Principal Software Engineer - Mend AI (AI Security)

We're looking for a Principal Software Engineer to take end-to-end ownership: from research and design through production, on systems that combine classical algorithms with AI/LLM-based capabilities. This is an AI-native role in both senses - you'll build security for AI systems, and you'll work AI-first yourself, using coding agents across the development lifecycle and knowing how to get consistently high-quality results from them.
You'll work as a senior individual contributor with real influence over architecture and product direction, collaborating directly with security researchers, data scientists, and product managers across our Poland and Israel teams (1-hour time difference - genuine daily collaboration, not satellite work).
What You'll Do:
Own solutions end to end - from studying the domain and generating your own ideas, through research and design, to coding, shipping, and supporting them in production.
Drive independent research in a new domain where problems are not fully defined, balancing innovation with practical, cost-effective engineering
Build and evolve backend & frontend, extending traditional microservices with AI/LLM-based capabilities
Use AI agents throughout development - research, design, coding, and testing - to raise both speed and quality
Work closely with security researchers, data scientists, and product managers to turn ideas into shipped product