| 1 | How does Node's node:https module differ from node:http, and what additional configuration does it require? Node.js › HTTP & HTTPS Modules | Node.js | HTTP & HTTPS Modules | Intermediate |
| 2 | How would you create a basic HTTP server using only Node's built-in node:http module, without a framework like Express? Node.js › HTTP & HTTPS Modules | Node.js | HTTP & HTTPS Modules | Beginner |
| 3 | How would you make an outgoing HTTP request from Node.js using the built-in fetch API versus the older http.request()? Node.js › HTTP & HTTPS Modules | Node.js | HTTP & HTTPS Modules | Advanced |
| 4 | What is HTTP keep-alive, and how does Node's http.Agent manage connection reuse for outgoing requests? Node.js › HTTP & HTTPS Modules | Node.js | HTTP & HTTPS Modules | Intermediate |
| 5 | How would you implement HTTP/2 server push or basic HTTP/2 support in Node.js using the node:http2 module? Node.js › HTTP & HTTPS Modules | Node.js | HTTP & HTTPS Modules | Advanced |
| 6 | What does the node:zlib module provide, and how would you use it to compress an HTTP response? Node.js › Core Node.js Modules | Node.js | Core Node.js Modules | Intermediate |
| 7 | What does the URL/URLSearchParams API provide, and why is it generally preferred over the older querystring module today? Node.js › Core Node.js Modules | Node.js | Core Node.js Modules | Beginner |
| 8 | What is the difference between storing an authentication token in localStorage versus an httpOnly cookie, from a security perspective? Node.js › Authentication & Authorization | Node.js | Authentication & Authorization | Beginner |
| 9 | What is Express.js, and what problem does it solve compared to using Node.js's raw http module directly? Node.js › Express & Middleware | Node.js | Express & Middleware | Beginner |
| 10 | What HTTP caching headers (Cache-Control, ETag) can a Node.js/Express API use to let clients and CDNs cache responses? Node.js › Caching | Node.js | Caching | Intermediate |
| 11 | What is the difference between res.set('Cache-Control', 'no-cache') and 'no-store' in an Express response? Node.js › Caching | Node.js | Caching | Beginner |
| 12 | What does the EXPOSE instruction in a Dockerfile actually do, and what is a common misconception about it? Node.js › Docker & Deployment | Node.js | Docker & Deployment | Beginner |
| 13 | What is Nodemailer, and how does it let a Node.js application send emails via SMTP? Node.js › Email & Notifications | Node.js | Email & Notifications | Beginner |
| 14 | What is the difference between the 'to', 'cc', and 'bcc' fields when sending an email programmatically, and why does 'bcc' matter for privacy? Node.js › Email & Notifications | Node.js | Email & Notifications | Beginner |
| 15 | What is the purpose of the express.static() built-in middleware, and how would you use it to serve a folder of static assets? Node.js › Express & Middleware | Node.js | Express & Middleware | Beginner |
| 16 | What is the risk of caching sensitive or user-specific data with a shared cache key, and how do you avoid it? Node.js › Caching | Node.js | Caching | Intermediate |
| 17 | What is a load balancer, and how does it distribute traffic across multiple Node.js application instances? Node.js › Cloud & DevOps | Node.js | Cloud & DevOps | Intermediate |
| 18 | What is a reverse proxy, and why is Nginx commonly placed in front of a Node.js application in production? Node.js › Cloud & DevOps | Node.js | Cloud & DevOps | Intermediate |
| 19 | What is the difference between the 'sticky' and default load-balancing strategies when using Node's cluster module, and when does it matter? Node.js › Clustering & Worker Threads | Node.js | Clustering & Worker Threads | Intermediate |
| 20 | How would you send a push notification from a Node.js backend to a mobile app using Firebase Cloud Messaging (FCM)? Node.js › Email & Notifications | Node.js | Email & Notifications | Intermediate |
| 21 | What is the difference between transactional email and marketing email, and why do most Node.js applications use separate providers or sending domains for each? Node.js › Email & Notifications | Node.js | Email & Notifications | Intermediate |
| 22 | What is the difference between sending SMS via a provider's REST API (like Twilio) versus using SMTP-based email in terms of a Node.js integration? Node.js › Email & Notifications | Node.js | Email & Notifications | Intermediate |
| 23 | What does the express.json() and express.urlencoded() built-in middleware do, and why must it be registered before routes that need to read req.body? Node.js › Express & Middleware | Node.js | Express & Middleware | Intermediate |
| 24 | What is the purpose of the helmet middleware package for an Express application, and what specific security headers does it set? Node.js › Express & Middleware | Node.js | Express & Middleware | Intermediate |
| 25 | What is CORS middleware in Express, and how does the cors package simplify configuring Cross-Origin Resource Sharing? Node.js › Express & Middleware | Node.js | Express & Middleware | Intermediate |
| 26 | How would you implement a simple rate limiter using Redis's INCR command with expiration? Node.js › Caching with Redis | Node.js | Caching with Redis | Intermediate |
| 27 | How would you implement API key authentication for a Node.js service consumed by other backend services, and what are its security limitations? Node.js › Authentication & Authorization | Node.js | Authentication & Authorization | Advanced |
| 28 | How do you implement rate-limited job processing so a Node.js worker doesn't exceed a downstream third-party API's request limits? Node.js › Background Jobs & Queues | Node.js | Background Jobs & Queues | Advanced |
| 29 | What is the 'stale-while-revalidate' caching strategy, and how would you implement it for an API response? Node.js › Caching | Node.js | Caching | Advanced |
| 30 | What are SPF, DKIM, and DMARC, and why do they matter for a Node.js application's transactional emails actually reaching users' inboxes? Node.js › Email & Notifications | Node.js | Email & Notifications | Advanced |
| 31 | What is token introspection, and when is it needed instead of simply verifying a JWT's signature locally? Node.js › Authentication & Authorization (JWT, OAuth, Passport) | Node.js | Authentication & Authorization (JWT, OAuth, Passport) | Advanced |
| 32 | What is PKCE (Proof Key for Code Exchange), and why is it now recommended for OAuth flows even in traditional server-side Node.js applications? Node.js › Authentication & Authorization (JWT, OAuth, Passport) | Node.js | Authentication & Authorization (JWT, OAuth, Passport) | Advanced |