Principal AI Scientist (all genders)

Zalando SE; Berlin; Hybrid; EUR 120,000 - 190,000; Full time

Benefits offered by this job

Employee shares program

40% off fashion and beauty products

Hybrid working model

Relocation assistance

Health and wellbeing options

Mental health support and coaching

Vacation 27 days

Job summary

Zalando SE seeks a Principal AI Scientist to shape the Zalando Assistant, building production-grade AI agents and LLM-powered workflows for fashion discovery, recommendations, and conversational shopping.

You will own architecture, RAG pipelines, prompt engineering, and cross-functional collaboration with product, engineering, and data science teams. This hands-on leadership role emphasizes measurable business impact and responsible AI practices.

Qualifications

• 10+ years in engineering or applied science roles.
• Proven track record building production-grade AI systems.
• Experience with LLM-powered applications or agents is a plus.
• Strong Python experience and cross-functional collaboration.

Responsibilities

• Design and build conversational AI agents.
• Develop and integrate RAG pipelines for contextual data.
• Design, tune, and evaluate LLM prompts for quality and engagement.
• Integrate LLMs with search, recommendations, and APIs.
• Define evaluation frameworks for conversation grounding.
• Lead experiments and optimize KPI-driven agent performance.

Skills

Python programming

Analytical thinking

Problem solving

AI systems optimization

Mentoring & leadership

Tools

LangChain

LlamaIndex

PydanticAI

DSPy

Job description

ABOUT THE ROLE

Zalando’s Zalando Assistant team is looking for a Principal AI Scientist to help us build the future of retail through conversational AI experiences powered by Large Language Models (LLMs) and intelligent agents. Your expertise will be key in designing and developing AI-driven systems that support fashion discovery, trend exploration, outfit recommendations, and conversational shopping experiences. As a Principal AI Scientist, you’ll play a significant role in shaping the architecture and capabilities of the Zalando Assistant. You will work on AI agents, RAG pipelines, prompt engineering, and LLM integrations, ensuring high-quality, grounded, and engaging conversations. Your domain will span the full customer lifecycle, helping drive customer activation, engagement, retention, and conversion through intelligent conversational experiences. This is a hands-on role with direct impact on customer-facing experiences. You will build and improve production AI agents used by millions of customers, working closely with product and engineering partners to deliver measurable business impact through improved product discovery, recommendation relevance, and purchase conversion. You will be at the center of fostering a culture of experimentation and innovation, ensuring assistant improvements are rigorously evaluated using both offline and online metrics. Your work will directly influence business impact, improving engagement, retention, and long-term customer value through conversational AI.

INCLUSIVE BY DESIGN

At Zalando, our vision is to be inclusive by design. And this vision starts with our hiring - we do not discriminate on the basis of gender identity, sexual orientation, personal expression, ethnicity, religious belief, or disability status. You are welcome to leave out your picture, age, or marital status from your application. We only assess candidates on their qualifications and merit. We want to provide you with a great candidate experience. Feel free to inform us of any accommodations you may need, so we can best support you throughout the hiring process. do.BETTER - our diversity & inclusion strategy: https://corporate.zalando.com/en/our-impact/dobetter-our-diversity-and-inclusion-strategy Our employee resource groups: https://corporate.zalando.com/en/our-impact/our-employee-resource-groups

WHAT WE’D LOVE YOU TO DO (AND LOVE DOING)

• Design and build conversational AI agents


• Develop and integrate RAG pipelines to enrich experiences with fresh, contextual data


• Design, tune, and evaluate LLM prompts to improve response quality and user engagement


• Integrate LLMs with search, recommendation, and external APIs


• Define and implement evaluation frameworks for conversation quality and grounding


• Run experiments and optimize assistant performance for business KPIs (conversion, engagement, retention)


• Own the architecture, development, and deployment of LLM-powered agent workflows


• Collaborate cross-functionally with engineering, product, and data science teams


• Mentor colleagues and share best practices in applied AI and agent development

WHAT WE’RE LOOKING FOR

• 10+ years of experience in the field of engineering or applied science.


• Strong Python skills and experience building production-grade applications


• Strong analytical and problem-solving skills


• Experience optimizing AI systems for business KPIs


• Any of the following is a strong plus:


• Experience building LLM-powered applications or AI agents


• Experience with prompt engineering, tuning, and evaluation


• Experience with agent frameworks such as LangChain, LlamaIndex, PydanticAI, DSPy, or similar


• Experience integrating LLMs with external APIs, tools, and/or RAG systems


• Experience evaluating conversation quality and defining LLM metrics is a plus


• Experience with vector databases, embeddings, or retrieval systems

OUR OFFER

Zalando provides a range of benefits, here’s an overview of what you can expect. Ask your Talent Acquisition Partner to learn more about what we offer.

• Employee shares program


• 40% off fashion and beauty products sold and shipped by Zalando


• 30% off Zalando Lounge


• discounts from external partners


• 2 paid volunteering days a year


• Hybrid working model with 60% (or more) remote per week, actual practice is up to each team to best support their collaboration


• Work from abroad for up to 30 working days a year


• 27 days of vacation a year to start


• Relocation assistance available (subject to prior agreement)


• Family services, including counseling and support


• Health and wellbeing options (including Gympass)


• Mental health support and coaching available


• Drive your development through your training platform and biannual peer-to-peer review

Learn all about Zalando and our values here: https://jobs.zalando.com/en/?gh_src=22377bdd1us It’s the perfect time to join Zalando on our journey, from being a pioneer in the world of e-commerce, to the Starting Point for Fashion in Europe. We connect customers, brands, and partners across 25 markets. Help us drive digital and sustainable solutions for fashion, logistics, advertising and research, bringing head-to-toe fashion to 50 million active customers through a team of diverse skill-sets, cultural backgrounds, and interests. Our values do.More - our sustainability strategy Follow us on Instagram: instagram.com/insidezalando