Full Stack Engineer, AI systems

About ActAI There are over 5 billion users using basic applications today such email, notes, tasks, calendar and they're not AI-native. Our mission is to build proactive applications for anyone in the world, who are not used to complex prompting. We aim to bring intelligence to conversations, errands, organising and workflows, with minimal to no prompting. Our first application is an agent-first mobile communication app. We believe building applications that users use daily for communication, coordination and collaboration needs will help integrate AI into their lives. The net effect is to eliminate misinformation, achieve low coordination costs, enable high quality tasks and collaboration at scale with minimal or little prompting.  RoleWe are looking for a Full Stack Engineer - AI Systems to build the product layer that turns these capabilities into usable, production-grade workflows. This includes designing how agents operate, fail, recover, and deliver consistent value to users.  FocusBuild end-to-end product features across frontend, backend, and AI integrations Design agent workflows that handle planning, tool use, failure, and recovery across multiple steps. Integrate LLMs, memory, and external tools into systems that behave reliably under real-world conditions Design real-time AI interactions with streaming, partial results, and tight latency constraints Improve system reliability, observability, and fallback mechanisms Collaborate closely with ML, backend, and produc