Sr. Fullstack Engineer - Identity Platform

AI AT ZAPIER

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Job Posted: March 17, 2026

Location: Americas - North, Central and South America

Zapier's mission is to enable enterprise companies to build and maintain dependable AI workflows at scale. The Identity Platform team builds the golden path that every product team uses to deliver reliable, consistent, and secure experiences to these customers. Authentication, session management, and credential infrastructure are the foundation. Get them right, and every product team ships faster with confidence. We're hiring a Senior Fullstack Engineer to own this foundation, drive the strategic and architectural direction of this layer for years to come, and directly unlock our largest enterprise deals.

WHAT YOU'LL WORK ON

- Enterprise authentication infrastructure. You'll design and extend the systems that handle SAML SSO, SCIM provisioning, OAuth/OIDC flows, multi-factor authentication, login, sign-up, and secure session for organizations with thousands of users. That spans the full auth surface: SCIM-driven user provisioning and de-provisioning, invitation flows, 2FA setup, SSO-enforced login, domain capture for auto-routing new signups, and session hardening. Reliability, latency, and efficiency are non-negotiables; auth is the most critical-path system at the company. You'll make these systems faster, more resilient, and easier for other teams to integrate with.

- User session auth across services. Zapier is a multi-service platform. You'll own how user sessions propagate...