Software Engineer, Front-End Systems

Stealth AI Startup; San Francisco (CA); Remote; USD 150,000 - 250,000; Full time

Job summary

A pioneering AI startup seeks a frontend systems engineer to innovate their intelligence platform. This foundational role involves crafting adaptive interfaces, maximizing user clarity, and collaborating with diverse teams. The ideal candidate will have deep expertise in modern frontend technologies and contribute to shaping a new frontier in AI interaction.

Benefits

Meaningful equity

Remote-flexible work

Quarterly in-person gatherings

Qualifications

• Deep expertise in React, TypeScript, and modern frontend architectures.
• Experience building production-grade UIs with real-time feedback.
• Ability to design flows and states that remain stable under complexity.

Responsibilities

• Architect and build production-grade UIs with real-time feedback loops.
• Collaborate with teams to align interaction patterns with backend logic.
• Translate evolving model capabilities into structured, intuitive interfaces.

Skills

React

TypeScript

Frontend Architecture

System Design

Tools

Next.js

Vite

Node.js

Tailwind

Job description

Craft the interface of intelligence: fast, structured, and radically adaptive.

About Noumena

Noumena is an AI research lab and product company building toward AGI through narrow, adaptive intelligence. Our systems evolve through use, reflecting and amplifying the judgment of the people who work with them. We own every layer, from infra to interface, so intelligence and interaction can evolve in lockstep.

We’re starting with expert software developers. But the platform we’re building will adapt to experts across fields: engineering, research, operations, and beyond.

About the Role

We’re hiring a frontend systems engineer to shape the public and product-facing surfaces of Noumena’s intelligence platform. This is a foundational role where UI isn’t just presentation; it’s how intelligence becomes legible, learnable, and trusted.

You’ll build adaptive, real-time interfaces that sit directly atop our evolving models and runtime systems. You’ll work across modeling, infrastructure, and product teams to ensure every surface you touch feels coherent, structured, and fast, even as it adapts in real time.

This isn’t frontend-as-polish. It’s frontend as interface logic, crafted for experts who think deeply and move quickly.

Tech Stack

TypeScript, React, Next.js, Tailwind, Node.js. Bonus points for experience across the stack with Python or Rust and with adaptive or model-facing UI architectures.

What You’ll Do

• Architect and build production-grade UIs with real-time feedback loops
• Translate evolving model capabilities into structured, intuitive interfaces
• Lead implementation of developer-facing experiences (docs, onboarding, auth, billing)
• Collaborate with infra and model teams to align interaction patterns with backend logic
• Shape internal tools that support structured planning and engineering workflows

You May Be a Good Fit If You:

• Have deep expertise with React, TypeScript, and modern frontend architectures (e.g., Next.js, Vite)
• Think in systems, not stacks, designing flows and states that remain stable under complexity
• Have built production auth, billing, or IAM flows with performance in mind
• Write maintainable, performant code that improves every system it touches
• Know how to balance clarity and speed across evolving requirements
• Lead through quality, setting standards and mentoring others by example
• Value developer UX, docs, onboarding, and long-term maintainability
• Navigate ambiguity with craft, ownership, and curiosity

Bonus Points For:

• Experience building dev-facing platforms, SDKs, or public APIs
• Familiarity with identity (Clerk, Auth0, NextAuth) and billing systems (Stripe, Metronome, Orb)
• Prototyping or maintaining design systems (Tailwind, Chakra, etc.)
• Building documentation platforms (Storybook, MDX, etc.)
• Optimizing frontend systems for global, low-latency users
• Experience with SEO metadata, structured data, and indexing

Why This Role Matters

This is the surface where deep systems meet real people. It’s the frontend of a frontier: the invitation to trust, to explore, to build. What you ship will shape how Noumena is seen, understood, and used.

You won’t just polish a product. You’ll craft the public intelligence layer of a vertically integrated system, where every pixel, prompt, and pattern is grounded in clarity, coherence, and control.

Team & Culture

We’re a small, senior team of researchers, engineers, and builders. We value deep ownership, curiosity, and deliberate thinking. We care about coherence, from silicon to syntax, and we move with quiet urgency.

We’re remote-flexible and invest in real-world time together, especially during pivotal build phases. We’re radically deliberate: open to experimentation, allergic to drift, and committed to systems that matter.

Location & Compensation

• Remote-flexible (with travel covered for quarterly in-person gatherings)
• Open to candidates spending time in the Bay Area during key build phases
• Base salary: $150,000 – $250,000
• Includes meaningful equity: high-impact work means high ownership