Lead AI Scientist
Role details
Job location
Tech stack
Job description
Location: Berlin, Germany (hybrid - open to exceptional remote candidates)
This is not a role where you inherit a mature ML stack and optimize metrics at the margin. This is the chance to be the person who builds the core intelligence of an AI-first company from the ground up - to define what the models do, how they learn, and how they create value. At most companies, the lead data scientist is several layers removed from the product and the customer. Here, your models are the product.
The platform is live, the data is flowing, and the foundation is solid - your job is to own the intelligence that sits at the core of everything we do. Specifically, you will:
- Define the strategic roadmap for our core AI capabilities, from research and experimentation to production deployment.
- Develop, train, and deploy reinforcement learning models for real-time message optimization, using techniques like contextual bandits.
- Fine-tune and implement large language models to generate personalized and effective marketing content at scale.
- Design and execute large-scale randomized controlled experiments to measure the causal impact of our models on key business metrics.
- Collaborate with engineers to build scalable, production-grade MLOps pipelines.
- Translate business objectives into machine learning problems and drive the research of novel solutions.
You won't just run experiments in isolation, you will bring models into a production environment that demands low latency and high throughput. You will do all of this as part of a small, senior team at a founding stage, with a working product as your starting point and a broad vision that gives you real ownership over what comes next.
Requirements
Do you have experience in Python?, * You have an advanced degree in Computer Science, Statistics, Mathematics, or a related quantitative field.
- You have proven experience building and deploying machine learning models in a production environment.
- You possess deep expertise in reinforcement learning and/or natural language processing with large language models.
- You have experience leading technical projects or mentoring other scientists and engineers.
- You are proficient in Python and common machine learning libraries.
- You are an effective communicator who can explain complex technical concepts clearly and concisely.
- You work independently. You don't wait to be told what to research, you identify the highest-leverage problem and go solve it.
- You take full ownership from research through experimentation through production deployment.
- You focus on outcomes and use data and intellectual honesty to find the best solutions.
- Bonus if you have experience with causal inference, experimentation platforms, recommendation systems, building ML infrastructure at scale, or real-time model serving.
Benefits & conditions
- The rare opportunity to join an elite team of experienced builders and entrepreneurs who have done this before - founded, scaled, and sold an AI-driven SaaS business.
- A role where data science is not a support function - it is the core of the product and the business. Your work directly determines what we ship and how well it performs.
- Ownership of the core ML roadmap and the autonomy to make the research and technical calls that matter.
- Direct access to large-scale, real-world data from millions of consumer interactions, with a tight feedback loop to see the impact of your work in near real-time.
- A fast-paced, low-bureaucracy engineering culture where shipping models that move business metrics is the only thing that counts.
- An AI-native environment with the computational resources and tools to stay at the cutting edge.
- A growing engineering team - you will have real leverage, not carry the whole research agenda alone.
- A competitive salary and a meaningful equity stake - early enough to shape the company's direction, de-risked by paying customers and strong market traction.
