PaaS abstracts away the server entirely. You push code, the platform handles building, deploying, scaling, SSL, and infrastructure. You focus purely on your application.
# Your project needs:
# 1. A start command (in package.json, Procfile, or Dockerfile)
# 2. Listen on the PORT environment variable
# package.json
{
"scripts": {
"start": "node server.js"
}
}
# server.js — must use process.env.PORT
const port = process.env.PORT || 3000;
app.listen(port, '0.0.0.0');
# Deploy:
# Option A: Connect GitHub repo in Railway dashboard (auto-deploys on push)
# Option B: Railway CLI
npm install -g @railway/cli
railway login
railway init
railway up
Procfile (Heroku-style Process Declaration)
# Procfile — tells the platform what processes to run
web: node server.js
worker: node worker.js
release: node migrate.js # Runs before each deploy
When PaaS is the Right Choice
Use PaaS when:
• Small team (1-5 devs) that wants to focus on product, not infrastructure
• Predictable, moderate traffic (not massive spikes)
• Standard web app (HTTP server + database)
• Fast iteration speed matters more than cost optimization
• You don't need custom system-level software
Avoid PaaS when:
• Cost-sensitive at scale (PaaS markup is 3-10x vs raw compute)
• Need custom networking, kernel modules, or system packages
• Compliance requires specific infrastructure control
• Traffic is highly variable (serverless may be cheaper)
• You need persistent local storage or specific hardware
The PaaS Cost Trap
PaaS is cheap to start but expensive to scale. A $7/mo Render service running a Node.js app is great. But when you need 4 instances + a managed database + Redis + background workers, you're suddenly paying $200/mo for what a $40/mo VPS could handle.
The professional pattern: Start on PaaS for speed. When monthly costs exceed what a VPS + your time would cost, migrate to containers on a VPS or IaaS. This is called "graduating" from PaaS.