At Wellhub (formerly Gympass) (Permanent), in Lisbon, Portugal Expires at : 2025-12-09 Remote policy : Full remote We are hiring a Senior Data Scientist for our AI Engine team in Portugal! We seek a talented and motivated Data Scientist to join our team in Brazil / Portugal and contribute to groundbreaking projects in Generative AI. In this role, you will help shape the future of AI-powered wellness solutions by leveraging Generative AI, fine-tuning LLMs, and evaluating Agentic systems. As a Data Scientist in the CARE team, you will be at the forefront of innovation, developing cutting-edge Agentic AI that enhances and personalizes the wellness journey for millions of Wellhub subscribers. Your work will directly impact the role of AI in wellness, making it more adaptive, impactful, and transformative. You will collaborate with a multidisciplinary team of engineers and domain experts to create innovative AI applications and solve real-world problems. YOUR IMPACT Model Development & Fine-tuning: Understanding state-of-the-art deep learning techniques, such as Transformers architectures and attention mechanisms, and knowledge of fine-tuning LLMs using techniques like LoRA, QLoRA, among others. Function Calling & Tool Use: Design and implement structured function calling mechanisms within LLMs to enable dynamic interactions with APIs, databases, and retrieval-augmented generation (RAG) pipelines. Prompt Engineering: Craft clear instructions to help models understand exactly what is needed, creating reusable templates and testing edge cases. Data Preparation: Preprocess, analyze, and curate high-quality datasets for training and fine-tuning embedding and generative models. Evaluation and Testing: Develop evaluation frameworks to assess AI performance, including automated evaluation, adversarial testing, human-in-the-loop evaluations, and behavioral metrics. LLM Observability: Establish monitoring systems to track LLM behavior in production, capturing metrics like hallucinations, latency, and information retrieval quality. Research and Innovation: Stay updated with the latest research, share insights, test promising approaches, and contribute to team knowledge. Deployment: Collaborate with engineering teams to deploy models in scalable, efficient production environments. Live the mission : Inspire and empower others by genuinely caring for your wellbeing and your colleagues. Foster a work environment that prioritizes wellbeing, work-life balance, and support. Main requirements Master’s degree or PhD in Computer Science, Data Science, Machine Learning, Statistics, or related field. Proficiency in Python and experience with ML frameworks like PyTorch, TensorFlow, or similar. Strong understanding of generative AI architectures, transformers, and attention mechanisms. Experience with multi-agent systems and LLMs. Strong problem-solving skills, with a focus on experimental design and data analysis. Excellent communication skills to explain complex concepts to non-technical stakeholders. Clear scientific thinking and passion for integrating R&D and cutting-edge technology into products. We encourage applicants to apply even if they don't meet 100% of the requirements. Prior experience in Python and SQL is mandatory for this role. Our benefits include: WELLHUB: Access to digital fitness programs, wellness resources, and discounted premium plans. FLEXIBILITY: Hybrid or full remote work options, home office stipend, and flexible work hours. PAID TIME OFF: Minimum of 25 days holiday plus additional days based on tenure. PARENTAL LEAVE: 100% paid parental leave and extended maternity leave. CAREER GROWTH: Opportunities for personal and professional development. CULTURE: A supportive, global, high-growth environment focused on trust, flexibility, and integrity. J-18808-Ljbffr