Senior Product Engineer (AI, Full-Stack)

AZX • Seattle, WA

20h • $140,000 - $225,000 • Remote

About The Position

We are seeking a Product Engineer that owns the demos we build for clients from the schema to the pixel, the deployment and the observability. You'll work across the chat surface and agent workspaces, the app builder alongside the platform team, and the shared component and design system, plus the agent-facing developer experience — since our platform's users are coding agents as much as humans. Enterprise readiness is a feature here, not an afterthought: accessibility, localization, and audit trails get demoed, not promised. You'll build on the backend team's services and the runtime team's infrastructure, so overlap down the stack is expected.

Requirements

• 5+ years of deep, production experience with React/TypeScript — streaming UIs, high-frequency updates, virtualization, and real state management, with informed, hands-on opinions about React 19.
• Hands-on experience with a streaming protocol end to end (SSE or WebSocket) — chunk boundaries, reconnection semantics, abort propagation — including having personally debugged a raw byte stream.
• True full-stack ownership: you've shipped the backend half of your own front ends (Node/Fastify or Python/FastAPI), handling auth, idempotency, pagination, race conditions, and migrations.
• Product taste backed by enterprise experience — accessibility you can defend to a screen-reader user, thoughtful empty/error states, and localization that goes beyond a strings file.
• An AI-native working style: daily use of AI coding tools, driven by specs rather than vibes, with concrete examples of where you overrode a tool's output.
• A strong sense of ownership — instrumentation, evals on AI-dependent behavior, cost awareness, and on-call are part of "done," not a later phase.
• Practical depth in some of our core stack — TypeScript (strict), React 19, TanStack Query, Vite, Node/Fastify or Python/FastAPI, Postgres/Redis, and SSE/WebSocket streaming — with a track record of researching into unfamiliar parts of it.
• Familiarity with the surrounding toolchain: zod-validated wire contracts, sandboxed iframes/CSP/postMessage, Playwright/Vitest, WCAG 2.2 AA, i18n frameworks, and OIDC/OAuth2 session mechanics
• Bachelor's Degree

Nice To Haves

• Master's is a plus

Responsibilities

• Build and evolve the chat surface and agent workspaces — streaming protocol on both client and server, message/run persistence, tool-call and approval UX, and citation rendering.
• Partner with the platform team on the app builder: the fixed app template and toolchain it generates against, the preview sandbox seam, and the generation/repair loop UX.
• Maintain the component and design system across chat, workspaces, and the app builder, keeping all three visually and behaviorally consistent.
• Build the agent-facing developer experience — CLI, deploy tooling, manifests — treating coding agents as first-class platform users alongside humans.
• Own the full stack behind your own features: TypeScript front end, Node/FastAPI backend-for-frontend, Postgres schema, deployment, and on-call.
• Ship enterprise readiness as a first-class feature — accessibility, localization, and audit trails — demoed working, not described as roadmap.
• Work down the stack when it matters: read backend service traces and runtime/Kubernetes logs to debug across the seam between product, backend, and platform teams.

Benefits

• Competitive early-stage startup compensation (based on capabilities, experience, and location)
• Bonus eligibility
• Health insurance with meaningful coverage for dependents
• Flexible paid time off
• Equity

What This Job Offers

• Job Type: Full-time
• Career Level: Senior