Staff Software Engineer, Identity & Authorization

As a Software Engineer, you will design, build, and operate the identity and authorization systems that protect critical interactions on Replit, including Agent acting on behalf of a user or holding their own identity.

The work is guided by a few simple questions:

• Can every protected request prove which workload made it, which principal it represents, and who is acting on that principal's behalf?
• Can product teams express policy once and trust the same decision across web, mobile, Agent, and internal services?
• Can enterprise administrators control who can access each workspace, app, connector, and Agent capability without navigating a permission maze as well as having a legible ledger of decisions?
• Can Agent act for a user across long-running and durable work without receiving broad or long-lived credentials?
• Are identity and authorization fast, reliable, highly available, and observable enough for the product flows that depend on them?
• Design and operate central authorization interfaces with typed principals, actions, resources, decisions, explainable deny reasons, privilege attenuation, delegations, and obligations
• Evolve enterprise roles, groups, app access, entitlements, and workspace policy so common cases stay simple and advanced cases remain possible
• Build and operate Replit's Security Token Service and workload identity using OAuth 2.0 token exchange, JWT/OIDC, SPIFFE/SPIRE, and mTLS
• Threat-model delegation, confused-deputy risks, and cross-tenant movement, then make secure, fail-closed behavior the default
• Lead compatible migrations with shadow evaluation, feature gates, telemetry, and rollback plans, and own the SLOs, incidents, and operational health of the systems you ship
• Partner with Agent, Connectors, Enterprise, Security, and Infrastructure teams to turn product requirements into shared platform primitives
• Research and develop new innovative approaches to Authx in the Agentic world

Areas you might work in

• Authorization policy: evolve Replit's central policy decision point and migrate fragmented authorization checks to its typed contract.
• Agent delegation: extend the current delegation foundation so the user is the subject and Agent is the authenticated actor, with continuous validation and dynamic permission envelopes as work runs.
• Enterprise access control: evolve roles, groups, workspace policy, and app-level grants for both simple collaboration and complex organizations.
• Agent and service identity and reliability: operate the token and workload-identity systems that protect service-to-service traffic.