Senior Software Engineer (Front End)

HartleyCo; San Francisco (CA); On-site; USD 120,000 - 180,000; Full time

Job summary

HartleyCo, a YC-backed voice AI company, is building the frontend used to configure, monitor, and improve AI agents for enterprise-scale applications in Redwood City.

The role focuses on owning frontend projects end-to-end, primarily using React and TypeScript, and collaborating with backend and infrastructure teams. You will address production issues and translate customer friction into durable product improvements.

Qualifications

• 2+ years building production software.
• 2+ years of production React and TypeScript experience.
• Experience in a venture-backed product company.
• Evidence of owning substantial product work, not only implementing isolated components.
• Strong communication and a willingness to work directly with customers.
• Availability to work on-site in Redwood City.

Responsibilities

• Build prompt-management, dashboard, analytics, and operational workflows.
• Own frontend projects from architecture through launch.
• Work primarily in React and TypeScript.
• Collaborate closely with backend and infrastructure engineers.
• Debug real production issues with customers.
• Turn recurring customer friction into durable product improvements.
• Influence frontend architecture while the engineering team is still small.

Skills

Production software

Customer communication

Ownership of product work

Venture-backed experience

Education

Bachelor’s degree in CS/CE/EE or related

Tools

React

TypeScript

Job description

A 50-person, YC-backed voice AI company is building the operating platform for AI-powered contact centres.

The company reports growth from $5M to $80M ARR since the beginning of 2025. Its technology is already being used by major enterprises across healthcare, travel, technology, and logistics.

This role owns the frontend customers use to configure, monitor, and improve AI agents.

You will:

• Build prompt-management, dashboard, analytics, and operational workflows
• Own frontend projects from architecture through launch
• Work primarily in React and TypeScript
• Collaborate closely with backend and infrastructure engineers
• Debug real production issues with customers
• Turn recurring customer friction into durable product improvements
• Influence frontend architecture while the engineering team is still small

You should have:

• 2+ years building production software
• 2+ years of production React and TypeScript experience
• Experience in a venture-backed product company
• A US bachelor’s degree in CS, CE, EE, or a related technical discipline
• Evidence of owning substantial product work, not only implementing isolated components
• Strong communication and a willingness to work directly with customers
• Availability to work on-site in Redwood City

This will suit an engineer who wants visible ownership, strong cash compensation, meaningful equity, and direct exposure to a product operating at real enterprise scale.