Entry

Q1: What is Node.js?
Q2: What is npm?
Q3: What are the two types of API functions in Node.js?

Junior

Q4: What do you mean by Asynchronous API?
Q5: What are the benefits of using Node.js?
Q6: Is Node a single threaded application?
Q7: What is global installation of dependencies?
Q8: What is an error-first callback?
Q9: What’s the difference between operational and programmer errors?
Q10: What is the difference between Nodejs, AJAX, and jQuery?
Q11: How to make Post request in Node.js?
Q12: How you can monitor a file for modifications in Node.js ?
Q13: What is control flow function?
Q14: What are Event Listeners?
Q15: If Node.js is single threaded then how it handles concurrency?
Q16: What is Callback Hell?
Q17: List out the differences between AngularJS and NodeJS?
Q18: Could we run an external process with Node.js?
Q19: What are the core modules of Node.js?
Q20: What is V8?
Q21: What is libuv?
Q22: What is the difference between returning a callback and just calling a callback?
Q23: What are the key features of Node.js?

Mid

Q24: What is REPL in context of Node?
Q25: What is Callback?
Q26: How Node prevents blocking code?
Q27: What is Event Loop?
Q28: What is Event Emmitter?
Q29: What is purpose of Buffer class in Node?
Q30: What is difference between synchronous and asynchronous method of fs module?
Q31: What are streams?
Q32: What is Chaining in Node?
Q33: What is the purpose of setTimeout function?
Q34: How can you avoid callback hells?
Q35: How to avoid callback hell in Node.js?
Q36: Explain how does Node.js work?
Q37: When should we use Node.js?
Q38: How does Node.js handle child threads?
Q39: What is the preferred method of resolving unhandled exceptions in Node.js?
Q40: What is stream and what are types of streams available in Node.js?
Q41: What are the global objects of Node.js?
Q42: When should I use EventEmitter?
Q43: How do you debug Node.js applications?
Q44: Rewrite promise-based Node.js applications to Async/Await
Q45: What is the relationship between Node.js and V8?
Q46: What is N-API in Node.js?
Q47: Explain the concept of Domain in Node.js
Q48: What are the use cases for the Node.js “vm” core module?
Q49: What is a blocking code?
Q50: What’s the event loop?
Q51: How to use Buffer in Node.js?
Q52: Are you familiar with differences between Node.js modules and ES6 modules?

Senior

Q53: What is Piping in Node?
Q54: Name some of the events fired by streams.
Q55: What is the purpose of __filename variable?
Q56: How can you listen on port 80 with Node?
Q57: What tools can be used to assure consistent code style?
Q58: What’s a stub?
Q59: Does Node.js support multi-core platforms?
Q60: Is Node.js entirely based on a single-thread?
Q61: Is Node.js entirely based on a single-thread?
Q62: When to not use Node.js?
Q63: Why to use Buffers instead of binary strings to handle binary data ?
Q64: How to gracefully Shutdown Node.js Server?
Q65: What are the timing features of Node.js?
Q66: Explain usage of NODE_ENV
Q67: What is LTS releases of Node.js why should you care?
Q68: Provide some example of config file separation for dev and prod environments
Q69: How would you handle errors for async code in Node.js?
Q70: What’s the difference between dependencies, devDependencies and peerDependencies in npm package.json file?
Q71: How do you convert an existing callback API to promises?
Q72: What are async functions in Node?
Q73: Can Node.js work without V8?
Q74: How the V8 engine works?
Q75: How does the cluster module work?
Q76: Is it possible to use “Class” in Node.js?

Expert

Q77: Can Node.js use other engines than V8?
Q78: Consider following code snippet

{
  console.time("loop");
  for (var i = 0; i < 1000000; i += 1) {
    // Do nothing
  }
  console.timeEnd("loop");
}

Q79: How would you scale Node application?
Q80: What is the difference between process.nextTick() and setImmediate() ?
Q81: How to solve “Process out of Memory Exception” in Node.js ?
Q82: Explain what is Reactor Pattern in Node.js?
Q83: Explain some Error Handling approaches in Node.js you know about. Which one will you use?
Q84: Why should you separate Express ‘app’ and ‘server’?
Q85: Rewrite the code sample without try/catch block

async function check(req, res) {
  try {
    const a = await someOtherFunction();
    const b = await somethingElseFunction();
    res.send("result")
  } catch (error) {
    res.send(error.stack);
  }
}

Q86: How many threads does Node actually create?
Q87: What is the purpose of using hidden classes in V8?
Q88: How V8 compiles JavaScript code?
Q89: How does libuv work under the hood?
Q90: What is V8 Templates?
Q91: Why do we need C++ Addons in Node.js?
Q92: Why Node.js devs tend to lean towards the Module Requiring vs Dependency Injection?
Q93: What will happen when that code will be executed?