Senior Software Engineer - Backend (Applied AI)

Aircall is a unicorn, AI-powered customer communications platform used by 22,000+ companies worldwide. Aircall's AI Voice Agent automates routine calls, AI Assist streamlines post-call work, and AI Assist Pro delivers real-time guidance.

What You'll Do:

• Design and implement production-grade Python services with clean architecture and strong engineering discipline
• Architect scalable, distributed systems using Domain-Driven Design (DDD) principles
• Integrate with external SaaS systems (CRMs, dialers, meeting tools, OAuth providers)
• Optimize performance, latency, cost, and reliability of AI-driven systems
• Build and orchestrate LLM-powered agents (planning, reasoning, tool usage, memory)
• Develop internal frameworks to manage: Agent coordination, Tool execution, Memory layers, Event-driven workflows
• Work closely with AI engineers, product, and founders to transform complex sales workflows into autonomous processes
• Use AI coding assistants effectively and experiment with AI-augmented development workflows

What We're Looking For:

• 7+ years of strong backend engineering experience
• Advanced Python expertise (async, typing, architecture patterns, testing)
• Experience designing scalable distributed systems
• Experience with GCP (preferred) or AWS
• Mindset: You're energized by building systems that can reason and take action, not just generate responses
• Fluency in English is required; Spanish is a plus

Tech Stack:

• Backend: Python, FastAPI, Celery, PostgreSQL, uv (package-manager)
• Frontend: NextJS, Tailwind
• DevOps: Google Cloud, Kubernetes

Location: Madrid, Spain (hybrid)