Beyond "Hello World"

Building a SaaS MVP is easy. Building a platform that scales to 100,000 users, maintains 99.99% uptime, and complies with SOC2 is a different beast.

At AIVN, we specialize in high-scale systems. Here is the architectural blueprint we use for enterprise-grade SaaS.

1. The Frontend: Speed at the Edge

We default to Next.js deployed on Vercel. Why? Edge Caching. Static assets and ISR (Incremental Static Regeneration) pages are served from a CDN node close to the user. This ensures sub-100ms load times globally.

We use React Server Components (RSC) to move heavy computation off the client. Your phone shouldn't need to process 5MB of JSON; the server should do it and send only the HTML.

2. The Database: Serverless & Scalable

The days of provisioning a fixed AWS RDS instance are fading. We prefer serverless Postgres (like Supabase or Neon).

• Connection Pooling: Essential for serverless functions to avoid exhausting database connections.
• Row Level Security (RLS): We bake security into the database itself. Policies like auth.uid() == user_id ensure that a bug in the API doesn't leak data.

3. The Backend: Event-Driven

Monoliths are fine for starting, but they choke under load. We decouple heavy tasks using queues.

• User uploads a CSV? Don't parse it in the request.
• Pattern: API pushes job to a Redis Queue (BullMQ) -> Worker processes it -> Worker updates DB -> WebSocket pushes notification to frontend.

This keeps the UI snappy.

4. Multi-Tenancy

For B2B SaaS, data isolation is critical. We typically use Logical Isolation (discriminator columns like org_id) enforced by RLS. It's cheaper and easier to manage than creating a separate database for every customer, yet mathematically secure if implemented correctly.

5. Security & Compliance

Security isn't an addon; it's a layer.

• Auth: Clerk or Supabase Auth. Never roll your own crypto.
• Headers: Strict Content Security Policy (CSP) to prevent XSS.
• Auditing: Every write action logs to an immutable audit trail.