Senior Product Engineer (AI, Full-Stack)

OpenKrill; United States; On-site; USD 120,000 - 180,000; Full time

Benefits offered by this job

Health insurance

Flexible paid time off

Equity

Fully remote culture

Job summary

AZX, a fast-growing, profitable AI startup, seeks a Product Engineer who owns demos from schema to deployment and observability. You will work across chat surfaces, the app builder, and the platform’s shared components, ensuring enterprise readiness with accessibility, localization, and audit trails.

You’ll collaborate with backend and runtime teams to ship robust features. You’ll need hands-on experience with React/TypeScript, streaming protocols, and full-stack work, including authentication,

Qualifications

• 5+ years of production experience with React/TypeScript and streaming UIs.
• Experience end-to-end with a streaming protocol (SSE or WebSocket).
• Full-stack ownership: backend front end, including auth, idempotency, pagination, race conditions, migrations.
• Enterprise-facing accessibility, localization, and audit trails are required.
• Experience coding agents and AI-native workflows, with tool-assisted outputs.
• Ownership mindset: instrumentation, evals on AI behavior, on-call included in definition of done.

Responsibilities

• Build and evolve chat surface and agent workspaces with streaming protocols.
• Collaborate on the app builder template and toolchain; support preview sandbox, generation loops.
• Maintain design system across chat, workspaces, and app builder for consistency.
• Develop the agent-facing developer experience: CLI, deploy tooling, manifests.
• Own full-stack features: TS frontend, Node/FastAPI BFF, Postgres, deployment, on-call.
• Demonstrate enterprise readiness: accessibility, localization, audit trails; demo-ready.
• Read backend traces and logs to debug across product, backend, and platform teams.

Skills

React/TypeScript

Streaming UIs

Full-stack ownership

AI tooling & coding

Instrumentation & telemetry

On-call duty

WebSocket/SSE

Education

Bachelor's Degree

Master's degree (plus)

Tools

Node/Fastify

Python/FastAPI

PostgreSQL

Redis

OAuth2/OIDC

Job description

About AZX

Our mission is to accelerate positive impact in critical industries through AI transformation. We specialize in physics-informed ML and enterprise AI solutions that directly address climate and sustainability challenges.

We're growing quickly and already work with category-leaders in real estate (CBRE), energy (LevelTen Energy), logistics (Flexe) and utilities.

We bootstrapped profitably for our first year and are now backed by leading investors focused on AI, climate and energy.

We work on challenges in clean energy, decarbonization, climate risk, energy systems, and global economics. We're building our company for long-term success and aim to create the ultimate place to work for those passionate about AI and making a positive impact.

About This Role:

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.

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.

Core Qualifications:

• 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; Master's is a plus

Why AZX!

• Be part of a fast-growing, profitable, mission-driven company with industry-leading clients tackling the massive opportunity of AI transformation in critical industries.


• 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


• Fully remote culture with a cluster of teammates in Seattle

Additional Information:

• Must be able to travel 2x/year for company summits


• Applicants must be currently authorized to work in the United States on a full-time basis.


• We are unable to sponsor or take over sponsorship of employment visas at this time.


• Please only apply to a maximum of 2 roles at a time, any applicants who apply to more than 2 roles within a 6 month period will automatically be disqualified