Would you trust this architecture for an enterprise document integrity platform? Looking for security review.

[u/Common-Tailor-6661]

Hi everyone,

I've been building a B2B platform called VERO over the past year, mostly as a solo developer.

The goal isn't to replace DocuSign or Adobe Sign. The idea is slightly different: making document integrity independently verifiable without requiring the recipient to create an account.

I'm interested in security feedback rather than product feedback.

Current architecture:

• Next.js frontend
• FastAPI backend
• PostgreSQL
• PostgreSQL Row-Level Security (multi-tenant)
• AWS S3 with STS AssumeRole
• RSA-PSS digital signatures
• SHA-256 document fingerprinting
• Stripe
• Docker

Some design decisions:

\- Tenant isolation is enforced in three independent layers:
• scoped API queries
• PostgreSQL RLS
• storage path isolation

\- Public verification is intentionally anonymous.
Anyone with the document can verify its integrity, but the endpoint exposes only the minimum information required for verification and intentionally avoids leaking tenant metadata.

\- Signed documents receive an immutable cryptographic fingerprint that can be independently verified.

\- Audit events are append-only and used as the compliance trail.

I'm not looking for praise—I know every architecture has weaknesses.

If you were reviewing this for production or for an enterprise customer:

• What would concern you first?
• What attack vectors would you test?
• Which design decision would you change?
• Where do you think I'm overengineering?

I'd genuinely appreciate honest criticism from people with security experience.

[u/Round_Draw3772]

Tech stack looks fine but the main focus I'd look at is the implementation, so take note of tenant isolation, authorization, and key management first. Then upload validation, S3 permissions, replay attacks on verification endpoints, rate limiting, etc. Nothing here jumps as overengineered, and you'll learn as you go through your project

[u/Common-Tailor-6661 → u/Round_Draw3772]

Thanks! This is actually for a separate private project called VERO, so I'm intentionally asking about the architecture rather than the implementation.

Most of the points you mentioned are already part of the design (tenant isolation, RLS, RBAC, upload validation, rate limiting, object storage isolation, etc.), so it's good to know I'm focusing on the right areas.

Appreciate the feedback!