People Systems Lead - HRIS

Lambda, The Superintelligence Cloud, is a leader in AI cloud infrastructure serving tens of thousands of customers. Our customers range from AI researchers to enterprises and hyperscalers. Lambda's mission is to make compute as ubiquitous as electricity and give everyone the power of superintelligence. One person, one GPU. If you'd like to build the world's best AI cloud, join us. *Note: This position requires presence in our San Francisco or San Jose office location 4 days per week; Lambda’s designated work from home day is currently Tuesday. We are seeking an experienced People Technology leader to own and scale our People Systems platform, with Workday as the core tool. This role will be central to deploying Workday HCM, Payroll, Benefits, Absence, and Talent capabilities as the company prepares for and operates as a public company. You will partner closely with the People team, Finance, Accounting, Legal, and Business Technology to design and deliver HR processes, payroll operations, and cross-functional workflows that give leadership accurate, auditable visibility into workforce data. Your responsibilities will include architecting Workday's tenant configuration, supervisory and security models, payroll setup, integration layer, and reporting framework. You will manage the implementation partner relationship through go-live, then build the in-house team that owns the platform on an ongoing basis. This role requires deep Workday domain expertise, payroll fluency, and the ability to translate People team needs into scalable, SOX-defensible solutions. What You’ll Do - Platform Ownership: Own the end-to-end design, build, and administration of Workday HCM, including tenant configuration, supervisory orgs, business processes, security model, and environment management across implementation, sandbox, and production tenants. - Payroll Deployment & Operations: Lead the deployment of Workday Payroll (US first, international as scoped) with full SOX-compliant controls over pay calculation, tax filing, GL posting to NetSuite, and off-cycle processing. Own ongoing payroll operations partnership with the People and Accounting teams. - Integration & Data Architecture: Design and manage integrations between Workday and upstream/downstream systems (NetSuite, BigQuery, Okta/Lumos, benefits carriers, 401(k), ATS, perf, equity admin) using Workday Studio, EIBs, Core Connectors, and Workato as appropriate. - Implementation Partner Management: Lead the Workday implementation partner relationship end-to-end: scope, SOW, sprint cadence, UAT, cutover, hypercare. Hold the partner accountable to deliverables and timeline. - Reporting & Analytics: Build the People reporting and analytics layer: headcount close, attrition, comp planning, DEI, payroll register reconciliation. Feed clean headcount actuals into Pigment EPM for FP&A. - SOX & Compliance: Establish and enforce controls around payroll, comp, terminations, access provisioning, and master data changes. Partner with external SOX advisors on ITGC and IPE design for the People stack. - Team Building: Hire and grow a small in-house People Technology team (2-3 ICs over 12-18 months) covering Workday HCM/Payroll admin, integrations and reporting, and adjacent People Ops tooling. - Stakeholder Enablement: Train and support end users across the People team, drive adoption, and build documentation and governance standards for tenant changes and release management. - Roadmap & Strategy: Develop and maintain a multi-quarter platform roadmap aligned with Lambda's People function maturity goals, partnering with Business Technology and People leadership to prioritize enhancements You - Experience: 10+ years in HRIS / People Systems, with at least 4+ years of hands-on Workday HCM and Payroll implementation and administration experience. At least one full-cycle Workday implementation including Payroll go-live as the customer-side architect or in-house owner. Prior experience at a high-growth or pre-IPO / pu