Senior Backend Engineer — AI-Native Systems (Warsaw)

Shelf; Warszawa; On-site; PLN 180,000 - 260,000; Full time

Job summary

Shelf is hiring for a Middle/Senior backend engineer to design and own business-critical systems in Warsaw. You will ship production-grade backend services, APIs, and data flows with a focus on reliability, scalability, and clear ownership.

Expect a highly technical environment where engineers shape architecture and drive tangible outcomes. The role emphasizes strong Python skills, distributed systems thinking, and an AI-native approach to tooling and workflows.

Qualifications

• Proven backend engineering experience in production systems.
• Strong Python skills and clean backend design.
• Experience with distributed systems and concurrency.
• Hands-on cloud infra: AWS, GCP, or Azure.
• Database schema design and performance tuning.
• Security-conscious engineering for enterprise data.
• Ability to own design to production rollout.
• Clear written and verbal communication.

Responsibilities

• Build backend services, APIs, data flows for production systems.
• Turn vague requirements into concrete technical plans.
• Own services after launch: reliability, observability, incident response.
• Instrument everything with metrics and traces for iteration.
• Design sound system boundaries and data models.
• Collaborate with product, frontend, and platform teams.
• Improve engineering leverage with AI tooling and workflows.

Skills

Backend engineering

Python

Distributed systems

Cloud infrastructure

Databases

Security

Ownership

Communication

AI-native workflows

Job description

Shelf is hiring for a Middle/Senior backend engineer to design and own business-critical systems in Warsaw. You will ship production-grade backend services, APIs, and data flows with a focus on reliability, scalability, and clear ownership.

Expect a highly technical environment where engineers shape architecture and drive tangible outcomes. The role emphasizes strong Python skills, distributed systems thinking, and an AI-native approach to tooling and workflows.