Software Engineer - Data Engineer

About the Position

We are looking for a Software Engineer - Data Engineer to join our team at Cala. Cala is building the knowledge layer for the future of AI, transforming raw public data into a trusted knowledge graph that any AI agent can query. We're based in Barcelona and San Francisco, and we're at an early stage where every new member helps shape our technology and culture.

About the Role 💡

We're seeking a Data Engineer to build the data foundation of Cala. Your role will involve designing and scaling pipelines that collect, clean, connect, and verify large amounts of data, and delivering this data to enterprise customers in production. You'll work across the entire system, from data ingestion to the knowledge graph, embeddings, and search, with real ownership over how it is built.

Responsibilities 🛠️

• Design and maintain scalable, high-throughput data pipelines and ETLs (batch and streaming)
• Architect data storage and retrieval systems using SQL and NoSQL technologies (Cassandra, graph databases) for efficient processing
• Collaborate closely with the team on system design and data modeling
• Work with cloud infrastructure on AWS and containerized environments (Kubernetes)
• Integrate and experiment with ML-based data representation techniques and emerging AI engineering tooling
• Contribute to a culture of clean, pragmatic, high-quality engineering

Requirements 🔎

Strong background in:

• Data Engineering (big data pipelines, storage systems, processing frameworks)

Technical stack we commonly work with:

• Big data pipelines (Spark, Hadoop, Kafka or equivalent)
• Python or Scala (Java welcome)
• AWS
• Kubernetes
• SQL and NoSQL databases (Cassandra a plus)
• Search and graph databases (Elasticsearch, Neo4j) are a nice to have
• DevOps practices

Profile:

• 4+ years of hands-on data engineering experience, with real depth – you've gone deep, not wide and shallow
• Able to reason about and justify your technical decisions: pros, cons, why A over B
• Builders at heart: hackathons, side projects, open-source contributions, active GitHub are all highly appreciated
• Curious about how things work end-to-end, including the parts adjacent to your own – infrastructure, backend, the systems your data feeds
• Curious about the AI ecosystem and modern developer tooling
• Comfortable in a fast-moving startup environment
• C1+ level in either English or Spanish (fluency in either is acceptable)

Why Cala? ✨

• Work alongside founders with a proven track record in AI and startups
• Build foundational AI systems with an "AI for good" focus
• High ownership, high autonomy, real technical challenges
• Join at an early stage and help shape both technology and culture
• A supportive, inclusive, and horizontal team environment

Locations

• Barcelona, Spain
• San Francisco, United States

Employment Type

• Full-time

Experience Level

• Senior

Work Location Type

• On-site