Backend Engineer (Python)

Shelf is an enterprise company focused on building a unique operating system for an automated future, enabling AI agents to reliably reason and deliver precise outcomes at scale. They serve enterprise customers such as Glovo, Nespresso, and HelloFresh, and their platform follows SOC2 and HIPAA-ready security practices. The company operates product and engineering centers in Warsaw and Lviv, with their headquarters in New York.

• Strong senior-level backend engineering experience in production systems.
• Strong Python skills and ability to design clean, maintainable backend code.
• Good distributed systems judgment covering concurrency, failure handling, data consistency, asynchronous work, and service boundaries.
• Hands-on experience with cloud infrastructure such as AWS, GCP, or Azure.
• Comfort with database schema design and performance tuning for real-time and high throughput scenarios.
• Security-conscious engineering approach to handle enterprise-grade requirements and sensitive data.
• Ability to take ownership from problem statement to design and production rollout.
• Clear written and verbal communication skills to explain systems, trade-offs, and incidents.
• AI-native working style using AI tools in daily engineering workflow to enhance tooling, workflows, and engineering leverage.

Strong Plus:

• Experience building agentic systems such as AI agents, tool-calling, orchestration, or LLM-backed infrastructure in production.
• Working knowledge of TypeScript or ability to contribute across the stack.
• Experience shaping technical direction for other engineers without formal management responsibility.

• Design and ship backend services, APIs, data flows, and background processing for production systems.
• Turn vague requirements into concrete technical plans, trade-offs, and execution.
• Own services after launch, including reliability, observability, performance, and incident response.
• Instrument production systems to use signals for iteration and improvement.
• Make sound decisions around system boundaries, data models, interfaces, and scaling paths.
• Collaborate closely with product, frontend, and platform engineers for end-to-end outcomes.
• Improve engineering leverage through AI tooling, automation, and internal workflows.
• Raise quality standards via code review, design review, and pragmatic technical leadership.

Location – Warsaw, work from the office.