Sr Software Engineer - API Platform, Product Engineering (Python/Typescript)

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 customers use every day. Our teams design and deliver features that sit 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 used by Product Engineering for agentic AI use cases. We partner closely with internal Workday teams to design APIs and patterns that are consistent, reliable, scalable, and easy to consume.You will help shape the API foundation, architecture, and operating model that makes it easy for Product Engineering to build agent-ready, high-quality APIs. This includes working on product capabilities end to end, from product and domain modeling through backend implementation, API endpoint design, testing, and production operations.If you enjoy building products, services, and APIs that other engineers, customers, and AI agents love to use, you’ll feel at home on this team.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, backend services, and frameworks that support Workday’s next generation of products and agents.You will help translate product requirements and user workflows into scalable services, object models, data models, and API endpoints. You will bring hands-on experience in designing and building products end to end, and you will apply strong object-oriented modeling and software design principles to create maintainable, extensible, and production-ready systems.You will shape API design, drive performance and observability improvements, and coach and grow future senior engineers across the team.You will:Lead design and implementation of APIs, backend services, and platform features used by Product Engineering teams.Champion consistent API standards, object modeling practices, design patterns, and tooling that align with cross-org guidance while solving concrete product needs.Help Product Engineering teams expose product capabilities via REST, GraphQL, SOAP, and emerging integration patterns in a way that is friendly to agents, internal teams, and external consumers.Translate end-to-end product functionality into clear service boundaries, domain models, and well-designed API endpoints.Contribute to large-scale systems that require high availability, performance, extensibility, observability, and operational excellence.What You’ll DoLead end-to-end design and development of complex backend services, product capabilities, and APIs.Design and build product functionality end to end, including domain modeling, object modeling, service design, API contract definition, implementation, testing, deployment, and production support.Drive consensus with product managers, architects, and partner teams to define clear, evolvable API contracts, object models, and data models using OpenAPI and internal standards.Create API endpoints that expose product functionality clearly, consistently, securely, and at scale.Apply object-oriented modeling concepts and domain-driven design principles to create scalable, maintainable, and extensible software architectures.Drive performance and scalability improvements, including latency optimization, capacity planning, caching strategies, and resiliency patterns for mission-critical product flows.Design and implement observability for product APIs, including metrics, tracing, structured logging, and dashboards, and use data to drive technical decisions and SLOs.Collaborate on frameworks, tools, and patterns that make it simpler for other Product Engineering teams to define, publish, consume, and maintain APIs.Work with data platform teams to define patterns for exposing data safely and efficiently to API and agent workflows.Provide technical leadership through design reviews, RFCs, spike investigations, code reviews, and coaching junior and mid-level engineers.Participate in and improve on-call and incident response processes; own root cause analysis and long-term remediation for significant issues.Act as a trusted technical partner to teams across Product Engineering, helping them make product design, API design, integration, and architecture decisions.About YouBasic Qualifications8+ years of experience in software development engineering, architecting, building, and scaling robust and efficient software systems.5+ years of experience in software engineering, with hands-on experience in object-oriented modeling and software design concepts such as domain modeling, abstraction, encapsulation, extensibility, and maintainable service design4+ years of experience designing API endpoints that expose product functionality clearly, consistently, securely, and at scale.Bachelor’s degree in Computer Science, Engineering, or related discipline, or equivalent practical experience.Other QualificationsStrong 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.Solid experience with API development, including REST, SOAP, GraphQL, OpenAPI/Swagger-driven design, and designing and building scalable, secure APIs and API integration patterns.Experience creating API endpoints that map clearly to product functionality, domain concepts, and customer-facing workflows.Hands-on experience building and operating large-scale systems with complex product domains, high transaction volumes, and enterprise-grade reliability requirements.Strong understanding of code testing methodologies, such as contract testing, performance testing, system testing, and integration testing, and experience with advanced testing tools or frameworks such as JUnit, ScalaTest, Postman, Mockito, Jacoco, or Scoverage.Strong understanding of object-oriented design principles, including SOLID, abstraction, encapsulation, inheritance, composition, and polymorphism.Practical experience applying domain-driven design concepts, object-oriented modeling, and common architectural patterns, such as layered architecture and hexagonal architecture, to scalable software systems.Solid understanding of software development principles and advanced development methodologies such as continuous delivery, trunk-based development, and test-driven or behavior-driven development.Solid experience with source control management tools such as Git and advanced branching and merging strategies across multiple teams or services.Proven ability to lead team collaboration within a software development team and mentor junior and mid-level engineers through design reviews, technical guidance, code reviews, and knowledge sharing.Strong skills in technical writing, including comprehensive technical specifications, design documents, RFCs, API documentation, and integration best-practice guides.Experience leveraging AI-assisted code generation and review tools, such as Cursor, Claude Code, or GitHub Copilot, to improve development speed and quality.Exposure to MCP or similar agent/tool integration models is a strong plus.Workday Pay Transparency StatementThe annualized base salary ranges for the primary location and any additional locations are listed below. Workday pay ranges vary based on work location. As a part of the total compensation package, this role may be eligible for the Workday Bonus Plan or a role-specific commission/bonus, as well as annual refresh stock grants. Recruiters can share more detail during the hiring process. Each candidate’s compensation offer will be based on multiple factors including, but not limited to, geography, experience, skills, job duties, and business need, among other things. For more information regarding Workday’s comprehensive benefits, please click here.Primary Location: USA.CA.PleasantonPrimary Location Base Pay Range: $176,000 USD - $264,000 USDAdditional US Location(s) Base Pay Range: $148,200 USD - $264,000 USDOur Approach to Flexible WorkWith Flex Work, we’re combining the best of both worlds: in-person time and remote. Our approach enables our teams to deepen connections, maintain a strong community, and do their best work. We know that flexibility can take shape in many ways, so rather than a number of required days in-office each week, we simply spend at least half (50%) of our time each quarter in the office or in the field with our customers, prospects, and partners (depending on role). This means you'll have the freedom to create a flexible schedule that caters to your business, team, and personal needs, while being intentional to make the most of time spent together. Those in our remote "home office" roles also have the opportunity to come together in our offices for important moments that matter.Pursuant to applicable Fair Chance law, Workday will consider for employment qualified applicants with arrest and conviction records.Workday is an Equal Opportunity Employer including individuals with disabilities and protected veterans.Workday is committed to providing reasonable accommodations for qualified individuals during our application process, in order to perform one or more essential functions of their job, as well as regarding the use of AI tools for employment decision-making to any degree. Please see below for more details including how to request an accommodation as a qualified veteran, due to a disability or for religious reasons, or as otherwise provided under applicable law. Workday prohibits taking adverse action against any candidate or employee for reporting a possible violation of this policy, requesting one or more work accommodations, exercising a privacy right, or cooperating in an investigation in accordance with applicable law. Any employee who retaliates against a candidate or employee for doing so may be subject to disciplinary action, up to and including termination of employment, to the fullest extent allowable under applicable law. If you require a reasonable accommodation, you may email View email address on us.fitly.work, as far in advance as possible.Are you being referred to one of our roles? If so, ask your connection at Workday about our Employee Referral process!At Workday, we value our candidates’ privacy and data security. Workday will never ask candidates to apply to jobs through websites that are not Workday Careers. Please be aware of sites that may ask for you to input your data in connection with a job posting that appears to be from Workday but is not.In addition, Workday will never ask candidates to pay a recruiting fee, or pay for consulting or coaching services, in order to apply for a job at Workday.SummaryLocation: USA, CA, PleasantonType: Full Time