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Senior Product Engineer, Front End

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Flux

Fintech

Senior Product Engineer, Front End

San Francisco Office
On-site
Full-time
Posted Dec 18, 2025
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Opens the original job posting

Software Engineering
On-site

Why Flux

Flux is taking the hard out of hardware, by developing the first AI Hardware Engineer. Our goal is to democratize the ability to create bleeding edge hardware, and revolutionize how electronics are designed and built around the world.

The Role

We’re hiring a Product Engineer, Frontend to shape the core web experience of Flux.

You will work across our browser-based editor, collaboration systems, and AI-powered workflows. This is a high-ownership product engineering role focused on building and evolving complex, interactive interfaces used for real engineering work.

You’ll spend most of your time in React and TypeScript, partnering closely with design and ECAD engineers to keep a sophisticated, real-time application fast, intuitive, and maintainable.

We are open to mid-level through senior candidates. Level, scope, and compensation will align to demonstrated experience, ownership, and the complexity of problems you can independently drive.

Responsibilities

  • Build and evolve core user-facing features in the Flux web app using React and TypeScript.

  • Partner with design to refine flows and interactions from early concepts through production.

  • Maintain predictable and scalable UI state and data flows within a collaborative, multi-pane editor environment.

  • Improve responsiveness and perceived performance as projects increase in size and complexity.

  • Integrate frontend systems with APIs and backend services; collaborate on backend changes when needed.

  • Maintain and evolve shared component libraries and design system primitives.

  • Add and maintain instrumentation for owned features (usage metrics, error logging, UX dashboards).

  • Participate in code reviews, design discussions, and lightweight documentation.

  • Mentor other engineers on frontend best practices where appropriate.

Required Qualifications

  • Strong command of modern React and TypeScript in sizable production codebases.

  • Experience shipping and iterating on complex, interactive web applications (e.g., design tools, visual editors, multi-pane interfaces).

  • Experience building responsive UIs on top of asynchronous or computation-heavy backend systems.

  • Strong product judgment and experience collaborating closely with design and product.

  • Experience with browser performance profiling and debugging.

  • Comfortable working across the stack to integrate APIs and make small backend changes.

  • Experience in startup or high-ownership environments.

  • Based in the San Francisco Bay Area or willing to relocate.

Preferred Qualifications

  • Experience building distributed, collaborative, real-time applications.

  • Experience with complex editor interfaces, CAD, developer tools, or design tools.

  • Familiarity with state management patterns in large React applications (Redux or equivalent).

  • Experience with WebWorkers, WebAssembly, or background computation in the browser.

  • Experience integrating AI-powered features into user-facing products.

  • Experience building high-performance frontends handling large data models.

  • Open source contributions in frontend or developer tooling.

Profile

  • Impact-oriented – You care about real user value, not just shipped code.

  • Comfortable with ambiguity – You thrive in evolving problem spaces.

  • Collaborative – You share ideas early and welcome debate.

  • Experiment-driven – You question conventions and embrace AI-native workflows.

  • Ownership mentality – You bias toward action and take responsibility for outcomes.

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Flux logo

Flux

Company profile

Flux is building the payment network for alternative payments in…

View Flux

Headquarters

Mexico City, CDMX, Mexico

Team size

1-10

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