Data Scientist
Harmonic Security lets teams adopt AI tools safely by protecting sensitive data in real time with minimal effort. It gives enterprises full control and stops leaks so that their teams can innovate confidently. We are led by cybersecurity experts and backed by top investors including N47, Ten Eleven Ventures, and In-Q-Tel. About the Team Our Product Delivery team is the engine that turns vision into impact. We ship early and often, getting valuable features into the hands of customers quickly and iterating fast. We work in the open by default, sharing progress and ideas, and we trust each other to own outcomes. We’re a small but mighty crew where every person plays a critical role and we’re committed to using AI to work smarter and faster.
About the Role
As our Data Scientist, you’ll help advance our mission to secure Generative AI adoption by building and continuously improving the detection models at the heart of our product - curating high-quality training datasets and tuning production models informed by real-world customer feedback.
What You Will Do
You’ll build and improve sensitive data detection models end-to-end - defining new sensitive data categories, curating training and evaluation datasets, training and validating models, and shipping production-ready detectors. Once models are live, you’ll continuously improve our existing suite using model performance metrics and direct customer feedback to prioritise retunes and sharpen detection accuracy. You’ll communicate clearly and proactively in a remote/hybrid team - able to explain trade-offs, make recommendations, and bring engineering, security, and product partners along in decisions without slowing momentum. You’ll stay current on techniques that materially improve model and dataset quality, and you'll be directly contributing to the development of groundbreaking technology that empowers secure Generative AI adoption within enterprises. You'd Be A Great Fit For The Role If You’ve taken classification / NLP models from idea to production and owned them after launch - monitoring performance, tuning on real-world feedback, and improving results over time (not just training and handing off). You have strong applied NLP experience: transformers and embeddings, when fine-tuning makes sense, and when a simpler classical approach wins. You’ve built and managed high-quality training and evaluation datasets from messy real-world data - making hard labelling/taxonomy calls, and you can point to how dataset quality moved model performance. You run rigorous evaluation and care about precision/recall trade-offs, so we know a model is better before customers do. You’re expert in Python and comfortable in the modern ML stack (e.g. PyTorch, Hugging Face, scikit-learn). You’re a clear communicator who collaborates well across a remote/hybrid team, and you have a bias for shipping: pragmatic decisions, fast iteration, and incremental delivery. Bonus Points If You Have Experience in data security / sensitive-data classification, or adjacent applied security problem spaces. Experience working directly with customers/end-users to understand the problem domain and validate improvements. Experience operating ML systems in cloud environments (e.g. AWS). How We Work: AI-First by Design Harmonic exists to help enterprises adopt AI safely and at scale. We hold ourselves to the same standard. Everyone at Harmonic actively uses AI tools to do their best work, from research and writing to building processes and automating workflows. We expect every new hire to bring curiosity about AI and a willingness to use it to work smarter, faster, and more creatively. For some roles, that means tinkering and staying open to new tools. For others, it means building entirely new systems with AI at the core. We'll be clear about what we expect for each role, and we'll give you the tools and support to get there.
Why Join Us
This isn’t just a job; it’s an opportunity to be part of a team that is redefining cybersecurity. We believe today’s talent is tomorrow’s success, and we’re committed to creating an environment where you can do the best work of your life. Competitive pay and meaningful equity with a direct stake in Harmonic’s success Comprehensive benefits, pension plan, generous PTO, and flexible hybrid work A small, passionate team that values transparency, creativity, and learning Thoughtful leadership that cares deeply about growth, impact, and people Annual global off-sites (past trips include Lisbon and Nashville) The chance to directly shape both our product and our culture as we build a category-defining company Harmonic's Core Values 🌱 Flourish in the Unknown We embrace new, unfamiliar situations that require initiative and rapid decision-making. We orient ourselves quickly and deliver results with minimal guidance. 🔥 Never Full We raise our hands, take on challenges, and assist others whenever possible. We hunger for opportunities to learn and do more. 🤝 Perfect Harmony We support one another to create cohesion and unity. We collaborate openly, share feedback honestly, and help everyone produce their best work