Senior AI Engineer

Senior AI Engineer (LLM, NLP)

Build LLM‑powered products at the forefront of marketing and advertising AI.

We're a well‑funded, fast‑moving startup (Series B, $43M) with engineering based in Europe. You'll own the LLM stack, work with cross‑functional teams, and shape the future of AI‑driven marketing for enterprise brands.

Location: Berlin

What you'll do

• Lead LLM development -- Train, fine‑tune, and deploy large language models for complex NLP tasks (marketing & advertising domain).
• Build robust architecture -- Implement scalable, production‑ready systems for LLM inference, monitoring, and continuous improvement.
• Evaluate & optimise -- Improve accuracy, efficiency, reliability. Tackle data quality, bias mitigation, and interpretability.
• Stay current -- Follow latest NLP/AI research, run experiments, prototype new ideas.
• Collaborate -- Work with application engineers, product managers, and designers to shape impactful solutions.
• Mentor -- Guide junior team members and foster a culture of innovation.

Who you are

Must‑haves:

• Industry experience deploying LLMs or large NLP models in production -- not just research or side projects.
• Strong Python and ML frameworks (PyTorch, TensorFlow, or similar).
• Deep understanding of machine learning, NLP, and LLM fine‑tuning / training.
• Data skills -- preprocessing, feature engineering, model evaluation techniques.
• Problem‑solving -- analytical, creative, and able to tackle ambiguous challenges.
• Communication -- explain complex technical concepts to non‑technical stakeholders.
• Location -- based in Germany (Berlin or remote within Germany).

Nice to have (not required):

• Experience with marketing tech, ad tech, or brand safety.
• Track record of published research or open‑source contributions in LLMs.
• Mentorship/leadership experience.

Why you'll love this

• Ground floor -- Join a fast‑moving startup at the center of the AI marketing revolution.
• Ownership -- You'll hold direct responsibility for the LLM technology stack.
• Impact -- Your work will be used by enterprise brands.
• Experienced team -- Industry veterans who previously built foundational ad‑tech platforms.
• Flexibility -- Hybrid in Berlin or fully remote within Germany.
• Growth -- True meritocracy. Career upside as the business scales.

How we hire

1. Screen (30 min) -- Talk about your LLM deployment experience and technical depth.
2. Technical interview (1h) -- ML/NLP fundamentals, LLM fine‑tuning, production challenges.
3. Take‑home or live coding (optional) -- Small LLM‑related task.
4. Team interview (1h) -- Meet engineers and product managers.
5. Offer