We are looking for an AI Product Builder in Madrid: someone for whom thinking, designing, and building are not separate stages, but a single act. Someone who collapses the distance between idea and product until it becomes almost invisible. End-to-end, no intermediaries, no safe havens. You will work directly with the Data leadership and ship real impact from day one.

About the role

• Own consumer-facing AI products end-to-end: from identifying the opportunity, to designing the experience, to shipping the implementation, to measuring impact. No hand-offs.
• Embed AI across the full consumer flow - discovery, recommendations, conversion, retention, support - using LLMs, agents, and modern AI tooling as a native part of the product, not as a feature.
• Understand our business, our customers, our market, and the data behind our consumer product to delight users and achieve Fever's goals.
• Move fast with strong opinions: form a hypothesis, build the smallest thing that proves or kills it, ship, learn, iterate. Treat shipping as the way to think.
• Build prototypes and production-ready experiences yourself when needed, leveraging AI coding tools and modern development workflows to compress the idea-to-product cycle.
• Define the right metrics, run experiments (A/B tests, offline evals, online evals for AI features), and continuously improve product and model performance.
• Collaborate with stakeholders across Design, Growth, and the Tech team, working sid by side with a team of Software Engineers.
• Translate broad, ambiguous opportunities into concrete, measurable bets, and make sharp prioritization calls under uncertainty.
• Help shape the vision and strategy for AI in the consumer product, and bring it to life through what you ship.

About you

Basic skills and qualifications:
• Bachelor's degree in Engineering, Computer Science, or a related field.
• 3+ years of relevant experience building consumer-facing digital products end-to-end (as a builder, founder, full-stack PM, product engineer, or similar hybrid role).
• Proven, hands-on experience integrating AI / LLMs into real products in production - not just prototypes or demos.
• Solid experience in consumer products: you understand user behavior, funnels, conversion, retention, and what makes a consumer experience feel magical.
• Strong technical fluency: comfortable understanding system architecture, prototyping with modern AI tools, working with APIs, and holding deep technical conversations with the engineering team.
• Independent judgment and taste: you have your own criteria for what good looks like and defend it with arguments, not consensus.
• Precision and speed: you ship quickly without losing rigor, and you treat being wrong fast as a way to get closer to the truth.
• Strong quantitative and analytical skills - comfortable with data, metrics, and turning numbers into product decisions.
• Proficiency in English; able to communicate complex technical and product ideas clearly to any audience, in writing and in person.
• High sense of ownership, urgency, and drive in a fast-paced, ambiguous environment.

Preferred skills and qualifications
• Hands-on experience with the modern AI stack: LLM APIs (OpenAI, Anthropic, etc.), prompt engineering, RAG, evals, agentic workflows, and AI coding tools.
• Experience designing and running evaluations for AI-powered features (offline and online), and reasoning about model quality, cost, and latency trade-offs.
• Background in tech startups, or a strong willingness to operate inside a fast-moving, high-ambition tech company.
• Track record of shipping products as a small team or solo: founder, early-stage employee, indie builder, or similar.
• Strong product taste and design sensitivity - you care about how things feel, not just whether they work.
• Experience formulating hypotheses, building lean validations, running A/B tests, and defining primary and guardrail metrics.
• Strategic sense: ability to collaborate in defining where the consumer product and its AI surface area should go in the next 1-3 years.
• Ability to build trust quickly across different levels of an organization and rally people around what you are building.

Why join Fever

• You will have real ownership and visible impact.
• You will help shape products, systems, and capabilities that matter across the business.
• You will work in an environment that values ambition, adaptability, pragmatism, and execution.
• You will be surrounded by smart, driven people who care about building things that matter.

Benefits & Perks

• Flexible schedule
• 2 days per week at the office
• 40% discount on all Fever events and experiences
• Health insurance from Day 1
• English or Spanish Lessons
• Wellhub Membership
• Cobee (tax free allowance on restaurants and transport)
• Possibility to receive in advance part of your salary by Payflow