The Bootstrap Stack
When you're launching a SaaS, every dollar counts. Cloud providers like AWS can eat 40-60% of your early revenue. Here's how to build a production-grade stack on VPS infrastructure that scales with you.
Phase 1: 0-100 Users
Start with a single VPS (£15/mo). Run your web server, database, and background jobs on one instance. Use SQLite or a lightweight PostgreSQL setup. Focus on product-market fit, not infrastructure.
Phase 2: 100-1,000 Users
Split into two VPS instances: one for the web server, one for the database. Add Redis for caching and session management. This handles most SaaS workloads comfortably on £30-50/mo total.
Phase 3: 1,000-10,000 Users
At this scale, you need: load-balanced web servers (2-3 instances), a dedicated database cluster with replication, separate Redis and worker instances, and object storage for assets. Total: £100-200/mo on VPS vs £400-800/mo on AWS.
Key Architecture Decisions
- Database: Start with PostgreSQL (single node), add streaming replication at 5K users
- Caching: Redis from day one — it's cheap and prevents thundering herd problems
- Queue: Use Redis or RabbitMQ for background jobs (email, exports, webhooks)
- Storage: Use S3-compatible object storage for user uploads and assets
- Monitoring: Prometheus + Grafana is free and catches issues before users do
When to Migrate to Dedicated
At 10K+ users, consider migrating your database to a dedicated server for consistent I/O performance. Your web tier can stay on VPS instances behind a load balancer.
Real Savings Example
One of our customers (SaaS analytics platform) runs 15 VPS instances and 2 dedicated servers on Hostingowy for £450/mo. Their AWS quote for the same workload was £1,800/mo. That's 75% savings.