Jestaz / OPEN · Q3 2026
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[ 01 ] · INDEX
PORTFOLIO · 2026
NYCEST 2019SENIOR · PRODUCTAI SYSTEMS
[ AVAILABLE · Q3 2026 ] / NYC / PRODUCT DESIGN · AI SYSTEMS

I design the decisions AI products make — not just the screens.

Product designer focused on the line where AI meets real consequences. What the model is allowed to decide. What has to be a rule. How the system shows its work. Currently shipping case studies on multi-agent systems, retrieval memory, and LLM policy architecture.

→ BASED IN New York City · working globally
→ FOCUS AI systems · product · UX architecture
→ LATEST Director · Supply Chain MAS · Apr 2026
→ BACKGROUND 5 yrs · B2B · social · finance · a11y
[ 02 ] · FEATURED WORK
2026 · IN DEPTH
SIX CASE STUDIESMYSTNIGHT · NEWEST5 SHIPPED · 1 BETA
[ 03 ] · FEATURED / 01
2026 · 9 MIN READ · LIVE AT MYSTNIGHT.COM
NEXT.JS · SUPABASELLM GAME MASTERREAL-TIME DUOVOICED · MONETIZED
[ 04 ] · FEATURED / 02
2026 · 11 MIN READ · LIVE ON APP STORE
iOS · SwiftUIAPPLE FOUNDATION MODELS2 AI MOMENTS~80% API SAVINGS
[ 05 ] · FEATURED / 03
2026 · 9 MIN READ
≤ 8s LATENCY0 DEAD-ENDS5-WAY INTENT
[ 06 ] · FEATURED / 04
2026 · 10 MIN READ
F1=0.94180,519 ROWS4 SUB-AGENTS3 ROUTER STRATEGIES
[ 07 ] · FEATURED / 05
2026 · 6 MIN READ
42 CARDS6 CLUSTERSUMAP 2DLOCAL-FIRST
[ 08 ] · FEATURED / 06
2026 · 8 MIN READ
4 GATES6/6 ATTACKS BLOCKED0 HALLUCINATED APPROVALS
[ 09 ] · SELECTED
2019 — 2025
4 PROJECTSE-COMM · AI · A11Y · SOCIAL
02 · SELECTED WORK

Earlier & client work — five years.

The boring, important parts of products — IA, data-heavy dashboards, permission-gated flows, AI-augmented client work.

MystNight AI GAME MASTER · LIVE CASE "It wasn't me — I was in the study." "Then whose knife has blood on it?" 2 PLAYERS · LIVE-GENERATED · VOICED
2026PRODUCT · AI · LIVE
MystNight · AI Game Master

A live web product where an AI hosts a murder mystery for two players — generating a locked case, playing autonomous lying suspects, and grading the accusation. Next.js · Supabase · LLM · TTS · Stripe.

CASE STUDY
MechaPro homepage — Professional Auto Service & Bodywork Equipment
2025CLIENT · E-COMM · LIVE
MechaPro · B2B equipment

A heavy-equipment e-commerce site where a single decision can be $20K. Designed the IA, configurator, trust modules and buyer flows — first 30 days: $38K+ revenue, $9.7K AOV.

CASE STUDY
SAGE TEST PREP New York's Best Learning Center Click here Shirely AI · ONLINE Hi! I'm Shirely. Which program brings you here today? SAT/ACT RESEARCH ~12% CONVERSION · 4× INDUSTRY AVG
2026CLIENT · AI · LIVE
SAGE · AI receptionist

A multi-program NYC learning center site with Shirely — an AI assistant that classifies parent intent, holds boundaries on pricing & promises, and routes to branch staff. ~12% conversion (4× industry avg).

CASE STUDY
A11y Copilot — accessibility scanner UI
2025B2B · AI · A11Y
A11y Copilot

An AI accessibility scanner that explains WCAG violations in plain English and proposes design-level fixes — not just color-contrast tickets.

CASE STUDYSOON
Tomason Movie lover Requests Booked Tony Lets go eat REQUEST $17.52 NYC · 57% LONELY · GATHER
2021SOCIAL · MOBILE
Gather

A mobile app for strangers meeting IRL. Designed around the question: how does a social product create trust between people who haven't met yet?

OVERVIEW
[ 10 ] · ABOUT
JESTAZ YAO · NYC
NYCEST 2019SENIOROPEN · Q3 2026
03 · ABOUT

I design the parts of AI products where the decisions are actually hard.

Five years in product design — moving from B2B SaaS and accessibility tooling to AI-augmented client work (SAGE, MechaPro, A11y Copilot) to multi-agent systems and retrieval architecture (Director, RAG, Translator Pattern). The thread: I'm most useful where the design problem isn't "make this screen prettier" but "decide what the model gets to decide, and what stays a rule."

Born in Beijing, based in NYC. Senior product designer, comfortable in code (TS, Python, swift to wire prototypes), and the person on the team who'll argue for the fallback flow before the happy path.

→ NOWOpen to senior product / AI design roles · NYC or remote.
→ TOOLSFigma · Linear · Cursor · Python · TS · Claude · GPT.
→ FOCUSLLM products · multi-agent systems · retrieval UX · AI policy patterns.
→ INDUSTRIESAI tooling · B2B SaaS · e-commerce · creator finance · social.
/01

Design the failure mode first.

What happens when the model is wrong? What does the user see? Where does the system route to next? I draw the unhappy path before the happy one.

/02

LLM translates. Code decides.

I treat the model as a translator from messy human inputs to typed structured data. The structured data goes through deterministic gates. The model isn't allowed to be the final authority on anything irreversible.

/03

Show the work, not just the answer.

Confidence scores, citations to source rows, retrieval rays, traces. Users trust systems that let them check the work — and design has to make the checking cheap.

/04

Care more about the boring half.

Empty states, error states, permissions, ops dashboards, trust modules. The half that doesn't ship to the demo reel is the half that actually keeps users.

[ 11 ] · CONTACT
OPEN · Q3 2026 · TRANSMITTING
EMAIL · LINKEDIN · RESUMERESPONSE WITHIN 48H
05 · GET IN TOUCH

Building something where the design decisions are actually hard?

AI products, multi-agent systems, retrieval, complex B2B flows — that's the work I want. Drop a note and tell me what you're building.