Scenario Based Questions

Definition

Interview questions that present a real-world problem and ask how you would architect a solution using Node.js.

Explain Like I'm New

These questions test your practical experience. Anyone can memorize definitions, but can you figure out why a server is crashing under load?

Real World Example

Scenario: 'Your Node app works perfectly for 10 users, but crashes completely when 10,000 users upload images at the exact same time. How do you fix it?'

Common Use Cases

•Mid-level to Senior interviews
•System design warm-ups

Interactive Example

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Interview Questions

basic

Scenario: You need to parse a 10GB CSV file in Node.js. How do you do it?

intermediate

Scenario: Your server is experiencing random 5-second freezes where it doesn't respond to any HTTP requests. What is likely causing this?

Flash Cards

Question

10GB CSV file?

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Answer

Use Streams. If you use `fs.readFile`, Node attempts to load all 10GB into RAM at once, crashing the V8 engine (which usually caps around 1.5GB). Using `fs.createReadStream` pipes the file chunk-by-chunk.

Question

5-second server freezes?

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Answer

You are blocking the Event Loop. Someone wrote a massive synchronous `for` loop, or used a synchronous crypto/JSON parsing function. Because Node is single-threaded, the entire server halts until that math finishes.