Senior Data Scientist

OLX

full-time

Posted on: 10/23/2025

Location Type: Remote

Location: Remote • 🇪🇸 Spain

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Senior

PythonSQL

About the role

Work in the Data Science team, focusing on LLMs and GenAI, from a platform and marketplace perspective.
You will build models, tinker around them to make them work, test them, and eventually deploy them to production. You will see your stuff in action and you will be able to measure the true impact of your models
You will maintain strong relationships with stakeholders. This means asking a lot of questions to business people and translating their requirements into achievable projects. It also means collaborating with other teams, like infrastructure and data engineering to get things done in an elegant and timely manner.
Partner with Engineering and Product to deliver solutions (customer-facing and platforms) to our customers (internal and end customers)
Work with Product Analytics to track the KPIs of different ML use cases and measure the impact on our customers.
Partner with the Experimentation team to integrate the KPIs and their proxies into the Experimentation (A/B testing) platform.
You will work in multi-functional teams, in a diverse, multinational environment, filled with people from Portugal, Bulgaria, Romania, Poland, Ukraine, Kazakhstan, and Uzbekistan.
Most importantly, you will have fun working with us :)

You must be located in Barcelona.
Solid background in statistics and modeling.
Good knowledge of Python, which means having experience with the most common data packages and libraries as well as the ability to develop and maintain simple services.
Experience with AI Agents frameworks (Pydantic AI, Google ADK, Langchain, etc.).
Experience with LLM observability, evaluation and tracing concepts (LLM as a judge, sampling monitoring, etc.) and frameworks (Langfuse, Arize AI, etc.)
Hands-on experience with Machine Learning (supervised, unsupervised, etc.).
Very good knowledge of NLP and Deep Learning (Embeddings, Language Models, Transformers, etc.).
Good knowledge of Generative AI and Large Language Models (LLMs).
Good understanding of engineering best practices, that is: testing, CI/CD, monitoring, alerting, and containers.
Hands-on experience with SQL.
Experience with MLOps.
Proficient in English with excellent written and oral communication skills!
Strong presentation skills.
Able to work in diverse, multi-functional teams with people from different backgrounds.

Benefits