Vector Search Engineer For Ai Retrieval & Data Systems

Fasts3 Inc. in Madrid is seeking Research Engineers who thrive at the frontier of data systems, vector search, and ML infrastructure. You’ll prototype new algorithms, validate performance, and bring innovations in retrieval and indexing into production.

Join a team that designs high‑performance vector stores, explores graph‑based retrieval, and builds RAG backends. You’ll scale prototypes to production and contribute to open research through implementation.