Member of Technical Staff, Billing

Comfy•San Francisco, CA

12d•$160,000 - $240,000•Onsite

About The Position

Comfy is seeking a Member of Technical Staff focused on Billing to own the engineering behind their billing systems. This role involves managing how usage is metered, payments are collected, credits and subscriptions are handled, and financial abuse is prevented. The goal is to ensure dependable billing for customers and provide the team with tools to confidently launch new pricing models. The billing stack includes Go, PostgreSQL, Redis, Temporal, Stripe, and Metronome, with Python and Kubernetes used across the platform. The successful candidate will evolve an existing system, work across service boundaries, and manage changes from design through production.

Requirements

Experience building and operating billing or payments systems in production with significant ownership of usage metering, credits, or consumption-based pricing.
Experience integrating Stripe directly, including handling subscription changes, invoices, webhooks, and payment failures beyond the happy path.
Ability to reason carefully about money across distributed systems, including idempotency, concurrent updates, reconciliation, rounding, and recovery after partial failure, with the ability to explain how a real billing error was found and prevented.
Strong backend engineering skills with experience in relational data modeling and reliable APIs.
Ability to learn the existing stack and work across services to solve customer problems.
Care about the user experience behind the numbers and ability to explain technical tradeoffs to Finance, Product, and Support, using their feedback to build better systems.
Ability to take ownership from problem definition through rollout and operation.
Effective use of AI development tools with careful verification of their output for systems handling money.

Nice To Haves

Experience with Metronome, Orb, or similar metering platforms.
Experience building durable workflows with Temporal.
Experience billing GPU infrastructure or model APIs, tracking provider costs, or building systems for changing rate cards and per-request margins.
Experience building spend limits or defenses against card testing, chargeback abuse, or trial and promotional-credit abuse.
Experience improving international checkout, payment-method coverage, or payment authorization rates.
Experience with ComfyUI, contributions to open source, or building tools for creative professionals.

Responsibilities

Capture usage reliably by building metering for GPU compute and partner model APIs, handling delayed events, retries, and partial failures to ensure every billable event is recorded once and attributed correctly.
Own the payment lifecycle, including improving checkout, subscriptions, credit top-ups, plan and seat changes, prorations, refunds, and failed-payment recovery, while maintaining consistency between Stripe, Metronome, and application state.
Reconcile charges, payments, and credits by building automated checks across usage records, invoices, payments, and credit balances, detecting discrepancies, providing audit trails, and recovering safely when payments succeed but credits do not arrive.
Own production reliability and implement lasting improvements based on incident analysis.
Make new pricing easier to ship by building reusable pricing and entitlement systems for various customer types and ensuring changes are safe for existing subscribers.
Limit financial abuse by improving spend controls and detection of suspicious usage, payment fraud, and credit abuse, working with Support and Finance on disputes and recovery.
Provide clear answers to customers and teammates by partnering with product and frontend engineers on billing experiences and building tools for Support, Sales, and Finance to investigate charges and resolve issues.