Software Engineer, Backend

ABOUT MERCOR Mercor's mission is to organize human intelligence to power the AI economy. We're a leading AI data company, building the layer between human expertise and frontier models. Millions of domain experts on the platform are paid over $4 million per day to train frontier AI models. Mercor's APEX benchmark family measures AI's real-world impact on professional work. Mercor Enterprise brings this same infrastructure to Fortune 500 companies: helping companies capture how their best people actually work, translating that expertise directly back into agents. Mercor is creating a new category of work where expertise powers AI advancement. Achieving this requires an ambitious, fast-paced and deeply committed team. You’ll work alongside researchers, operators, and AI companies at the forefront of shaping the systems that are redefining society. Mercor is a profitable Series C company valued at $10 billion. We work in-person five days a week in our San Francisco, NYC, or London offices. ABOUT MERCOR Mercor is defining the future of work. We partner with leading AI labs and enterprises to provide the human intelligence essential to AI development. Our vast talent network trains frontier AI models in the same way teachers teach students: by sharing knowledge, experience, and context that can't be captured in code alone. Today, more than 30,000 experts in our network collectively earn over $2 million a day. Mercor is creating a new category of work where expertise powers AI advancement. Achieving this requires an ambitious, fast-paced and deeply committed team. You’ll work alongside researchers, operators, and AI companies at the forefront of shaping the systems that are redefining society. Mercor is a profitable Series C company valued at $10 billion. We work in-person five days a week in our new San Francisco headquarters. About the Role As a Member of Technical Staff of talent experience, you'll own the shared backend architecture that underpins every user journey for talent network at Mercor. Mercor's products—talent matching, assessment, expert workflows—are growing faster than any single team can architect for. You'll define the technical direction of the systems they all depend on: core services, data models, APIs, and infrastructure patterns that must scale with a network of tens of thousands of experts and the demands of the world's leading AI labs. You'll set the standards that dozens of engineers build on, pay down the architectural decisions that no longer fit, and make the ones that will still be right three years from now. This is a hands-on technical leadership role, not a management role. You'll write code, review the designs that matter most, and act as the connective tissue between product teams—partnering directly with engineering leadership to shape how the organization builds. What You’ll Do - Own the architecture of Mercor's shared backend systems—core services, data models, APIs, and cross-product infrastructure. - Define and drive the long-term technical strategy for backend architecture across the organization. - Design systems for scale, reliability, and evolvability, and lead the highest-stakes technical decisions and design reviews. - Identify and pay down architectural debt that slows product teams, and lead complex cross-team migrations. - Establish backend engineering standards, patterns, and best practices adopted across all product teams. - Stay hands-on: prototype critical systems, ship production code, and unblock teams on their hardest technical problems. - Mentor senior engineers and raise the technical bar across the engineering organization. - Partner with engineering and product leadership on build-vs-buy decisions, platform investments, and technical hiring. What We’re Looking For - 8+ years of professional backend engineering experience, including 3+ years operating at a Senior level or above. - Deep expertise in distributed systems, service architecture, data modeling, and API design at…