Senior Software Engineer — Real-Time AI Backend (Barcelona)

Supersonik, Inc.; Barcelona; Híbrido; EUR 90.000 - 130.000; Jornada completa

Ventajas ofrecidas por este puesto de trabajo

Significant equity in a company backed

Full ownership, real impact

Fast learning cycles

A tight-knit team

Descripción de la vacante

Supersonik, Inc. in Barcelona is looking for Senior Engineers to join the core team. You will solve complex, technical problems and shape the product and architecture from day one, thriving in a high-growth startup.

Fluent in modern Python and async programming, you will build scalable, event-driven systems and work at the intersection of performance, AI and great user experience. If you love solving first-principles problems, navigating ambiguity and want to build a product people love you’ll

Responsabilidades

• Scale a real-time, event-driven backend architecture where milliseconds matter
• Design and implement low-latency APIs using FastAPI and Asyncio
• Solve engineering challenges in performance optimization, observability, and resilience
• End to end contributions from frontend to infrastructure
• Collaborate on prompt engineering, LLM behaviors, LLM fine-tuning and UX
• Build and maintain infrastructure-as-code with Terraform and AWS
• Contribute to 0→1 product development with a small, fast-moving team

Herramientas

FastAPI

Asyncio

Redis

PostgreSQL

AWS

Terraform

React

GitHub

Datadog

Linear

Descripción del empleo

Supersonik, Inc. in Barcelona is looking for Senior Engineers to join the core team. You will solve complex, technical problems and shape the product and architecture from day one, thriving in a high-growth startup.

Fluent in modern Python and async programming, you will build scalable, event-driven systems and work at the intersection of performance, AI and great user experience. If you love solving first-principles problems, navigating ambiguity and want to build a product people love you’ll