Hark

Frontend Engineer

Hark
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10 days ago
San Jose, CA, USASenior

Base Salary

$170k - $400k/yr

Responsibilities

  • Build and own frontend surfaces for web, mobile web, and shared component systems.
  • Create UI for real-time streaming agent interactions, including partial responses, mid-stream tool invocations, and out-of-order state updates.
  • Partner with designers to create fast, responsive, polished, accessible, and trustworthy interfaces.
  • Build performant components that scale across product surfaces.
  • Instrument frontend work, track performance, identify regressions, and improve based on real usage data.
  • Collaborate with platform engineers on APIs and data contracts connecting the frontend to the agent runtime.

Requirements

  • Deep frontend expertise with modern React or equivalent, state management patterns, and high-performance interfaces.
  • Experience building real-time interfaces using streaming data, WebSockets, and optimistic updates.
  • Strong product polish and attention to animation, loading states, responsiveness, and usability.
  • Experience shipping consumer products used and depended on by real people.
  • Curiosity about AI and agent products, including experience using LLM-powered products.
  • Ability to work through ambiguity, iterate quickly, prototype, gather feedback, and converge on solutions.
  • Strong communication and collaboration skills with designers and backend engineers.
  • At least 5 years of frontend engineering experience.
  • Experience at a fast-growing AI or consumer product company is preferred.
  • Bonus experience includes voice interfaces, multimodal interactions, mobile development, and animation or motion design systems.

Benefits

  • Full-time position based in the United States.
  • US base salary range of $170,000–$400,000 annually; total compensation may include additional components and benefits.

Tech Stack

Categories

Hark

About Hark

1-10 employees
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