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# Senior Software Engineer

- **Company:** Seedtag
- **Location:** Barcelona, Spain
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Cloud Computing, Distributed Systems, Python (Programming Language), Node.Js, TypeScript, Large Language Models, Backend, Data Pipelines, Golang
- **Published:** October 24, 2026
- **Apply:** https://www.jobleads.com/es/job/senior-software-engineer--barcelona--eae5068f76a714155486db381840c5e62

## About the Role

Required skills include strong Golang experience, knowledge of distributed systems, AI technologies, cloud infrastructure, observability, and Infrastructure as Code. Experience with Python, Node.js, TypeScript, and AdTech (RTB, OpenRTB, CTV) is a plus.

## Description

Role Description

Seedtag is hiring a Senior Software Engineer to build backend systems for neuro-contextual advertising at scale.

Responsibilities

The role involves designing and maintaining high-throughput, low-latency services in Golang, integrating AI and ML models including LLM APIs, and developing scalable APIs and data pipelines for contextual data across OpenWeb, Connected TV, and in-app environments. The engineer will collaborate with Data Scientists, AI teams, and Product Managers to deliver impactful solutions.

Required Skills

Required skills include strong Golang experience, knowledge of distributed systems, AI technologies, cloud infrastructure, observability, and Infrastructure as Code. Experience with Python, Node.js, TypeScript, and AdTech (RTB, OpenRTB, CTV) is a plus.

Benefits

 * a home office budget
 * paid trips to HQ in Madrid
 * a MacBook Pro M3
 * continuous learning opportunities
 * a supportive culture

flexible remote or hybrid work options with contracts available in multiple European countries.