Ka'i Kau

Senior Product Engineer

kai@kaikauux.com kaikauux.com linkedin.com/in/kaikau

Senior product engineer with 10+ years of experience building AI systems, product software, spatial computing tools, and enabling infrastructure. Strongest in 0-to-1 environments where product taste and engineering both matter. Recently shipped core technology for an agentic cofounder at a YC company; previously built generative AI product features at Blockade Labs, systems-heavy product work at Fluid XR, and the open-source 360 Panorama Capture tool featured on Google VR developer pages and used by thousands of developers to create images and videos seen billions of times.

Core Strengths

AI and agent systems: Agent harnesses, evals, multi-step workflow orchestration, and systems designed to be operational, reliable, and observable.
Product engineering: End-to-end ownership across UX, frontend, backend, and systems in early-stage startup environments.
Interactive systems: Realtime media, browser, graphics, and input work across Unity, three.js, WebGL, WebRTC, and spatial interaction models.
Technical range: TypeScript, React, Node.js, Python, Java, generative AI workflows, and startup infrastructure.

Experience

Product Engineer, Pre

YC company | 2026

Agentic Cofounder

Shipped core product technology for an agentic cofounder, including the agent harness and eval infrastructure that made the product operational, reliable, and observable.
Built multi-step founder workflows across Gmail, Google Calendar, Linear, GitHub, PostHog, Supabase, Stripe, and other startup systems so the agent could work from real company context.
Enabled workflows such as weekly investor updates and other cross-tool operational tasks where memory, orchestration, and reliable action mattered more than a chat-only experience.

Focus: Agent workflows, eval infrastructure, operational tooling, product engineering

Product Engineer, Fluid XR

2024-2025

AI, media, browser, rendering, and input systems for spatial computing

Built VR Agent Jessica, an embodied AI assistant for VR with low-latency voice, browser actions, and multi-step execution inside an immersive environment, before reasoning models became the default expectation for agent behavior.
Built product systems that made the platform more complete and usable, including SmartTV in XR, WebExtension UX in XR, and Off-Axis Stereo Rendering.
Improved cloud-streamed Xbox game support with Tracked Gamepad Emulation, including inferred 6DOF tracking built from tracked hand positions on devices without fiducial-marker or object-recognition support.
Built creator and environment features including Fluid Camera System for authored XR capture and Generative Skybox Rooms for AI-driven environmental customization.

Technologies: Unity, WebRTC, three.js, WebGL, Java, AI APIs, Android, realtime media, spatial UX

UX Developer, Blockade Labs

Contract | 2023

360 Sketch to Image

Helped ship a production generative tool that turned rough sketches into immersive 360 scenes, moving a promising AI concept into a real product.
Built frontend and UX around the creation loop so users could guide composition and intent rather than rely on prompt-only trial and error.
Worked at the intersection of model capability, product UX, and business viability to make the feature usable for real customers.

Technologies: React, three.js, Stable Diffusion, ControlNet, WebXR

Earlier Experience

Founder and Lead Developer, VRCHIVE / 360 Panorama Capture

2015-2022

Open-source infrastructure for immersive content distribution

Built 360 Panorama Capture, an open-source Unity tool for high-fidelity 360 capture that was featured on Google VR developer pages.
The tool was used by thousands of developers to create images and videos seen billions of times, turning a technically difficult workflow into something broadly accessible.
Built products and supporting infrastructure around immersive content, distribution, and interactive viewing during a formative period for VR.

Technologies: Unity, shaders, WebGL, three.js, open source

Technologies

TypeScript, React, Node.js, Python, Java
API design, product UX, startup product engineering
LLMs, agent workflows, eval systems

Stable Diffusion, ControlNet
Unity, three.js, WebGL, shaders, WebRTC
Android, browser engines, spatial computing

Additional Background

Co-founded two startups
Strongest in ambiguous greenfield product work
Experience with accelerator/incubator environments including Blue Startups, BoostVC, and Founders, Inc.

Self-taught developer with 10+ years building production products and systems
Equivalent practical depth to a computer science degree through shipped systems
UX Design Certificate, University of Washington