Lead Data Scientist

PropHero; Madrid; A distancia; EUR 70.000 - 90.000; Jornada completa

Descripción de la vacante

A dynamic AI-focused company is seeking a hands-on Data Scientist Lead in Madrid to guide their AI/ML strategy and lead a small team. You will be responsible for developing ML models and ensuring production readiness. A proven background in classical ML and leadership experience is essential for this innovative role. The company offers a flexible work environment and an opportunity to contribute to significant projects.

Servicios

Flexible environment

Learning and development opportunities

Career growth in an early-stage startup

Formación

• 5+ years of experience as a Data Scientist/ML Engineer with hands-on coding.
• At least 1 year of leadership experience and mentoring skills.
• Strong background in classical ML lifecycle including training and testing.
• Practical experience with GenAI/LLM frameworks.
• Familiarity with MLOps practices.

Responsabilidades

• Lead and align a multidisciplinary AI/ML team.
• Design and optimize ML models for various tasks.
• Oversee pipelines for training and evaluation of models.
• Operationalize models for production systems.
• Explore solutions leveraging LLMs and generative AI.

Conocimientos

Coding in Python

Classical ML

Problem-solving skills

Communication skills

Leadership experience

Herramientas

scikit-learn

AWS

LangChain

HuggingFace

Descripción del empleo

At PropHero we are seeking a hands-on Data Scientist Lead to guide our AI / ML strategy and execution. This role combines deep technical expertise in classical machine learning with practical experience in generative AI, ensuring our solutions are both state‑of‑the‑art and production‑ready. You will be responsible for leading a small but powerful team, driving end‑to‑end development of ML models, and ensuring that PropHero continues to innovate across multiple product lines.

Responsibilities

Team Leadership & Strategy

Lead a small, multidisciplinary AI / ML team, ensuring alignment with product goals while fostering a culture of technical excellence.

Model Development

Design, implement, and optimize ML models for classification, regression, clustering, and forecasting tasks.

Training, Evaluation & Testing

Set up and oversee pipelines for training, evaluating, and testing models, ensuring robustness, accuracy, and reproducibility.

Inference & Deployment

Work with engineers to operationalize models, ensuring efficient inference and integration into production systems.

Generative AI Applications

Explore and build solutions leveraging LLMs, vector databases, retrieval‑augmented generation (RAG), and agent frameworks (e.g., LangChain, LangGraph).

Collaboration

Partner with AI Engineers, Data Scientists, and product teams to deliver practical, scalable, and impactful AI / ML features.

Innovation & Research

Stay ahead of industry trends in both classical ML and GenAI, translating cutting‑edge research into practical applications.

Mentorship

Provide guidance, code reviews, and knowledge sharing to support the growth of junior team members.

Requirements

Proven experience (5+ years) as a Data Scientist / ML Engineer, with hands‑on coding and model building.

At least 1 year of leadership experience – ability to mentor, review code, and guide a small team.

Strong background in classical ML (scikit‑learn, XGBoost, LightGBM, regression / classification / clustering algorithms, etc.).

Solid understanding of ML lifecycle: training, testing, inference and continuous evaluation.

Practical experience with GenAI / LLM frameworks (e.g., LangChain, HuggingFace, CrewAI).

Strong coding skills in Python, with ability to write clean, maintainable, and efficient code.

Experience designing experiments, with strong statistical foundations to ensure model robustness, fairness, and reproducibility.

Familiarity with cloud platforms (AWS preferred) and MLOps practices.

Excellent problem‑solving and communication skills, with the ability to work cross‑functionally.

Fluent English for effective communication in a distributed global team.

Benefits

We work remotely and in a flexible environment. This means we work with OKRs, always looking to grow the business, and we work with people worldwide, so we might have to adjust to different time zones.

Learning and development. No matter where you come from, no matter what you have studied, you will always have room to learn from others and develop yourself by participating in an open and transparent environment full of experiences and creative ideas.

Great Teamwork

• If you join us you will be part of a growing strong team composed of different levels of seniority, where decision and ownership is shared.

Early-stage Startup and opportunity for career growth

You will be part of the growth of a powerful startup with international projection and you will be able to gain more responsibility.

Competitive economic package.

Equal Opportunity Employer

At PropHero, we are committed to fostering an inclusive and equitable workplace where diverse perspectives and backgrounds are not only welcomed but celebrated. We believe that diversity drives innovation and empowers us to build stronger connections with our clients and communities.

PropHero is an equal opportunity employer and is dedicated to ensuring a hiring process free from discrimination based on race, ethnicity, gender, age, disability, religion, sexual orientation, or any other characteristic protected by law. Our mission is to create a workplace where everyone feels valued, supported, and empowered to achieve their full potential.