7 Myths About Full Stack Development Career Nobody Tells You

<!-- A to-do list without any framework -->
<input id="task" placeholder="New task">
<button id="add">Add</button>
<ul id="list"></ul>
<script>
  const list = document.getElementById('list');
  document.getElementById('add').addEventListener('click', () => {
    const input = document.getElementById('task');
    const text = input.value.trim();
    if (!text) return;
    const li = document.createElement('li');
    li.textContent = text;            // textContent avoids HTML injection
    li.addEventListener('click', () => li.remove());
    list.appendChild(li);
    input.value = '';
  });
</script>

// Run with Node 18+: node http_basics.js
const http = require('http');

const server = http.createServer((req, res) => {
  if (req.method === 'GET' && req.url === '/api/health') {
    res.writeHead(200, { 'Content-Type': 'application/json' });
    return res.end(JSON.stringify({ status: 'ok' }));
  }
  res.writeHead(404, { 'Content-Type': 'application/json' });
  res.end(JSON.stringify({ error: 'not found' }));
});

server.listen(3000, () => console.log('http://localhost:3000/api/health'));

// A bug report: 'Orders page shows wrong total'
// Step 1: reproduce with a small test
function orderTotal(items) {
  return items.reduce((sum, i) => sum + i.price * i.qty, 0);
}

const items = [{ price: 199.99, qty: 3 }, { price: 0.1, qty: 3 }];
console.log(orderTotal(items));        // floating-point noise

// Step 2: fix by working in paise (integers)
function orderTotalPaise(items) {
  return items.reduce((sum, i) => sum + Math.round(i.price * 100) * i.qty, 0);
}
console.log(orderTotalPaise(items) / 100);   // 600.27

## What
Fix incorrect order total caused by floating-point rounding.

## Why
Bug #142: totals showed values like 600.2699999.

## How
- Calculate totals in paise (integers)
- Format to rupees only for display
- Added 4 unit tests for totals

## Checks
- [x] Tests pass locally and in CI
- [x] Checked orders page on mobile
- [x] No API contract changes

// Suppose an assistant generated this search endpoint
// (Express + a SQL client)
app.get('/api/users', async (req, res) => {
  const q = req.query.name;
  // PROBLEM: string concatenation allows SQL injection
  const rows = await db.query("SELECT * FROM users WHERE name = '" + q + "'");
  res.json(rows);
});

// Reviewed version: parameterised query and limited columns
app.get('/api/users', async (req, res) => {
  const q = String(req.query.name || '');
  const rows = await db.query('SELECT id, name FROM users WHERE name = $1', [q]);
  res.json(rows);
});

// npm i -D jest   Run: npx jest
function isValidEmail(email) {
  return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
}

test('accepts normal email', () => {
  expect(isValidEmail('asha@example.com')).toBe(true);
});
test('rejects missing domain', () => {
  expect(isValidEmail('asha@')).toBe(false);
});
test('rejects spaces', () => {
  expect(isValidEmail('asha @example.com')).toBe(false);
});

module.exports = { isValidEmail };

Stage 1  HTML, CSS, JavaScript, Git, HTTP basics
Stage 2  One frontend framework (e.g. React)
Stage 3  One backend (e.g. Node.js + Express), REST APIs, auth
Stage 4  One database (e.g. PostgreSQL), SQL, data modelling
Stage 5  Testing, Docker, CI, deployment
Stage 6  Two complete projects, code reviews, interview practice

Project 1: Plain JS + small Node API (fundamentals)
Project 2: Full stack app in your chosen stack with auth and DB
Project 3: Contribute a fix or feature to an existing open-source repo

Project 3 proves you can work on code you did not write.

[ ] Did I build or fix something end to end?
[ ] Did I read someone else's code?
[ ] Did I write tests for new code?
[ ] Did I review any generated code line by line?
[ ] Did I deploy or update a live demo?