What Is Serverless Architecture?
Serverless is a cloud execution model where your code runs in stateless functions that scale automatically — you pay per execution, not per server-hour.
"Serverless" doesn't mean no servers. It means you don't manage them. Your code runs as functions that spin up on demand and shut down after execution.
How it works:
- You write a function (e.g. a Next.js API route, a Supabase Edge Function)
- The cloud platform runs it when triggered (HTTP request, database event, schedule)
- The platform handles scaling, uptime, and infrastructure
Common serverless platforms:
- Vercel — Next.js API routes and Edge Functions
- Supabase Edge Functions — Deno runtime, runs close to the database
- AWS Lambda — foundational serverless, extensive trigger support
- Cloudflare Workers — V8 isolates, ultra-low latency at the edge
Why it matters for SaaS MVPs: You don't need a dedicated server to ship a production API. A Next.js app on Vercel gives you serverless API routes, server components, and edge middleware — with zero server management.
Cold starts: The main trade-off. A function that hasn't run recently takes slightly longer on its first invocation. For most SaaS apps this is not a real problem. For latency-sensitive applications, keep functions warm or use edge runtimes.
Serverless vs. long-running server: Most SaaS MVPs: serverless. Real-time WebSocket servers, heavy background jobs: traditional server or dedicated worker.