Senior Identity & Access Systems Architect

Jobtailor; Foster City (CA); Hybrid; USD 180,000 - 240,000; Full time

Job summary

Replit is seeking a Senior Backend Security Engineer to design, build, and operate identity and authorization systems protecting critical interactions across multi-tenant environments. You will lead the evolution of enterprise access controls, roles, and workspace policies using modern protocols like OAuth 2.0, JWT, and mTLS.

You will own the security health of shipped systems, collaborate with multiple teams, and drive secure migrations with shadow evaluation and telemetry.

Qualifications

• Experience shipping and operating security-sensitive backend systems in production, with focus on reliability, performance, incidents, and observability.
• Strong background in authentication, authorization, or identity systems (OAuth 2.0/OIDC, JWT, mTLS, Federation, RBAC, Zanzibar, policy engines).
• Deep understanding of multi-tenant security, least privilege, delegation, auditability, and threat modeling.
• Experience migrating security-sensitive systems without breaking callers (typed contracts, shadow evaluation, staged enforcement).
• Fluent in at least one production backend stack.

Responsibilities

• Design, build, and operate identity and authorization systems protecting critical interactions.
• Operate central authorization interfaces with typed principals, actions, resources, decisions, and explainable deny reasons.
• Evolve enterprise roles, groups, app access, entitlements, and workspace policies.
• Build and operate a Security Token Service and workload identity using OAuth 2.0, JWT/OIDC, SPIFFE/SPIRE, and mTLS.
• Lead migrations with shadow evaluation, feature gates, telemetry, and rollback plans.

Skills

OAuth 2.0

JWT

MTLS

Multi-Tenant Security

TypeScript

Tools

Go

Rust

Postgres

GRPC/Protobuf

Kubernetes

Envoy

Restate

Job description

Replit is seeking a Senior Backend Security Engineer to design, build, and operate identity and authorization systems protecting critical interactions across multi-tenant environments. You will lead the evolution of enterprise access controls, roles, and workspace policies using modern protocols like OAuth 2.0, JWT, and mTLS.

You will own the security health of shipped systems, collaborate with multiple teams, and drive secure migrations with shadow evaluation and telemetry.