Complete Deployment Guide 2025

📖 What Is Backend Deployment?

Backend deployment = running your server-side app (APIs, auth, DB connections, logic) live on the internet so your frontend or users can access it.

🗂️ Backend Hosting Platforms (2025)

⚡ Quick Start Code Examples

Minimal Express Server

import express from 'express'
const app = express()
const PORT = process.env.PORT || 5000
app.get('/', (req, res) => res.send('API is running...'))
app.listen(PORT, () => console.log(`Server running on ${PORT}`))

Enable CORS

import cors from 'cors'
app.use(cors())

🧠 What Is Database Hosting?

Database hosting means storing and running your database (like MongoDB, PostgreSQL, or MySQL) on a remote server or cloud platform so your backend or app can access it via the internet.

☁️ Where to Host Databases (Free + Paid + Student Options)

🛠️ How to Connect DB in Backend (Example: MERN)

Example with MongoDB + Express:

// server.js
import express from "express";
import mongoose from "mongoose";
import dotenv from "dotenv";

dotenv.config();
const app = express();

mongoose.connect(process.env.MONGO_URL)
  .then(() => console.log("Database connected"))
  .catch(err => console.log(err));

app.listen(5000, () => console.log("Server running"));