Quanta

Senior Product Engineer

San Francisco, CA · Senior

Sponsorship not specified$205k-$265kDetected 146 days ago

Full-Stack DevelopmentAPI DevelopmentAgentic AIDesign SystemsAccountingCollaborationPlain Language

About the role

We can do in seconds what takes our competitors weeks, which is why we're trusted by many of today's fastest growing startups.
By rebuilding accounting from the ground up, we enable business decisions to be made with timely, complete, and explainable financial information.
Many of today's fastest-growing startups, including Decagon, Braintrust, Browserbase, and Mintlify, rely on Quanta as their financial foundation.

You will solve these problems first for our own team, validate them in real workflows, and then turn the right solutions into product capabilities that scale across the entire customer base.
You will design modular systems that make customization possible without sacrificing stability. Accounting workflows vary by company, and our platform must support those differences while enforcing clear guardrails around data integrity and system behavior.
You will build and evolve the core infrastructure that runs Quanta's accounting and finance platform in production, including ledgers, reconciliation pipelines, and automation workflows.
Accounting reflects how a company operates, but that reality is messy and full of exceptions, and few abstractions work across companies without careful design.
You will design modular systems that make customization possible without sacrificing stability.
Accounting workflows vary by company, and our platform must support those differences while enforcing clear guardrails around data integrity and system behavior.
You will work alongside other engineers to explore how new tools, workflows, and agentic systems can change how we design, implement, and maintain our product.

6-7+ years of full-stack engineering experience, ideally on small, high-impact B2B teams
Comfort with ambiguity, ownership, and self-direction
You are excited about working in person with a collaborative team in San Francisco.
You are uncomfortable working in a complex, judgment-heavy domain where correctness depends on context, not just code.
You have deep familiarity with Quanta's core systems and are comfortable working where correctness is most critical.
You have shaped at least one core abstraction that increases flexibility without compromising trust.
You are a go-to collaborator for engineers and accountants, translating real-world finance problems into clear technical approaches.
You have helped define how the team uses AI in practice to increase leverage.

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We are a tight-knit team of 17, working 4 days in-person in downtown San Francisco.
Our backgrounds sit at the intersection of finance and engineering.
As a group, we have built accounting systems at Affirm, ledgers at Stripe and Robinhood, and companies from the ground up.
We have passed CPA exams, built finance teams from one to dozens, shipped 0→1 products, and scaled systems that support billions in transactions.
We understand our customers because we have been in their shoes.
We care deeply about correctness, trust, and building systems that last.
We are opinionated about the future of finance and committed to building it together.
We are defining the Operational Ledger, a new financial foundation for how businesses truly understand themselves.
If you want to work on deep, consequential systems, financial data is one of the hardest places to do it well.
Accounting sits at the center of every business, yet today it is slow, opaque, and stripped of the context needed to answer real questions.
We use accounting as the raw material, not the end goal.
By operating directly on real customer data and real workflows, we turn messy, judgment-heavy financial data into a reliable, queryable system of record.
We are building the Operational Ledger by staying unusually close to the real work.

This listing is sourced directly from Quanta's careers page and normalized into a canonical job model.