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# Senior Design Engineer

- **Company:** PRODUCTIVE PRODUCTS LLC
- **Location:** Los Angeles, CA, United States
- **Experience:** Expert
- **Salary:** $350,000
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, ARM Architecture, Cascading Style Sheets (CSS), Github, Human-Computer Interaction, Data Streaming, TypeScript, ReactJS, AI Coding Agents, Figma, Front End Software Development
- **Published:** November 9, 2026
- **Apply:** https://www.juju.com/job/28_25304_e6430b03231b9008858a4f0cfdd0a327

## About the Role

We need a senior builder who takes consumer interfaces from design exploration to live production code with zero handoff, and who co-owns the /shop Design Record and design system in code. You are senior: you've shipped interfaces people love, you have a real human-computer interaction background, and your portfolio shows taste a stranger can see immediately. You partner directly with our Founding Designer and the founder to set and raise the consumer design bar across every surface., The craft you must already own: a real human-computer interaction background, not a gloss of design vocabulary; a very strong design eye, proven by a live portfolio of shipped work; building interfaces in React, TypeScript, and CSS at production quality; fluency in Figma; motion physics and state designed on purpose; and AI coding and design tools as force multipliers you verify by hand.

Comparable experience: a senior design engineer or frontend engineer with real design taste and an HCI background, a principal/senior product designer who ships their own production React code, or someone who designed and shipped a consumer product end to end.

Who You Are

How you think. You see a screen as a system: what state it's in, what it's telling the person, and where friction hides. You think about the person on the other side of the screen the way a human-computer interaction education teaches: what they're trying to decide, what they can perceive, and how layout, typography, and motion earn their trust.

How you work. A design tool, a coding agent, and a browser open together, most of the day. You use AI tools as force multipliers for design and code, and you verify every detail because you can build it by hand.

## Description

* The Verification Checker and a conversational surface that shows its work. Whether a shopper pastes a recommendation into the Verification Checker or asks a shopping question in chat, the interface grades claims across five verification states, streams citations, and lets a person inspect the evidence beside the verdict without losing the thread. Streaming state, interruption, and motion physics are design decisions, not plumbing.
 * Decision-shaped interfaces. The unit of every surface here is a verified answer and how sure we are of it. Confidence has to render as credible, never oversold and never buried, and that's motion, state, and typography doing trust work.
 * The /shop Design Record and a design system agents build inside. Master tokens, a canonical component catalog, and usage rules precise enough that coding agents generating a screen stay within the bar.
 * Prototypes that are the real thing. The design-to-engineering handoff is gone here. A direction is explored as a working prototype in a design tool and in production React/TypeScript in the same session, and the winners ship live.
 * Cortex, the shared AI brain the company runs on. You work inside it daily, directing coding agents as force multipliers the way our founder does, and since August any operator here can change the rules the company runs on, live, without waiting on founder approval.

If reading that energizes you, keep going. If it feels overwhelming or underspecified, this isn't the right fit., 1. Async video screen (or Fast-Track Portfolio/GitHub review). About 15 minutes, on your own time, replacing the recruiter screen - or, if you have a standout live portfolio of shipped interactive work and GitHub repos.

 2. Calls with company stakeholders. Short conversations with the people you'd build beside, including our Founding Designer.
 3. Conversation with the founder. How you see a screen, how you use your tools, and what you'd elevate first across the Verification Checker and /shop.
 4. Paid work trial (PRJ-75). A paid real-work trial in our environment: taking a live /shop Verification Checker or consumer interface from direction to shipped production React/CSS inside the /shop Design Record. We look for visual taste, motion physics, how you use AI tools as force multipliers, and how we collaborate together.