Cloud-Native Auth SystemCloud-Native Auth System

Overview

A comprehensive authentication and authorization system designed for multi-tenant SaaS applications. Implements zero-trust security principles with fine-grained access control.

Problem

Multi-tenant applications need authentication, authorization, session control, and auditability without letting tenant boundaries leak through shared infrastructure.

Architecture

• Auth Engine: OAuth 2.0 / OIDC compliant with JWT token management
• RBAC: Hierarchical role-based access control with policy-as-code
• Session Management: Redis-backed distributed sessions with automatic rotation
• Audit: Complete audit trail with tamper-evident logging

Engineering Tradeoffs

• Used JWTs for stateless API authorization while keeping Redis sessions for revocation control
• Modeled permissions through roles and policies instead of scattering checks across services
• Treated audit logs as product data, not only operational logs

Key Achievements

• Handles authentication traffic for multi-tenant workloads
• Supports tenant isolation with role-based permission models
• Implements audit logging and security-focused controls
• Includes compliance reporting support for security review workflows

Validation Focus

• Test tenant isolation with cross-tenant access attempts
• Verify token expiry, refresh, and session revocation paths
• Review audit trails for authorization failures and privileged actions