Senior Software Engineer - Agentic AI & API Platform

Your work days are brighter here.We’re obsessed with making hard work pay off, for our people, our customers, and the world around us. As a Fortune 500 company and a leading AI platform for managing people, money, and agents, we’re shaping the future of work so teams can reach their potential and focus on what matters most. The minute you join, you’ll feel it. Not just in the products we build, but in how we show up for each other. Our culture is rooted in integrity, empathy, and shared enthusiasm. We’re in this together, tackling big challenges with bold ideas and genuine care. We look for curious minds and courageous collaborators who bring sun-drenched optimism and drive. Whether you're building smarter solutions, supporting customers, or creating a space where everyone belongs, you’ll do meaningful work with Workmates who’ve got your back. In return, we’ll give you the trust to take risks, the tools to grow, the skills to develop and the support of a company invested in you for the long haul. So, if you want to inspire a brighter work day for everyone, including yourself, you’ve found a match in Workday, and we hope to be a match for you too.About the TeamThe Product Engineering organization builds the product experiences that Workday customers use every day. Our teams design and deliver features on top of Workday's core platforms and services, and increasingly depend on powerful, well-designed APIs to support agentic experiences and AI-driven scenarios. This team focuses on evolving the API surface and supporting mission-critical product flows for agentic AI use cases. We are essentially building the "neural pathways" for Workday's next-generation applications — designing and scaling APIs that are optimized not only for human developers, but for AI agents to understand and act on autonomously. We partner closely with internal Workday teams to design APIs and patterns that are consistent, reliable, and easy to consume. We also act as a center of excellence for API governance, setting the standards that help the entire organization build with confidence.About the RoleAs a Senior Software Development Engineer in Product Engineering, you will be a technical leader in designing and delivering high-throughput, low-latency APIs and frameworks that power Workday's next generation of products and agents. You will shape API design, drive performance and observability improvements, and help grow future senior engineers across the team. This role is crucial because agentic AI changes how APIs must be built. For an AI agent to successfully process an invoice, update an employee record, or orchestrate a complex workflow within Workday, the underlying APIs must be highly deterministic, self-describing, and resilient. You will be at the center of making that possible.In this role, you will:Lead end-to-end design and development of complex backend services and APIs used by Product Engineering teamsDrive consensus with product managers, architects, and partner teams to define clear, evolvable API contracts and data models using OpenAPI and internal standardsChampion consistent API standards, patterns, and tooling that align with cross-organization guidance while solving concrete product needsHelp Product Engineering teams expose capabilities via REST, GraphQL, and emerging integration patterns in a way that is friendly to agents and external consumersDrive performance and scalability improvements, including latency optimization, capacity planning, and resiliency strategies for mission-critical product flowsDesign and implement observability for product APIs (metrics, tracing, structured logging) and use data to inform technical decisions and SLOsCollaborate on frameworks, tools, and patterns that make it simpler for other Product Engineering teams to define, publish, and maintain APIsWork with data platform teams to define patterns for exposing data safely and efficiently to API and agent workflowsProvide technical leadership through design reviews, RFCs, spike investigations, and coaching junior engineersParticipate in and improve on-call and incident response processes; own root cause analysis and long-term remediation for significant issuesAct as a trusted technical partner to teams across Product Engineering, helping them make sound API and integration decisionsAbout YouBasic Qualifications:8+ years of experience in software development engineering, architecting, building, and scaling robust and efficient backend software systems.5+ years of hands-on experience with TypeScript or Python in production environments.4+ years of dedicated experience designing, building, and maintaining scalable web APIs (REST and/or GraphQL) with a strong emphasis on contract-first design (e.g., OpenAPI/Swagger)3+ years of experience working with distributed systems architecture, handling high-throughput workloads, concurrency management, or advanced caching strategies2+ years of experience implementing and managing production observability (e.g., structured logging, distributed tracing, metrics) and owning on-call/incident remediation for critical services. Other Qualifications:Strong ability in Algorithmic Thinking, including advanced data structures and algorithms such as graphs, concurrent data structures, and caching/eviction strategies, to design and optimize solutions for complex API orchestration, request routing, and high-throughput workloads.Strong understanding of Code Testing methodologies, such as contract testing, performance testing, and system/integration testing, and experience with advanced testing tools or frameworks (e.g., JUnit, ScalaTest, Postman, Mockito, and coverage tools such as Jacoco or Scoverage).Strong understanding of Object-Oriented Design (OOD) principles like SOLID, domain-driven design concepts, and common architectural patterns (e.g., layered architecture, hexagonal architecture) and their application in designing scalable software architectures.Solid understanding of Software Deve