OSS · In progress
stream-ui.
React component library for streaming AI agent output — token rendering, tool-call cards, human-in-the-loop primitives. Building in public.
ReactTypeScriptTailwindSSE
Coming soonAvailable · Selectively interviewing
I'm Ulises — Staff Product Engineer. Building real-time, Web3 and AI-native products, and the systems behind them.
Recent work at Ava Labs on Core Wallet — WebSocket state architecture, on-chain RPC integrations, design system. Prior at Unity, PayPal, and Resideo (Honeywell). I care about latency, design systems, and the seam between humans and AI agents.
§ 01 / Selected Work
A decade of building at scale.
01Ava Labs / Core WebWallet, Swap, Bridge — real-time DeFi UI under live trading load. WebSocket pricing, Zustand state, Blockaid security integration.2024 — 2026
02Unity TechnologiesLed migration of fragmented web platforms to Next.js + TypeScript. Org-wide design system across multiple high-traffic web properties.2022 — 2024
03Resideo / HoneywellShipped multiple connected-product web apps. Built a Radix + Tailwind design system. Defined frontend testing strategy.2019 — 2022
04PayPalMigrated legacy Backbone product pages to React + TypeScript. Built internal developer tooling. Performance and accessibility focus.2017 — 2019
05RackspaceCloud management tooling for infrastructure teams. React + Redux frontend, Python (Flask, Celery) backend.2016 — 2017
§ 02 / Projects
Things I build on the side.
OSS · In progress
tx-lens.
EVM transaction decoder with ABI inference and call-tree visualization. For when block explorers don't go deep enough.
TypeScriptviemD3
Coming soon§ 03 / About
A short, honest introduction.
I've been writing code on the web since 2010. Over the last decade that's meant shipping product at PayPal, modernizing Unity's web ecosystem, designing component libraries at Resideo (Honeywell), and most recently building real-time wallet experiences at Ava Labs.
The work I'm proudest of usually lives at the intersection of latency, state, and trust — UIs where the user is technical, the data is live, and getting it wrong has real consequences. That framing applies equally well to trading interfaces, agent collaboration surfaces, and engineering tools.
Outside of full-time work I build and ship products of my own. I write technical notes occasionally, contribute to OSS, and tinker with agent-driven workflows.
“Real-time, high-stakes, technical-user UI is the same problem whether you're looking at a trade ticket, a swap quote, or an AI agent's design proposal — get the state model right and everything else follows.” — On craft, 2026