Backend Engineer, MarketplaceLocation: San Francisco or New York City Company Stage: Late-Stage / Series C AI Infrastructure Company Office Type: On-site Salary: $130K–$400K + EquityCompany DescriptionWe're representing a rapidly scaling AI infrastructure company building the marketplace and operational systems powering the next generation of AI development. Their platform connects enterprises and frontier AI organizations with highly specialized global talent networks that support model training, evaluation, and human-in-the-loop AI systems.The company operates at massive scale, facilitating millions of dollars in expert-driven AI work daily while building the infrastructure layer that enables AI organizations to manage talent, workflows, and operational intelligence. Backed by leading investors and experiencing hypergrowth, they are expanding their core engineering organization across marketplace infrastructure, AI systems, and platform reliability.What You Will DoBuild and scale backend systems that power marketplace matching, routing, allocation, and fulfillment workflowsDesign APIs and infrastructure for search, eligibility, scoring, onboarding, and candidate-job matching systemsDevelop reliable, high-throughput backend services supporting real-time and asynchronous marketplace decisioningArchitect operational tooling and workflow infrastructure that improves reliability, observability, and scalability across core marketplace systemsCollaborate closely with product, ML, and operations teams to translate marketplace requirements into durable technical systemsImprove system performance, latency, throughput, and reliability across production-critical APIs and distributed servicesDesign backend abstractions and infrastructure that allow rapid iteration without compromising system qualityContribute to distributed systems architecture, event-driven workflows, and operational excellence initiativesIdeal BackgroundStrong experience building and operating production-grade backend systems at scaleDeep understanding of system design, distributed systems, performance optimization, and data modelingExperience working on high-throughput APIs, asynchronous workflows, or event-driven architecturesStrong backend engineering fundamentals with proficiency in modern backend languages and infrastructure toolingAbility to balance product velocity with long-term reliability and maintainabilityExperience translating operational or marketplace requirements into scalable technical systemsHigh ownership mindset with strong engineering judgment and pragmatic decision-making abilitiesPreferredExperience building marketplace, matching, recommendation, scheduling, or search systemsFamiliarity with ML-powered products or production model inference systemsExperience with Kafka, Redis, Elasticsearch, or similar distributed infrastructure technologiesExposure to event-driven systems, caching strategies, queues, and observability toolingExperience operating within fast-moving, high-growth engineering organizationsCompensation and BenefitsBase salary: $130K–$400KMeaningful equity package includedIn-person engineering culture in San Francisco or NYCOpportunity to work on core infrastructure powering frontier AI and marketplace systems at massive scaleHigh ownership environment with direct impact on company growth and operational performanceRelocation support and strong employee benefits packageExposure to cutting-edge AI workflows, operational systems, and large-scale distributed infrastructure