Building Scalable SaaS with FastSaaS

Building a SaaS that can scale from your first customer to thousands requires thoughtful architecture decisions from day one. FastSaaS is built with scalability in mind.

Multi-Tenancy Architecture

FastSaaS uses an organization-based multi-tenancy model:

// Each organization has its own isolated data
const organization = await prisma.organization.findUnique({
  where: { slug: "acme-corp" },
  include: {
    members: true,
    subscriptions: true,
  },
});

Benefits of This Approach

Data Isolation - Each organization's data is logically separated
Simple Queries - No complex row-level security
Easy Onboarding - Users can belong to multiple organizations
Flexible Billing - Bill per organization or per user

Database Optimization

Indexing Strategy

FastSaaS includes optimized indexes for common queries:

model User {
  id    String @id @default(cuid())
  email String @unique

  @@index([email])  // Fast email lookups
  @@map("users")
}

Connection Pooling

For production, use connection pooling with PgBouncer or Prisma Accelerate:

DATABASE_URL="postgresql://user:pass@localhost:5432/db?connection_limit=5"

Caching with Redis

FastSaaS includes Redis integration for:

Session storage
API rate limiting
Email queue processing
Real-time features

import { redis } from "@/lib/redis";

// Cache expensive queries
const cachedData = await redis.get("dashboard:stats");
if (!cachedData) {
  const stats = await calculateStats();
  await redis.set("dashboard:stats", JSON.stringify(stats), "EX", 3600);
}

Horizontal Scaling

FastSaaS is designed to run on multiple instances:

Stateless Application - No server-side session storage
External Services - Database, Redis, email are external
Docker Ready - Easy container deployment
Edge Compatible - Works with Vercel Edge Functions

Monitoring & Observability

Built-in Health Checks

// /api/health endpoint
{
  "status": "healthy",
  "database": "connected",
  "redis": "connected",
  "uptime": "24h 35m"
}

Error Tracking

Integrate with Sentry for production error monitoring:

import * as Sentry from "@sentry/nextjs";

Sentry.captureException(error);