Backend engineer python in AI

One of the companies we work with at Joppy is looking for a Backend Engineer to join the team. We're looking for an experienced backend engineer with depth. You'll come from a Backend Engineering background - Python, APIs, distributed systems - but what matters most is your motivation to build across layers and solve complex problems end-to-end. Backend is your anchor, but this is a high-impact engineering position for someone who enjoys working with multiple parts of the system rather than in a narrow specialization. You'll work closely with our core team to design, build, and scale the backend systems that power large-scale AI-driven information verification and representation.

• Design and build backend services using Python (FastAPI)
• Architect data storage and retrieval systems using SQL and NoSQL technologies (Postgres, Redis, Cassandra, graph databases)
• Develop and maintain scalable pipelines (batch and streaming)
• Work with cloud infrastructure on AWS and containerized environments (Kubernetes)
• Experiment with emerging AI engineering tooling (coding agents, MCP ecosystems, etc.)
• Collaborate on system design and cross-functional architectural decisions
• Contribute to a culture of clean, pragmatic, high-quality engineering

• Strong background in: Backend Engineering (Python, APIs, distributed systems)
• Technical stack we commonly work with: Python
• FastAPI or similar frameworks
• AWS
• Kubernetes
• SQL and NoSQL databases (Postgres, Redis; Cassandra or graph databases are a plus)
• DevOps practices
• 4+ years of hands-on backend 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
• Curious about how things work end-to-end, including the parts adjacent to your own - infrastructure, data, the systems your code runs on
• 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)
• Будет плюсом: Cassandra or graph databases are a plus; Search systems or information retrieval is a nice to have; Builders at heart: hackathons, side projects, open-source contributions, active GitHub are all highly appreciated

• Competitive salary
• Stock options
• Hybrid model: 3 days per week onsite
• New office on Gran Via (Barcelona), with a full dedicated space.
• Flexible benefits covering transport, meals, and health insurance.