Perplexity is seeking a Software Engineer to own and evolve the billing platform that powers monetization across all Perplexity products. You'll build the abstractions and infrastructure that let product teams launch new paid offerings, run pricing experiments, and convert users into paying customers — without needing to understand billing internals. This is a high-leverage role on a small team. The usage-based billing system this team owns is the foundation that monetizes Perplexity Computer and our agentic products — metering every action an AI agent takes in real time, enforcing credit budgets, and settling costs across entirely new interaction models. You'll work across subscriptions, usage-based billing, and enterprise contracts to ensure every revenue path is reliable, observable, and easy to extend. Tech Stack: Python | Go | Stripe | PostgreSQL | AWS | Docker RESPONSIBILITIES - Design and maintain billing API abstractions that enable product teams to ship new SKUs, pricing models, and monetization experiments with minimal friction - Build and operate the subscription, invoicing, and usage-based billing systems that serve millions of users across consumer and enterprise plans - Establish reliability standards for billing — tiered SLOs organized by customer impact, proactive monitoring, and alerting to catch revenue-affecting issues before customers do - Partner with Finance, Data Science, Growth, and Security teams to ensure billing data is accurate, auditable, and compliant - Expand payment method coverage and optimize authorization rates to improve conversion globally - Build internal tooling that empowers Support and Finance teams to diagnose and resolve billing issues quickly - Collaborate with security and privacy teams to build secure, compliant checkout and payment flows QUALIFICATIONS - 4+ years of industry experience in software engineering - Direct experience building or scaling billing, payments, subscription, or monetization systems - Deep familiarity with payment processors (Stripe, Square, etc) — including subscriptions, invoicing, disputes, refunds, and webhooks - Demonstrated experience of and appetite for building in-house billing solutions that rival leading best-in-class buy options - Strong backend engineering skills in Python with the ability to reason about complex distributed systems - Experience working with relational databases (PostgreSQL) and making data-informed decisions to prioritize work - Self-motivated with strong ownership instincts — you ship major features ahead of schedule or add feature improvements without asking for permission - Track record of cross-functional collaboration with Finance, Support, or Growth stakeholders NICE TO HAVES - 2+ years of hands-on experience with the Stripe APIs and SDKs - Experience with usage-based or metered billing models - Experience with Apple and Google Play in-app purchase billing - Familiarity with growth experimentation and PLG/self-serve SaaS monetization - Experience building platform constructs that support pricing experiments and A/B testing - Full-stack experience (our frontend is Next.js/React/TypeScript) - Experience in a regulatory or compliance-heavy billing environment Compensation: $220K - $405K