the surfaces where revenue happens, achieving the best conversion will be part of your job.
- Bring AI into the development process itself. You'll design and integrate LLM-powered features into our products as well as create skills, automations and internal tooling that make the team faster.
- Ship to learn. Proactively instrument features, run experiments, read the funnel data, and iterate based on what you discover. You treat metrics as a compass.

What You Will Bring:
- 5+ years of frontend engineering, with deep TypeScript and React proficiency (Hooks, Context API, state management, Vite, Tailwind, Shadcn UI) and a track record of owning significant surface area.
- You have taste. You can distinguish between good and bad UX, articulate why, and share examples from your own work to dem

📌 Senior Ai Full Stack Engineer (Barcelona)
🏢 Leadtech
📍 Barcelona