Agentic platform engineer in adtech

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. As our Agentic Platform Engineer, you will help build and scale Liz Agent, Seedtag's AI agent platform, ensuring reliability, security, and seamless integration across teams.

• Agent Platform Development: Build and maintain the core Liz Agent runtime, including agent execution, context management, and event streaming.
• Tools & Integrations: Develop MCP tool servers, APIs, and integrations that enable secure access to internal data and services.
• Agentic AI Capabilities: Improve agent functionality through memory, multi-model routing, durable execution, and LLM frameworks.
• Reliability & Observability: Monitor platform performance, troubleshoot production issues, and improve tracing and evaluation capabilities.
• Platform Engineering: Contribute to APIs, service templates, CI/CD pipelines, and cloud-native deployments that enable teams to build agents independently.
• Security & Quality: Implement security best practices, automated evaluations, and regression testing to ensure reliable agent behaviour.
• End-to-End Ownership: Take responsibility for features from development to deployment and monitoring, collaborating with Data, ML, Platform, and Product teams.

• 3+ years of experience building and maintaining backend systems in production.
• Strong Python expertise, including APIs, asynchronous programming, testing, and clean architecture.
• Hands-on experience developing LLM applications or AI agents, including tool calling, structured outputs, and evaluations.
• Solid understanding of event-driven architectures, microservices, Kubernetes, and cloud infrastructure.
• Experience with LLMOps, observability, CI/CD, and production troubleshooting.
• Knowledge of AI security practices, including authentication, access controls, and prompt-injection protection.
• Ability to own features end to end, work autonomously, and collaborate effectively with cross-functional teams.

• A key moment of growth with real ownership and global impact.
• Flexible work model with 100% remote or hybrid options.
• 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