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Engineer — Product & User Interface Systems

San Francisco, US on-site full time senior Feb 13, 2026

About this role

We're building the control plane for AI agents in teams and companies. As a Founding Engineer focused on Product & User Interface Systems, you will design and build the user-facing layer of that control plane — the web applications, workflows, and interfaces that make powerful agent infrastructure usable by real teams. This is not a “frontend-only” role. You will work across the stack: distributed cloud-based systems, Kubernetes-based services, and modern web applications. You’ll collaborate deeply with product and design to turn complex infrastructure into intuitive, high-leverage user experiences. You’ll also help define a new interface paradigm: agents as an interactive modality — not just chat, but structured, controllable, and production-grade workflows. If you care about product quality, system coherence, and shaping how humans interact with autonomous systems — we want to talk. WHAT YOU’LL OWN You will build and evolve the user-facing layer of our platform: WEB APPLICATION & PRODUCT EXPERIENCE - Design and implement React + TypeScript web applications - Build high-performance, stateful interfaces for managing agents - Develop dashboards, policy configuration UIs, audit views, and workflow builders - Create systems that make complex agent behavior understandable and controllable FULL-STACK ENGINEERING - Build backend services supporting the UI - Design APIs for agent control, policy configuration, and observability - Work within a Kubernetes-native, cloud-based distributed system - Collaborate on schema design, data modeling, and service boundaries AGENT-NATIVE INTERFACES - Explore agents as a new user interface modality - Design structured, interactive agent workflows beyond simple chat - Combine UI controls with agent reasoning - Experiment with hybrid patterns: visual + conversational + automated systems CLI & FUTURE INTERFACES - Contribute to a TypeScript- or Python-based CLI - Design consistent interaction patterns across web and CLI - Lay groundwork for potential future mobile interfaces PRODUCT & DESIGN COLLABORATION - Work closely with product and design to translate concepts into shipped software - Participate in usability thinking and iterative refinement - Ship quickly, iterate based on feedback, and improve continuously WHAT WE’RE LOOKING FOR - Experience building production-grade web applications in React + TypeScript - Comfort working across the full-stack of distributed systems - Strong API design instincts - Experience shipping SaaS products used by technical teams - Ability to translate complex backend systems into usable interfaces - Strong product intuition and UX sensibility BONUS - Experience building developer tools or control-plane software - Experience designing workflow builders or configuration-heavy interfaces - Experience with real-time systems or streaming UIs - Experience building CLIs - Familiarity with LLM-powered products or agent systems WHAT MAKES THIS ROLE UNIQUE - You’ll help define how teams interact with autonomous agents. - You’ll build interfaces for infrastructure-level systems. - You’ll operate at the intersection of product design, distributed systems, and AI. - You’ll have ownership from concept to production. This is a high-impact, high-autonomy role. You’ll influence product direction and user experience at the foundational stage of the company. WHO THRIVES HERE - Engineers who care about product polish and system clarity. - Builders who like working across frontend and backend. - People comfortable turning complexity into usable abstractions. - Those excited about inventing new human–AI interaction models.
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