Senior Backend Architect — AI-Driven Web Platform

Callimacus; Milano; On-site; EUR 45,000 - 65,000; Full time

Job summary

Callimacus in Milan is seeking a senior backend engineer to shape the platform as production scales. You will own the architecture, design core backend services, and guide API design for multi-modal AI workflows.

You will optimize performance, lead reliability improvements across AWS infrastructure (ECS, RDS, S3, ALB), and shape data models across Aurora/ClickHouse for scalable analytics. Join a small, founder-led team with high ownership and growth opportunities.

Qualifications

• Strong TypeScript and Node.js — async, concurrency, API design.
• Experience with AWS architecture and infrastructure as code.
• Experience with relational and analytical stores (Aurora, ClickHouse).
• Familiarity with event-driven architectures and streaming systems.
• Observability, incident practice, and post-mortems.
• Focus on performance and cost optimization; security and reliability engineering.

Responsibilities

• Set the architectural direction for core backend services and APIs powering multimodal AI workflows.
• Own performance end-to-end across services, databases, and infrastructure.
• Architect the cloud footprint on AWS with security and cost efficiency in mind.
• Design the data layer across Aurora/ClickHouse and data pipelines.
• Raise the reliability bar with monitoring, alerting, and incident response.

Skills

TypeScript

Node.js

AWS architecture

Observability

Performance optimization

Reliability engineering

Security engineering

Tools

Docker

AWS

CI/CD

Job description

Callimacus in Milan is seeking a senior backend engineer to shape the platform as production scales. You will own the architecture, design core backend services, and guide API design for multi-modal AI workflows.

You will optimize performance, lead reliability improvements across AWS infrastructure (ECS, RDS, S3, ALB), and shape data models across Aurora/ClickHouse for scalable analytics. Join a small, founder-led team with high ownership and growth opportunities.