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Junior Data Scientist

Remote, Barcelona·Added 4 days ago (last checked 15 Oct)

Seedtag

12 open roles

Overview

Work mode
Remote (Barcelona)
English
Required
Education
University degree

Visa options

  • The ad rules out sponsorship

    The advert says visa sponsorship isn’t available for this role.

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Skills

Requirements

What we're looking for

  • 0-2 years of experience in Data Science, Analytics, or Machine Learning, including internships, research, or personal projects.

  • Degree in Computer Science, Mathematics, Statistics, Engineering, or a related quantitative field, or equivalent practical experience.

  • Strong Python and SQL skills, with a solid understanding of statistics, machine learning, and model evaluation.

  • Hands-on experience building LLM-based agents or agentic workflows, including tool calling, structured outputs, or multi-step processes.

  • Good software engineering practices, including Git, testing, and clean, reproducible code.

  • Strong analytical thinking and data storytelling skills, with the ability to communicate insights to non-technical stakeholders.

  • Curious, proactive, and eager to learn, with professional working proficiency in English.

Pay & benefits

What you'll get

  • A key moment of growth with real ownership and global impact.

  • Flexible work model with 100% remote or hybrid options.
    (Remote contracts available in Spain, Italy, UK, Belgium, Netherlands, France, and Germany.)

  • Continuous learning through a learning platform and optional language classes.

  • A supportive, trust-based culture that values well-being.

  • Team activities, offsites, and opportunities to connect beyond work.

  • Home office setup budget up to €1,000

  • Paid trips to our HQ in Madrid

  • MacBook Pro M3

The role

We're looking for a [Job Title] to join our tech team and help build the future of neuro-contextual advertising at global scale.

What you'll do

As our Junior Data Scientist, you will join our Insights team to transform contextual, audience, and campaign data into actionable insights for clients and commercial teams, leveraging Liz, Seedtag's AI.

Your main responsibilities will include:

  • Data Pipelines & Analytics: Build and maintain pipelines to analyse campaign performance, audience behaviour, and contextual data across the open web and CTV.

  • Analytical Models: Develop models for audience profiling, content analysis, campaign comparisons, and pre-campaign planning.

  • Data Products: Turn analyses into scalable data products using tools such as dbt, Trino, and Airflow, ensuring data quality and reliability.

  • AI Agents & Automation: Prototype LLM-based agents and workflows using techniques such as embeddings, classification, clustering, and summarisation.

  • Experimentation & Evaluation: Design and evaluate experiments to ensure automated insights are accurate, reliable, and actionable.

  • Data Quality & Troubleshooting: Investigate data anomalies, identify root causes, and improve pipeline reliability.

  • Data Storytelling: Communicate findings through clear visualisations and actionable recommendations for Product, Sales, and clients.

Our Core Values

Outcome over Output
We measure success by impact and value, not by volume of features or lines of code.

Failure Is Allowed, Learning Is a Must
Experimentation is key to innovation. We test early, iterate often, and learn fast.

We Are All Scouts
We take ownership and leave things better than we found them.

We Are Data-Driven
Data informs our decisions and helps us continuously improve our systems and results.

Tech Stack

You'll work with modern data and AI technologies to build scalable insights products.

Our stack includes:

  • Languages & Libraries: Python, SQL, pandas, NumPy, scikit-learn.

  • Data Engineering: dbt, Trino, Airflow.

  • AI & Machine Learning: LLMs, AI agents, embeddings, classification, clustering, NLP.

  • Agent Frameworks: LangGraph, PydanticAI, MCP, OpenAI and Claude Agent SDKs.

  • Cloud & Data Platforms: GCP, BigQuery.

  • Development Tools: Git, unit testing, code review.

Hiring process

At Seedtag, we create an environment where everyone can thrive. If you need accommodations during the hiring process, let us know and we'll ensure a positive experience.

Send us your CV and let's build the future of neuro-contextual advertising together.

About Seedtag

Seedtag is a global advertising technology company specializing in contextual AI solutions. Founded in Madrid, Seedtag has grown into one of the leading independent adtech firms in Europe, with a strong focus on privacy-friendly, cookie-free advertising. The company operates in over 20 countries and serves major brands and publishers, leveraging its proprietary AI to deliver highly relevant ads based on content context rather than user tracking.

In Spain, Seedtag maintains its headquarters in Madrid, where a significant portion of its product, engineering, and commercial teams are based. The company is known for its innovative and collaborative culture, attracting international talent across engineering, product, and marketing roles. For international professionals, Seedtag offers the opportunity to work in a fast-growing, global adtech environment while being based in one of Europe's most vibrant capitals.

Industry
AdTech
Founded
2014
Employees
500–1,000
Headquarters
Madrid, Spain
In Spain
Madrid

Good to know if you are moving

  • Seedtag is headquartered in Madrid, offering international hires the opportunity to work in Spain's capital with a global team.
  • The company has a strong focus on AI and machine learning, providing opportunities to work on cutting-edge adtech solutions.
  • Seedtag operates in over 20 countries, giving employees exposure to international markets and clients.
  • The company is known for its flexible work culture and has been recognized as a great place to work in Spain.
  • Seedtag offers relocation support for international hires, including visa assistance and onboarding programs.

In their own words

About the company & team

At Seedtag, our mission is to transform advertising by proving that effectiveness and user privacy can truly coexist.

As the leading Neuro-Contextual Advertising Company, we combine Artificial Intelligence, Natural Language Processing, Computer Vision, and neuroscience to understand not only what content is about, but how it makes people feel and what they intend to do next.

Our proprietary AI, Liz, enables brands to connect with audiences across the open web and Connected TV without cookies or user tracking. Founded in 2014 by two ex-Googlers, Seedtag has grown to 500+ Seedtaggers in 17 countries, backed by €250M in funding, and operates today as a global ad-tech leader.

If you enjoy solving complex engineering challenges and building AI-driven systems at scale, you'll feel right at home here.

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