Senior Product Software Engineer

Location: New York, NY (Flatiron)

Work Model: Onsite, five days a week

Industry: HR technology / payroll / B2B SaaS

Compensation: $195K-$245K base + equity

About the Company

Our partner is an AI-native HR and payroll platform built for founders and startups, with a sweet spot of companies up to about 250 employees. They have grown more than 7x this year, serve over 1,000 customers, and have scaled to roughly 70 employees as they head toward their Series B. Their product thesis is agentic HR: software where agents take on the tedious work so employees and operators don't have to.

The Opportunity

The engineering team is fewer than ten people, completely flat, and reports directly to the CTO, who was the team's first engineering hire. No engineer has left since the company was founded. Everyone in the Product Software Engineer role shares the same scope regardless of level: heads-down backend and infrastructure work on core product capabilities, full-stack product building, and occasional direct conversations with customers to scope what gets built next.

They are looking for senior engineers who have built zero-to-one at startups and can operate with real autonomy. Promotions and compensation reviews are based on performance rather than tenure, with equity adjusted at promotion, and as the team grows there will be room to go deep on specialties such as payments and money movement, authentication and security, or core HRIS features.

Responsibilities

Design and build core product features end to end, from backend services to user-facing surfaces

Build backend infrastructure for new capabilities, including payroll, payments, and money movement

Work with product operations and customers to scope and prioritize features

Participate in a rotating on-call schedule (roughly one weekend every five weeks) supporting payroll-critical systems

Collaborate closely within a small, high-trust engineering team where everyone knows what everyone else is building

Use modern AI tooling to move quickly while maintaining quality

Requirements

4+ years of software engineering experience, including meaningful time at a startup

Strong backend engineering background

A track record of building products or features from zero to one with minimal hand-holding

Comfort with ambiguity and a fast-paced environment

Strong computer science fundamentals

Able to work onsite in New York City five days a week

Experience with TypeScript, React, Next.js, Effect, or AWS, or with payments, HRIS, or authentication and security, is an advantage