Senior Backend & Platform Architect at Aircall

Aircall is a unicorn, AI-powered customer communications platform used by 22,000+ companies worldwide. We're redefining customer communications by bringing voice, SMS, WhatsApp, and AI together into one seamless workspace.

We are launching a specialized New Product Unit to build the future of autonomous sales. We are improving the AI Orchestration Layer — a system that records and understands every customer interaction (calls, video, email, WhatsApp) to autonomously execute sales workflows: CRM updates, follow-ups, task creation, and coaching insights. Our long-term vision is to evolve this into a self-improving, agentic Sales OS — where specialized AI agents collaborate, coordinate, and continuously optimize the revenue process.

The Role: We are looking for a Senior Backend & Platform Engineer as our 'Founding Platform Engineer.' 50% Infrastructure/Platform and 50% Backend Development.

What You'll Do:

Infrastructure as Code: Design cloud architecture on GCP using Terraform

Kubernetes: Own K8s clusters for heavy AI workloads

Observability: Design strategy using Datadog

Backend Engineering: Design production-grade Python services using Clean Architecture and DDD

AI Orchestration: Build and orchestrate LLM-powered agents (planning, reasoning, tool usage, memory)

AI-Augmented Workflows: Use AI coding assistants effectively

Requirements:

5+ years Backend Engineering

Advanced Python (async, typing, architecture patterns)

Cloud & DevOps: GCP, Terraform, Kubernetes

System Architect: Designing scalable distributed systems

Stack: Python, FastAPI, Celery, PostgreSQL, uv, NextJS, Tailwind, GCP, Kubernetes, Terraform, Datadog.

Location: Madrid, Spain (onsite).