Principal Data Scientist

Responsibilities * Own real-time decisioning systems end-to-end. Alongside with Engineering, build and run robust services that pick game and ad configs; ship models as stable APIs/pipelines, handle retries and late data, keep clear targets with simple fallbacks, and roll out safely with quick rollback. * Keep modeling practical. Start with strong baselines, pick the right approach, test offline, then prove impact with controlled experiments. * Drive experimentation at scale. Define hypotheses and success metrics, run online experiments, and translate results into business decisions with quantified impact. * Partner across the org. Work closely with Product, Ads Monetization and UA to prioritize by impact vs. effort, align on objectives, and land outcomes. * Mentor & lead. Coach DS/DA teammates, review code/models/experiments, and raise the bar on scientific rigor and production quality. * Communicate clearly. Explain trade-offs and uncertainty to technical and non-technical stakeholders; turn findings into decisive actions. Requirements * 7+ years in data science, including 2+ years owning production ML systems at scale. * Strong scientific foundation: MSc/PhD in CS, Statistics, Applied Math, Physics or equivalent backgrounds. * Demonstrated experience with machine learning techniques, with solid experience in either supervised and unsupervised learning and/or deep learning frameworks (e.g.,TensorFlow, PyTorch, etc.). * Proficiency in Python and SQL; solid software engineering (testing, code review, profiling). * Familiarity with cloud-based data storage and processing platforms (e.g., AWS, Google Cloud Platform, or Azure). * Strong analytical and problem-solving skills, with a proven track record of translating complex data into actionable insights. * Ability to understand business needs across multiple teams and execute to achieve their targets. * Excellent communication and presentation skills, with the ability to convey complex information to both technical and non-technical stakeholders. * Professional-level English. Nice to have * Solid understanding of mathematical and algorithmic optimization approaches, and/or practical expertise applying those to real-world problems. * Production/MLOps experience: Docker, CI/CD, model serving, feature stores, monitoring & drift detection. * Streaming & services: GCP (BigQuery, Pub/Sub, Dataflow/Beam, Vertex AI, Cloud Run/GKE) or similar stacks. * Experience in data science in mobile gaming is a plus. What we offer * The Role: Own data science solutions from scratch with full autonomy. Join a meetingless company, no status updates, no sync calls, just deep work and results. * Location & Flexibility: Based in Barcelona (office with terrace, BBQ, beer tap). Flexibility policy: the data team comes in regularly because they want to, not because they have to. * Compensation & Perks: Competitive compensation based on experience, relocation package, health

About the Company Playvalve is a vibrant fast-growing gaming studio with an eye on the future. Our mission is to build fun and relaxing games meant to last, and we do that by bringing together a team of experts who love what they do. Our talented designers, artists, engineers, marketeers and analysts have created several games delivering joy and entertainment to over 20M users across more than 12 languages and 90 countries. About the Role As a Principal Data Scientist, you'll drive the data science strategy and ship the systems that make it real. You'll partner with marketing, product and ad monetization to turn rigorous science into production services. You own the journey end-to-end (problem framing, modeling, offline/online evaluation, serving and monitoring), establish engineering and scientific standards, and prioritize autonomously by impact vs. effort. You'll iterate on the company's data strategy while mentoring the junior team members and scaling the team capabilities. Key