Node & Express ⚡ Recently updated

Node.js & Express: Mock Interview (45 Minutes)

Section 1: Warm-up (5 min)

“Describe your backend project.”
“Why Node.js for this project?”
“What database did you use and why?”

Section 2: Node & Express Basics (10 min)

“What is Node.js?”
“What is middleware in Express?”
“Difference between req.params, req.query, req.body?”
“How does the middleware chain work?”

Section 3: API Design (8 min)

“Design REST routes for a todo resource.”
“Which status code for: created, not found, validation error, unauthorized?”
“How implement pagination?”

Section 4: Live Coding (12 min)

Pick ONE:

Option A: Auth middleware

“Write middleware that checks JWT in Authorization header.”

Option B: CRUD route

“Write POST /api/posts that validates title and creates a post.”

Option C: Error handler

“Write centralized error handling middleware.”

Section 5: Auth & Security (7 min)

“How store passwords?”
“JWT vs sessions?”
“What is CORS?”
“How prevent brute force login?”

Section 6: Project (3 min)

“Walk through your auth flow end-to-end.”
“One security improvement you’d add.”

Rubric

Area	1	3	5
REST design	Verbs in URLs	Correct routes	Pagination, consistent JSON
Auth	Plain passwords	JWT basics	bcrypt, middleware, roles
Errors	No handling	try/catch	Centralized, correct codes
Security	No awareness	CORS + validation	Helmet, rate limit, httpOnly

Homework: Implement one route from api-design.md from scratch in 15 minutes.