Multi-Tenant SaaS Backend Audit: FastAPI + PostgreSQL Tenant Isolation Review (Python)

We are seeking an experienced backend developer to audit our multi-tenant SaaS application. The task involves reviewing the current implementation of tenant isolation using FastAPI and PostgreSQL. The ideal candidate will have a strong understanding of database security and architecture, ensuring that each tenant's data is properly isolated and secure. The audit should identify any potential security vulnerabilities and provide recommendations for improvements.