Senior Software Engineer (Front End)

HartleyCo; San Francisco (CA); On-site; USD 140,000 - 180,000; Full time

Job summary

HartleyCo, a YC-backed voice AI company, seeks a frontend engineer to own the configuration and monitoring experiences used by customers. You will build prompt-management, dashboards, analytics, and workflows in React and TypeScript.

Join a small team scaling enterprise-grade software with meaningful equity and cash compensation, and be on-site in Redwood City to directly collaborate with customers and backend engineers.

Qualifications

• 2+ years of 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 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

Frontend development

React

TypeScript

Production software

Customer interaction

Education

Bachelor's degree in CS/CE/EE

Tools

HTML/CSS

REST APIs

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.