Principal Software Engineer - Revenue Hub

Revenue Hub is building the backbone for businesses to sell, bill, get paid, and manage revenue inside HubSpot. Our systems handle billions of dollars in transactions, so correctness, clarity, and predictability matter.

We're building a commerce platform where the data model, APIs, and flows are first-class. Reps, admins, and agents all work from the same foundation. The vision is a single, connected revenue flow: Contact to Deal to Quote to Order to Contract to Invoice to Payment to Reconciliation.

When that flow is clean and trusted, revenue context becomes available across the whole business: marketing can attribute spend to real revenue, sales can forecast on actual billing behavior, and service teams can see renewal risk before it's too late.

We're looking for a Principal Software Engineer to help shape the technical future of Revenue Hub. This is a very hands-on role. You'll write code, dive into services, review tough designs, debug messy systems, and directly own the architecture behind CPQ, Billing, Payments, and Revenue OS.

A big part of this role is defining how external developers and AI agents interact with those surfaces safely and predictably.

- Shape the technical roadmap across CPQ, Billing, and Payments with strong, opinionated patterns.

- Define and evolve core domain models so pricing, products, contracts, invoices, and payments behave predictably in the UI, over the API, and inside agent-driven workflows.

- Design the API and platform contracts that let developers, partners, and AI agents extend Revenue Hub without coupling to internals.

- Create frameworks that make the platform easy to extend without adding complexity.

- Write code regularly. Lead design reviews and build high-impact systems end-to-end.

- Own large multi-team initiatives that span CPQ, Billing, and Payments.

- Set patterns for extensibility, contract boundaries, financial correctness, event-driven consistency, and how AI agents safely interact with commerce objects.

- Push for simplicity where the domain wants to get complicated, and consistency where surfaces can drift.

- Influence product strategy across CPQ, Buyer Portal, and Revenue OS.

- Help teams make clear tradeoffs between speed, correctness, compliance, and long-term platform health.

- Drive thoughtful design decisions and guide learnings from incidents and large migrations.

- Help teams align on patterns that reduce complexity and increase reliability.

- Proven experience building and scaling distributed systems with strict correctness requirements.

- Strong instincts for API and platform design. You've built things external teams depend on and know what that responsibility feels like.

- Background working with complex state machines, financial flows, or high-integrity data models.

- Familiarity with agentic systems and what it means for AI to safely act on structured data, not just read it.

- The ability to work horizontally across many teams and get alignment on platform patterns.

- A habit of turning ambiguity into clear plans and working software, and staying hands-on every step of the way.