Staff Software Engineer, Billing

The Role

Comfy lets people build creative workflows that combine open-source models running on our GPUs with paid APIs from model providers. Every run has a cost. Customers need to understand what they’re spending, and we need to charge accurately as models, prices, and products change.

You’ll own the engineering behind that: how we meter usage, collect payments, manage credits and subscriptions, and protect against financial abuse. You’ll make billing dependable for customers and give the team the tools to launch new pricing models with confidence.

Our billing stack uses Go, PostgreSQL, Redis, Temporal, Stripe, and Metronome, alongside Python and Kubernetes across the broader platform. You’ll evolve an existing system, work across service boundaries, and take changes from design through production.

What you’ll do

• Capture usage reliably. Build metering for GPU compute and partner model APIs. Handle delayed events, retries, and partial failures so every billable event is recorded once and attributed to the right workspace.

• Own the payment lifecycle. Improve checkout, subscriptions, credit top-ups, plan and seat changes, prorations, refunds, and failed-payment recovery. Keep Stripe, Metronome, and our application state consistent when events arrive late or systems fail halfway through.

• Reconcile charges, payments, and credits. Build automated checks across usage records, invoices, payments, and credit balances. Detect discrepancies, give operators an audit trail, and recover safely when a payment succeeds but credits never arrive. Own production reliability and turn incidents into lasting improvements.

• Make new pricing easier to ship. Build reusable pricing and entitlement systems for individual creators, teams, and enterprise customers. Make changes safe for existing subscribers as we introduce new models, products, and plans.

• Limit financial abuse. Improve spend controls and detection of suspicious usage, payment fraud, and credit abuse. Work with Support and Finance on disputes and recovery while keeping checkout and legitimate usage smooth.

• Give customers and teammates clear answers. Partner with product and frontend engineers on billing experiences, and build tools that let Support, Sales, and Finance investigate charges and resolve issues safely.

You might be a good fit if you

• Have built and operated billing or payments systems in production, with meaningful ownership of usage metering, credits, or consumption-based pricing.

• Have integrated Stripe directly and worked through subscription changes, invoices, webhooks, and payment failures beyond the happy path.

• Can reason carefully about money across distributed systems: idempotency, concurrent updates, reconciliation, rounding, and recovery after partial failure. You can explain how you found and prevented a real billing error.

• Are a strong backend engineer with experience in relational data modeling and reliable APIs. You can learn our stack and work across services to solve a customer problem.

• Care about the experience behind the numbers. You can explain technical tradeoffs to Finance, Product, and Support and use their feedback to build better systems.

• Take ownership from problem definition through rollout and operation. You use AI development tools effectively and verify their output with the care that systems handling money require.

Bonus if you have

• Worked with Metronome, Orb, or a similar metering platform.

• Built durable workflows with Temporal.

• Billed GPU infrastructure or model APIs, tracked provider costs, or built systems for changing rate cards and per-request margins.

• Built spend limits or defenses against card testing, chargeback abuse, or trial and promotional-credit abuse.

• Improved international checkout, payment-method coverage, or payment authorization rates.

• Used ComfyUI, contributed to open source, or built tools for creative professionals.

About Comfy

Comfy () is the AI creation engine for visual professionals who demand control over every model, every parameter, and every output. The most powerful workflow engine for visual AI.

Unlike tools that hide everything behind a prompt box, Comfy lets you connect models, processing steps, and outputs on a canvas where every decision is visible and every step is inspectable. It gives you the building blocks to create workflows nobody's imagined yet, and share them with everyone.

What started as an open-source project in 2023 now has 4 million users, 60,000+ community-built nodes, and 150,000+ daily downloads. It's used by artists, filmmakers, game studios, designers, researchers, and VFX houses, including teams at OpenAI, Netflix, Amazon Studios, Ubisoft, EA, and Tencent.

We're a small, intense team in San Francisco. Our team comes from Stability AI and Google, and many contributed to the ComfyUI ecosystem long before working here. Low ego, high ownership. We work hard and demand a lot of each other, but we have fun. Everyone here is building something meaningful that will end up being our life's work.

If this mission excites you and you view yourself as top-tier talent, your future latent self is waiting for you at Comfy.

Check out our Github () and blog (). We recently raised $30M at a $500M valuation. The round was led by Craft, with participation from Pace Capital, Chemistry, TruArrow, and others.