Senior Software Engineer - PSA Liquidity

Collectors creates technology and value-added services for collectors, including grading, authentication, vaulting, and marketplace solutions. The Senior Software Engineer will build and own the PSA Liquidity Platform, developing buyer and seller experiences, pricing and targeting systems, and scalable marketplace infrastructure. The role partners cross-functionally to connect supply and demand and improve GMV, conversion, and offer-to-sale velocity.

Responsibilities:

• Lead development of our next-generation buyer platform: targeting, campaign management, budget controls, and analytics that let every type of buyer — from individual collectors to large-scale dealers — discover and acquire the right cards at scale
• Partner with Engineering and AI/ML to build a sophisticated, real-time targeting and ranking engine that maximizes marketplace GMV, conversion, and offer-to-sale velocity across channels
• Make it effortless for sellers to understand their options, price their items accurately, and complete a sale via the PSA Partner Offer or eBay Consignment channel with minimal friction
• Design and operate microservices and distributed, event-driven systems that power instant, accurate offers across millions of collectibles — with the low latency and reliability our customers expect. You'll make pragmatic, high-conviction architecture calls and own the quality of what you ship across the full stack
• Use AI tooling across the development lifecycle to move faster and raise quality, and bring a strong point of view on how AI changes the way we design, build, and operate software
• Take projects from 0 to 1 — from an ambiguous problem to a shipped, instrumented, production product — and wear whatever hat the moment requires, whether that's frontend, backend, infrastructure, or data
• Translate strategy into clear technical plans, specs, and user stories. Coordinate delivery across dedicated and partner engineering teams, and keep stakeholders aligned and projects moving
• Ensure seamless liquidity handoffs across the broader PSA enterprise, from Grading to Collection Management to Vaulting, reducing friction and resolving cross-system dependencies that span payments, logistics, and risk
• From executive reviews to engineering standups, synthesize complexity, articulate tradeoffs, and bring people with you — clearly, in writing and in person

Requirements:

• 6+ years engineering experience. You have a track record of designing, shipping, and scaling products 0-to-1 that have measurable business impact
• You have strong proficiency in Java (Spring Boot) and equally comfortable in modern frontend frameworks like React and Svelte, moving fluidly across the stack
• You've designed and operated microservices and Kafka-based event-driven architectures, run workloads on Kubernetes, and know your way around the AWS ecosystem
• You instrument what you ship using tools such as Datadog, New Relic, or OpenTelemetry. You're comfortable building dashboards, setting up monitoring/alerting, and using distributed tracing to debug production issues
• You build with AI tooling across the SDLC - from planning and code generation to review and debugging. You lean on your experience to make high-conviction calls quickly
• You naturally decompose complex, multi-service systems into clean boundaries and intuitive interfaces, without losing sight of the customer experience
• A strong written and verbal communicator who aligns engineers, product partners, and stakeholders without direct authority, makes crisp calls, and brings people with you
• You have an extreme ownership mindset and will wear any hat required to get the job done. You thrive in a fast-moving, self-directed environment — you set the bar, hold it, and take full accountability for outcomes
• We believe there is significant value in onsite partnership and team collaboration, and candidates within 1-hour commuting distance of the office may be expected to work onsite most of the time
• Ideally 2+ years operating as a Senior IC or equivalent technical leadership level at a high-growth company or a scaled consumer platform
• Mobile experience using Flutter/Dart is a plus
• Passion for collecting is a plus