Backend Developer – AI Team

Description

ONE ZERO is Israel’s fully digital, branchless private bank—created to bring private-banking level service to a broader public through advanced technology, automation, and AI.

Building on this mission, we’re developing multiple versions of Ella—GenAI-powered banking copilots tailored to different needs and use cases—to make money management simpler, smarter, and more proactive, delivering personalized financial insights while maintaining the trust, safety, and reliability expected from a regulated bank.

Ella (Tech): Production-grade, AI-powered banking platforms built around multiple types of agentic workflows, LLMs, real-time financial data capabilities, and integrations with core banking systems. Their architecture combines stateful orchestration, intelligent tools, retrieval systems, and secure APIs to deliver personalized banking experiences at scale across different Ella versions.

Why join: A rare opportunity to build real-world business-to-customer AI products used by customers every day. You'll work at the intersection of modern software engineering and Generative AI, solving challenging problems in scalability, latency, reliability, and AI-driven product development.

Your Day-to-Day

• Design, develop, and maintain scalable AI agents serving One Zero customers.
• Build and integrate AI-powered capabilities, LLM-based tools, and agentic workflows into production systems.
• Apply prompt engineering techniques to develop, optimize, and improve LLM-powered features.
• Leverage AI coding tools throughout the software development lifecycle, from design and implementation to testing, debugging, and refactoring.
• Design, build and maintainable reliable and well-tested services that integrate APIs, databases, data pipelines, and cloud platforms to support scalable, secure, high-performance, data-driven AI applications.
• Collaborate with AI Engineers, AI Ops, Product, and other R&D teams to translate complex requirements into production-ready solutions.
• Continuously explore and adopt new AI technologies, frameworks, and development practices.

Requirements

• 3+ years of hands-on experience in backend software development and building production-grade applications – a must.
• Strong proficiency in Python, including clean code, software architecture, and API development – a must.
• Practical experience with LLM APIs and prompt engineering, including integrating Generative AI capabilities into applications.
• AI-native development mindset: hands-on experience using AI-assisted development tools (such as Cursor, Claude Code, or Codex) across the software development lifecycle, while maintaining high engineering standards.
• Strong debugging, troubleshooting and problem-solving skills. Ownership and ability to independently deliver end-to-end technical solutions.
• Experience with relational databases, NoSQL, and analytics data platforms.

Advantages

• Experience with agentic AI frameworks such as LangGraph, LangChain, or other agents platforms.
• B.Sc. in Computer Science, Software Engineering, or a related technical field.
• Familiarity with AI evaluation, observability, monitoring, and performance optimization.
• Experience developing and deploying B2C LLM-powered applications in production, including RAG, tool calling, text 2 query and structured outputs.
• Experience as data science or Machine learning engineer.
• Experience working in fintech, banking, or other regulated environments.