Junior & Senior Backend Developer Python

Nuestro cliente: startup tecnológica europea especializada en inteligencia artificial aplicada a entornos físicos de alto tráfico, como centros comerciales, aeropuertos, destinos de ocio y cruceros We’re looking for a Founding Senior BackEnd Engineer — someone who wants to design, build and own the entire backend and systems architecture . This is not a maintenance role. It’s a founding role , with high phantom-share compensation , where you will shape the core platform that powers real-time AI assistants used by millions of visitors across malls, airports, stadiums and resorts .

You'll own the backend, APIs, microservices, data flows, real-time orchestration, and ML integrations end-to-end —ensuring performance, security, and scalability as we expand across international portfolios. This role sits at the intersection of AI, product engineering, infrastructure, data architecture, and ML operations .

Requirements: Technical ~5+ years building backend systems at scale . ~ Strong expertise in Python (FastAPI o Django) , SQL (Postgres/MySQL), and REST/GraphQL APIs. ~ Experience with microservices and Cloud Run. (Kubernetes, Pub/Sub, queues, caching removed as requested) ~ Strong in schema design, migrations, indexing, performance tuning. ~ Experience integrating external APIs (OAuth, webhooks). ~ Familiarity with LLM integrations, retrieval pipelines, or vector DBs (Qdrant) is a plus. Product & Ownership Previously owned a backend/platform in a startup or led a technical project end-to-end .

Ability to act as tech lead when needed: drive decisions, review architecture, guide junior/mid engineers, and push delivery. Bias for simple, reliable, resilient systems . Autonomous, fast, and comfortable in messy zero-to-one environments. Clear communicator, proactive, opinionated, and hands-on.

Valued: knowledge of Typescript, Javascript, React (not required but appreciated). ¿Qué ofrecen?

• Súmate a un proyecto startup con alto potencial de desarrollo y escalabilidad • Oportunidades únicas de crecer y desarrollarte en una empresa en pleno crecimiento.
• Aprende e innova en un ambiente súper dinámico de startup.
• Modalidad híbrida (50% en remoto y 50% en oficinas de Barcelona).
• Contrato indefinido. 45-60k€ brutos/año en función de experiencia contrastada.
• This is not a maintenance role. It’s a founding role , with high phantom-share compensation , where you will shape the core platform that powers real-time AI assistants used by millions of visitors across malls, airports, stadiums and resorts .

Main Functions: Architect and own company’s backend & microservices end-to-end. Build scalable APIs, workers, queues, and real-time systems on GCP + Cloud Run + Cloud SQL . Implement integrations with CRMs, CMSs, booking systems, loyalty platforms, and external APIs.

Develop backend support for AI agents : retrieval APIs, embeddings, vector DB, inference services. Build and maintain event pipelines for analytics, ML, and product insights. Ensure system security, observability, monitoring, logging, and CI/CD best practices . Collaborate with Product & AI teams to define technical architecture and implement new features quickly. Own migrations, deployments, environments, CI/CD, and platform reliability.