Principal API Architect, Product Engineering – Agent‑ APIs & Data

About the Team

Product Engineering builds the end‑to‑end product experiences that Workday customers use. Many of these experiences are now powered by agents and AI, which depend on a strong API foundation. This role sits in Product Engineering but operates across product pillars. You will work closely with Product Engineering teams as well as partner organizations. You will shape the API foundation, architecture and operating model that makes it easy for Product Engineering to build agent‑ready, high‑quality APIs.

We are seeking a Principal‑level API Architect in Product Engineering to lead our API strategy for agentic and integration‑heavy scenarios. You will own the API architecture vision for Product Engineering, set standards (OpenAPI, patterns, error models, observability), and partner with engineering leaders to make them real.

• Act as the “Chief API Architect” for Product Engineering.
• Define and evolve the API architecture, standards, and review processes that guide how Product Engineering teams design and deliver APIs.
• Partner with product and platform leaders to shape the operating model, including API champions across product pillars and a clear intake/prioritization path for API needs.
• Define the API architecture and governance model for Product Engineering, spanning REST, GraphQL, SOAP, and emerging integration models used by Workday agents and products.
• Establish and maintain API standards:
  OpenAPI contract guidelines, review and approval process; resource modeling, naming and pagination conventions; authentication/authorization and multi‑tenant patterns; error handling, retry semantics, and idempotency guidelines; versioning and deprecation policies.
• Shape API roadmaps with leaders, identify gaps, drive convergence on shared patterns and building blocks.
• Define reference architectures and patterns for agent‑ready APIs, orchestration patterns, data‑centric APIs, latency and observability standards.
• Lead critical cross‑team API design reviews and act as tie‑breaker on high‑impact decisions.
• Work closely with platform partners (Gateways, Trident, Web Service Frameworks, Core Services, Data Cloud, AI/Agent Factory) to ensure needs are represented and platform capabilities are consistently applied.
• Shape and help run a transparent intake and prioritization process for key API investments.
• Evaluate build/borrow/buy options for tools that help design, test, and operate APIs.
• Mentor senior engineers and managers on API architecture, distributed systems, and integration best practices.
• Communicate the API vision and status to senior stakeholders and influence product and resourcing decisions.

• 12+ years of experience building large‑scale, mission‑critical backend systems and APIs.
• 5+ years in a senior architecture or staff‑plus role with responsibility for cross‑team or organization‑wide API/platform architecture.
• Deep hands‑on experience using Type Script or Python to build web services and APIs.
• Understanding of the MCP protocol specification and architecture.
• Proven track record of setting and driving technical standards that scale across multiple teams.
• Able to prototype reference implementations and dive into code reviews when needed.

• Experience leveraging AI‑assisted code generation and review tools to improve development speed and quality.
• Strong expertise in distributed systems and cloud architectures, including high‑throughput, low‑latency services, horizontal scaling, and fault‑tolerant design.
• Extensive experience with edge and gateway patterns (routing, auth, throttling, rate limiting, transformation, multi‑tenant concerns).
• Demonstrated leadership in API governance: standards definition, contract review, documentation, and lifecycle management.
• Experience designing or evolving observability for APIs and using that data to define and monitor SLOs.
• Familiarity with agentic AI use cases and patterns for integrating LLMs/agents with enterprise APIs.
• Experience with data platforms and analytical stores (such as Data Cloud) and designing APIs that expose data safely and efficiently.
• Ability to collaborate and influence across Product…