Product / Full-Stack Engineer, Coaching and Review UX
This role helps build Lucy, the proactive AI coach from Lucy Labs that lives on your desktop as a cloud-backed app, while the product is in development with design partners.
Makes what Lucy infers correctable, explainable and worth trusting.
About the role
At Lucy Labs, this role owns the purpose described below.
The Product / Full-Stack Engineer for Coaching and Review UX builds the user-facing loops that make Lucy's Work Modeling system correctable and useful: coaching delivery, user corrections, explainability, feedback surfaces, admin review tools, and trust-aware product workflows.
This role makes evaluation and correction real product surfaces, not internal dashboards. Without it, Lucy can infer work but cannot let users shape, trust, and improve those inferences.
The mission
At Lucy Labs, this role's mission is defined by the outcome and work below.
Build product surfaces that:
- Let users correct Actions, Tasks, Goals, and Workflow candidates
- Deliver coaching in context without feeling intrusive or surveillant
- Explain why Lucy inferred something and what evidence supports it
- Give admins and reviewers usable controls for trust and quality
- Convert eval outcomes and user corrections into product learning loops
What you'd own
At Lucy Labs, this role turns its mission into concrete responsibilities in each area.
1. Coaching and Correction UX
For 1. Coaching and Correction UX, Lucy Labs expects this role to own the responsibilities below.
- Build coaching delivery surfaces across web, desktop, and notification contexts
- Build correction flows for task/goal/workflow candidates
- Design feedback capture that helps inference and eval systems improve
- Partner with Design on consent, explanation, and trust patterns
2. Review and Admin Tools
For 2. Review and Admin Tools, Lucy Labs expects this role to own the responsibilities below.
- Build admin review queues for inferred work, quality flags, and customer-specific vocabulary
- Create internal and customer-facing views that support governance without overwhelming users
- Implement role-based access and policy-aware UI states
- Support enterprise design-partner workflows
3. Full-Stack Product Engineering
For 3. Full-Stack Product Engineering, Lucy Labs expects this role to own the responsibilities below.
- Build high-quality frontend and backend product features
- Integrate with behavior inference, KG, eval, and trust APIs
- Maintain observability for correction, coaching acceptance, and review outcomes
- Keep interaction latency low enough for daily use
4. Product Learning Loops
For 4. Product Learning Loops, Lucy Labs expects this role to own the responsibilities below.
- Instrument coaching usefulness, correction rates, and user trust signals
- Partner with Product Research and Data/Evaluation on what feedback means
- Help turn repeated corrections into product decisions and system improvements
- Prevent UI shortcuts from hiding uncertainty or policy state
What success looks like
Lucy Labs defines these milestones as role outcomes, not metrics for measuring the person.
- 60 days
- Correction-loop prototype exists for the first Work Modeling candidates
- 90 days
- Coaching and review surfaces are instrumented and usable by design partners
- 6 months
- User corrections measurably improve inference and product trust
- 12 months
- Coaching and review UX becomes a core product differentiator
Experience and fit
Lucy Labs looks for the essential experience listed here and treats the rest as helpful, not an automatic barrier.
Must have
- 4+ years full-stack or product engineering experience
- Strong frontend craft plus backend/API integration ability
- Experience building feedback loops, review tools, workflow products, or admin surfaces
- Product judgment around ambiguity, user trust, and progressive disclosure
- Strong collaboration with design, product, data, and platform teams
Nice to have
- Experience with AI-assisted products, explainability, or human-in-the-loop workflows
- Desktop/web hybrid product experience
- Enterprise admin, audit, or review workflow experience
- Design systems or interaction design fluency
How you work
Lucy Labs looks for these working traits alongside technical experience.
Role DNA
Lucy Labs evaluates these traits as part of the fit for this role.
- User-trust focused
- Strong product taste
- Fast builder with quality discipline
- Comfortable exposing uncertainty honestly
- Collaborative with research and design
Apply for this role
The Lucy Labs application form opens with this role already selected. You can review the message before sending it.
Apply for this roleFrequently asked questions
Is this role open at Lucy Labs?
Yes. Lucy Labs confirmed this role is open on 25 August 2026.
Where does Lucy Labs base this role?
Lucy Labs bases this role in Madrid, Spain. The exact working arrangement is confirmed during the application conversation.
What does this role own at Lucy Labs?
At Lucy Labs, this role has one central responsibility: Makes what Lucy infers correctable, explainable and worth trusting. The full description sets out the mission, responsibilities, and relevant experience.
How do I apply to Lucy Labs?
At Lucy Labs, use the application form. The role is selected automatically, and you can review it before sending.
