Software Engineer, Product

Rainfall Ventures; Palo Alto (CA); On-site; USD 150,000 - 230,000; Full time

Benefits offered by this job

Unlimited PTO

401(k) matching

Health, vision and dental benefits

Job summary

Harmonic is seeking a Software Engineer to drive both product architecture and core infrastructure for its flagship engine. You will build robust backend services and deliver polished, high-performance user interfaces, owning systems from inception to launch.

The role requires hands-on experience with TypeScript, Python, and distributed systems, plus a track record of delivering scalable, reliable software in a fast-paced environment. Join an elite technical team backed by prominent investors.

Qualifications

• BS in Computer Science, Engineering or related field or equivalent experience.
• 5+ years building production applications at scale.
• Strong TypeScript/React and Python skills with backend data pipelines.
• Experience designing distributed systems and REST/GraphQL APIs.
• Proven ability to ship user-facing products from concept to launch.

Responsibilities

• Own end-to-end product development, collaborating with Head of Product and design.
• Architect and optimize full-stack components for complex interactive data streams.
• Design, implement, and maintain scalable APIs and data flows.
• Translate technical capabilities into intuitive user interactions.
• Maintain reliable, observable backend systems and cloud infrastructure.
• Support platform integrations and public-facing web systems.

Skills

TypeScript

React

Python

Distributed systems

RESTful APIs

GraphQL APIs

Front-end-backend integration

Software architecture

Performance and reliability

Education

BS in Computer Science or related field

Tools

Cloud infrastructure

Job description

About Harmonic

At Harmonic, we are building a mathematical reasoning engine that operates with absolute precision. While most AI makes maximum-likelihood guesses, Harmonic's Aristotle uses Lean 4 and reinforcement learning to verify its reasoning and results.

Following our Gold Medal-level performance on the 2025 International Math Olympiad (IMO) and the successful resolution of long-standing open problems, we are proving that AI can master the most rigorous domains of human thought. Backed by some of the world’s most prominent investors, we are intentionally scaling an elite technical team.

About the Role

We are seeking a talented Software Engineer to drive both the product architecture and core product infrastructure of Harmonic’s flagship product. In this role, you will be building robust backend services and delivering polished, performant user interfaces. We are looking for a driven self‑starter who wants to own systems from inception, with a proven track record of architecting applications from the ground up, building scalable services, and delivering high-performance, reliable systems.

Key Responsibilities

• Own the end-to-end product development, collaborating with our Head of Product and designer while maintaining high-performance backend infrastructure
• Architect and optimize full-stack components to efficiently process and render complex, interactive data streams
• Design, implement, and maintain scalable APIs and data flow architectures
• Partner closely with design, research, and leadership to translate complex technical capabilities into functional, intuitive, and feature-rich user interactions
• Manage and scale backend systems and cloud infrastructure to ensure reliability and observability
• Architect and maintain the technical infrastructure supporting our core platform integrations and public-facing web systems

Minimum Qualifications

• BS in Computer Science, Engineering, a related field, or equivalent industry experience
• 5+ years of hands‑on relevant industry experience building production applications at scale
• Proficiency with TypeScript, React, or similar modern web technologies, alongside strong proficiency in Python for backend logic and data pipelines
• Deep experience designing distributed systems, RESTful/GraphQL APIs, and integrating frontend components with backend services
• Experience collaborating with design, product, research, and infrastructure teams to ship user‑facing products from concept to launch
• Proven experience authoring clean, performant code for scalable backend architectures
• Experience with modern software development practices including coding standards, code reviews, source control management, build and deployment processes, and testing
• Experience with experimentation and iterative development process
• Proven work ethic, self‑motivation, and a passion for building impactful products
• Proven track record operating successfully in a fast‑paced, collaborative environment

Preferred Qualifications

• Prior experience building high-throughput messaging pipelines or real-time data systems
• Experience with building complex web user applications
• Demonstrated product sense in partnerships with design, product, research, and infrastructure engineers
• Experience as a founder or early engineer building a product from scratch from ideation to launch

What We Offer

• Unlimited PTO
• 401(k) matching
• 100% employer‑paid health, vision, and dental benefits for employees and 50% coverage for dependents. Harmonic offers varied health coverage options to select what is best for you and your family.
• Health Savings Account (HSA) available for qualifying health plans

Equal Opportunity Statement

Harmonic is committed to diversity and inclusivity in the workplace. We are an equal‑opportunity employer and do not discriminate on the basis of race, religion, national origin, gender, sexual orientation, age, veteran status, disability or any other legally protected status.