We’re looking for a Senior Software Engineer - AI Agent Platform to join our tech team and help build the future of neuro-contextual advertising at global scale.

Who We Are

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 700+ 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.

Your Challenge

As a Senior Software Engineer - AI Agent Platform, you will:

• Design and build an enterprise-grade AI agent platform that handles real workloads, real users, and real constraints.

• Own critical parts of the platform: agent orchestration, memory and context systems, tool integration layers, and external communication protocols.

• Solve problems like managing conversation context at scale, coordinating multi-agent workflows, optimising LLM interactions, and exposing agent capabilities through standard protocols.

• Make architectural decisions that balance performance, maintainability and developer experience.

• Work closely with data scientists and product teams to ship agent capabilities that drive business outcomes.

This space moves fast. Frameworks, protocols, and best practices evolve constantly. We build solid foundations but stay ready to adapt. You should be comfortable with change and eager to stay at the state of the art.

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.

What You’ll Need to Succeed

• 5+ years building and operating backend systems in production, with strong distributed systems fundamentals.

• Proficiency in Python and ideally Go. You care about code quality and maintainability.

• Hands-on experience building LLM-based applications or AI agent systems using agent SDKs and frameworks (Pydantic AI, LangGraph, OpenAI Agents SDK, or similar).

• Experience with Kubernetes, GCP or AWS, observability tools, CI/CD pipelines.

• Understanding of agent patterns: tool calling, context management, and multi-step workflows.

• Experience working with AI-assisted development tools.

• Strong judgment and communication skills. You navigate ambiguity and make sound technical decisions.

• Track record of owning projects end-to-end in fast-moving environments.
  
  

Why Join Seedtag?

• 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.
  
  

Additional Perks

• Home office setup budget up to €1,000

• Paid trips to our HQ in Madrid

• MacBook Pro M3
  
  

Ready to Join the Seedtag Adventure?

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.