Ahhh, the classic "Hey we want to hire a junior dev with junior salary to re-build the entirety of Facebook from scratch by himself" interview. Love it. :D
React Reconciliation Algorithm: Previously, react used a synchronous stack compiler for reconciliation, which recursively worked it's way up the dom doing diff checking every re-render. The problem is that this can clog the event queue and lead to frame dropping. Now, with React Fiber, it can use interruptible rendering by assigning priority to certain elements. This gives us access to error boundaries and concurrency. In the case of a fiber tree, React doesn’t perform recursive traversal. Instead, it creates a singly-linked list and performs a parent-first, depth-first traversal.
I see things like this and am just grateful that I got my first developer position based on the fact that I had a good working knowledge of the internal software we use at a company I already worked for and could demonstrate that I was able to build a simple CRUD application to show that I could make a simple site that handled connecting to a database and showing/modifying data. I did another interview for a position that I ultimately ended up not accepting where the interview process was also very practically-based rather than technically based. Bottom line is that I think a lot of this stuff is fluff and the real questions should be based around how well you can solve problems and show you have enough of an understanding to make a simple working application for a Jr. Dev position.
I got put in charge of an entire automation system at my job, almost over night. I don't like the system but the new tasks beats the previous ones! Didn't even work with development at all before that, but had some private projects so I at least had the experience to get it up and runnning. Even rewrote a lot of their functionalities. (It's running AngularJS (Angular 1) as frontend and uses the browser as an IDE)
I had a interview for React JS Front End Dev position. The recruiter sent me a coding challenge. I thought it was related to front-end development but its more like medium to high level of algorithm . That coding challenge may affect my application. I love coding challenges but I haven't touched anything for months since I'm focus on learning in front-end development, react native and some python web scraping. I know algorithm is important but when I'm focused on something related to my job I tend to forgot some of the unrelated things.
don't let it discourage you. This was an interview just at one big company in India who probably has a very strange barrier of entry for their company. Not all interviews are like this.
12:55 "Who writes class components anymore". Lol at my last junior interview the guy loved class components so much that he didn't even know react hooks were a thing. He was convinced that class components could do things that functional components could not through inheritance.
This is really interesting. I tend to focus a lot on mindset, problem solving , communication, etc. than on minutia of a library when looking for engineers.
I think a good way to approach these types of, seemingly unnecessary questions, is asking the interviewer how it relates to the position you apply for. I know it can be difficult for a junior to know what's important and not, but if you have a slight concern about how a question applies, then ask. From my own experience, interviewers will either try to explain it in a way that is unrelated to the work, or flat out tell me that I'm right and move on to the next question. Interview processes should be about sharing knowledge, not about interrogating the interviewee. Some of these questions are fine, as long as they are outside the context of the position that you apply for, and shouldn't not determine whether or not they hire you.
I got my first FE dev job 5 months ago, so I had to go through this BS myself. The thing is web development market is quite crowded so companies are trying to get the best of best by asking these ridiculous questions even for an intern level position.
It's true, the market is super competitive so even low-level position has to be qualified, because they have so many options to choose from the pool, so they want to choose the best.
I think I may be starting to accept the fact that I can not get a dev job at this point. Every time there is something else to know. The list feels unending.
seems like it, I work with all senior devs basically, and I don't think any of them could explain the react reconciliation algorithm (or have bothered learning it). I think some of these questions are just unrelated to the actual job description. Maybe I'm just not a senior dev since I haven't learned this stuff.
You’re unique bc even though you have an actual CS degree and plenty of experience, you take a very practical/bootcampy approach towards building and explaining things. I feel like the industry gets lost in trying to make SWE something ethereal when in reality we are just building things just like any other tangible-object engineer does. I guess that’s the difference between CS and SWE.
Yeah, I could see that. I don’t recall most of anything i learned in computer science to transfer over to web dev. They didn’t even teach git or version control in my cs degree. Nothing in the degree was very practical
@@WebDevCody same here. Most everything I use day to day I learned on the job or on the side. I don't recommend people get a degree these days if they want to be a web dev.
I totally agree with your opinion on prototypes. I actually started hating them because I am a Freshman in College and we have to know every single thing about which is a 80 slide powerpoint.
I think the algorithm question just refers to "diffing." Being able to say "diffing" is easy, but being able to explain it is a bit more advanced (tree-traversals). I think the reason these questions are asked is because they are on the React tutorial and are the most obvious "trivia" questions. I personally think it's a good question because it helps you answer questions like, "Why should someone use React over x other framework?" Asking someone if they have thought about why they do what they do indicates to me how innately curious they are about their technology. I'd expect a junior to have at least heard of the term "diffing", and I'd expect a senior to have thought about how it might work. (And I'd only expect a lead React developer to know how it actually works.)
idk, I'm not a fan of "trivia" questions in general, but if you think some of those are useful, then I'll give you the benefit of the doubt. I've worked with maybe 10+ senior devs who code in react; I don't think a single one of them including myself know the diffing algorithm or could speak about it off the top of their head. Sure, it's a fun little thing to learn if you're into those things, but knowing the algorithm doesn't help solve real business problems.
@@WebDevCody I agree with you. I'm technically not a professional dev yet, so my opinions are from someone who is a new learner of React. So it could be something they only added recently to the docs. I'm not a fan of trivia either. I think how it works is that the interviewers don't think too much about the questions cuz they don't have time. They just look up a list of random React questions and ask them. I think this is more likely to happen when interviewing entry/junior devs who don't have previous projects to talk about. If you do have projects, it's better for the interviewee to pivot towards demoing their project. "You know what, I don't know what algorithm React uses. But I built a cool app with it, let me show you."
Oh, man. I've been "programming" for about a year (PowerPC assembly and some very barebones C) and I thought these were going to be the absolute minimum requirements for a potential job until you reinforced how advanced these questions are! I don't know what job I'm going to land on, but I hope to have programming as a backup plan.
Thats actually a good thing to happen. Easier to know for whom you should be working or not. If the interview for a junior role is like this, imagine the daily job. Horrendous
Ohhhh, I love interviews, especially with FANG companies. I remember having a phone interview with some a*hole from Amazon. He quite obviously had no technical expertise whatsoever, because one of his questions was, "if your server went offline, how would you bring it back online?". That's about as intelligent as asking, "if your car broke down on the highway, how would you fix it?". It's insane.
I can't find these junior dev jobs on linkedin - i've been applying to linkedin for months and i RARELY see any junior roles. any advice or other website?
Lol this happens all the time. I remember my first interview was for a bootstrap 3 ui dev position and they had a meme checklist like this for the questions. Now I ask right away how the question is directly relevant to this position I'm applying for. If they don't adjust I end the interview.
I misspoke, I've been coding for 4 years in react, but my opinion still remains. If learning about the algorithm used for reconciliation provides zero value to my day to day job, I don't care to learn about it. If knowing the algorithm becomes necessary, it's time to stop using react because the leaky abstraction has made the library garbage.
@@eveguelarocha9961 haha yeah sorry, I get defensive sometimes on youtube comments and throw a bit of attitude sometimes 🤣 thanks for watching my videos!
Coming from an interviewer side, at least at my company we have standard questions that we will ask every candidate regardless of their experience, specifically for the technical stuff we have questions in there we don't expect juniors to even know about but will throw in to gauge what level the candidate is in, and someone saying (I don't know what that is), isn't going to be a knock on any of those questions, but more impressive if they are able to answer what that is. I've even seen to some degree candidates get offered better positions at my company because they will ace a set of questions that we don't expect them to know about and have demonstrated a higher level of proficiency if those positions are available. So, I will say, if you don't know the answer to a question it is fine to say that you don't know. That isn't to say there are questions in an interview we do expect everyone to know about, but there are some things that you can only know more about through experience at a job.
yeah, I could see the benefit for doing something similar, but as long as it is made clear to the interviewee that "we do NOT expect you to know all of these questions", otherwise the candidate will just leave feeling defeated and probably consider your company as ridiculous. A lot of people fail interviews with no clue as to WHY they failed; these large companies do not tell candidates why they failed. They just get ghosted and we have no clue why.
@@WebDevCody I agree, ghosting really sucks, and is something every person I've seen at my place will go out of their way to explain to candidates exactly why their application wasn't chosen. They did so with me back when I applied as a junior fe developer, which actually then led them to encourage me to apply as a be engineer instead and land my job. Unfortunately a lot of places at least from what I've seen are really bad at interiewing candidates, and seem to try to hard to imitate big tech companies.
If I’m interviewing for a junior react position and I get the feeling a question is outside the scope of a junior dev, do I say that to the interviewer or just say I don’t know?
I'd just be respectful and say you don't know. I think it's worth asking for a "hint" if you think it's something you've learned in the past but forgot the name of the concept or something. I think if you tried to call them out and say "this is more like a senior position question" they might be offended lol.
I had an interview today which wasn’t really technical in the sense that you have to code but one question that stood out to me was how would you build out a link shortener for a website url. Other than that most questions I get as a person looking for internships is why you want to be a dev, why for us and just what you know. Other than that great video.
that is a cool question, it would test their understanding of maybe higher level design of a system, how your database tables might look like, how your API might look like. I might make a video on that ;). Yeah, usually it's more important to find if the person is eager and able to learn new things; that is much more important to quizzing them on how well they explain the definition to various topics in javascript or web dev.
"How can we prevent re rendering (without using useEffect, useMemo, useCallback). -> Class based components (PureComponent). Otherwise, just don't use states :D
I think in a lot of cases, the questions that seem like they're outside the scope of the specific position are probative questions to judge the FUTURE potential of a candidate. As a company/interviewer, if I ask only the questions to determine if a candidate is suitable for the open position, I leave the interview knowing only that one thing. But if I can ascertain their actual knowledge and skill level by asking more complicated/involved questions, that's good additional info I take from the interview.
yeah, I could see your argument to some extent. You want to push the boundaries of what they know and find out what they do not know. But I much rather probe in the direction of "what are some ways you'd verify your UI meets business requirements", or "what would you do if someone loaded up curl and hit your API with a million requests". Those actually tell me more about their knowledge about full stack engineering on a professional software project. Sure, I don't expect them to be able to explain everything about load balancing, rate limiting, DDOS attacks, etc, but it's more important to ask that than "how does the react reconciliation algorithm work".
"react uses something... and I dont need to know what that something is to build awesome websites" truth! amazing video man :) also have u checked out astro on your channel? I've been using it and I gotta say it feels like magic the way you can blend so many component libraries.
I haven't had a chance to check it out, I plan to start looking into remix soon honestly. Not enough time to learn them all, but people seem to like astro from what I hear.
6 years ago i was asked about hoisting on interview. I didn't knew. I was told i don't know beginner's answers such as hoisting. Today, after 6 years...i understand hoisting, but i have no idea how to use it, when to use it, why to use it and why people are still asking about that on the interviews
In Israel many startups ask this kind of answers because they expecting the frontend developer to be alot of things because the whole company consists of 10-25 ppl
Yeah they suck here in Israel, this is why i will learn and study alot, so I answer all these stupid questions, If anything, once I have a good position, i will try to change few things in the industry.
it's almost like these interviewers find a list of "good quiz questions" to ask people. This isn't school, why are we quizzing people on unrelated topics we don't use in our day to day job.
the way some of those questions are, it feels more like someone asked bunch of questions to get answers to prepare for interview rather than 'extracted' them from the interview. i never had that many questions/topics asked to begin with. especially that one part "how can we do, let's say in js?" sounds like it wasn't exactly js developer position..?
It would be great if you can give a self taught learning path for people who weren't able to get a degree to get to your skill level. Rn I'm a junior struggling to understand these concepts.
These are standard interview questions being asked here in China for devs fresh out of college. It's unnecessary but everyone just memorized it and companies have to keep raising the bar.
yeah, I don't get why they wouldn't just ask them to building something basic in the stack used at the company. A lot of these questions seem very unrelated to the job.
Look many times as an interviewer you get so excited by the candidate answering almost anything, you kind of get carried away. This happened to me many times. Of course in the end i would acknowledge that i kind of went beyond but tell him/her that he did well in this area and that area. So in my views questions asking beyond the role kind of gives the interviewer a view on how to project this interview feedbacks back to the HR or the Talent Acquisition team at the same time candidate can feel good about "see, there is tons to explore in the stack I am working on"
I would get mad at a Jr who knows all this :D. Letting the candidate build stuff like product filtering pages, card payment UI's with mock api's and validations, would be my way. I'd rather have a Jr who knows his way around the libraries we use, rather than hashmaps.
100%, like who really cares that much about hashes and hash maps? In javascript we just need to understand objects (which are basically maps) and how to use them.
If I got most of these questions, I would use the time to shit on React and how Solid and Svelte are better. Most of these questions are setup for that response anyway.
Thanks for sharing buddy. You mentioned at 4:35 that you've never hashed anything at work. Well in my opinion I think it's important to know in terms of how you keep passwords secure after registering a user. For example you must hash the user password using some sort of NPM package like bcryptjs or script that deals with this kind of thing. You can apply a pre middleware function that does this before saving the user to the database. Hope it helps :)
Yeah I’ve used hash at work for sure, I think I said “I haven’t had to use hash often”. It’s important for that example for sure, but I’d probably ask “explain your approach for storing passwords in a database” if I wanted to gauge their understanding of hash and security. Thanks for the comment!
@@WebDevCody Gotcha. Yeah some of these questions on the list are a bit confusing in my opinion and irrelevant to a junior. I don't think a Junior should be concerned about how the Virtual DOM works or optimization techniques like useMemo. I've been coding in React for about 3 years now and I still don't know 100% how the virtual DOM works. There's too much to learn. If I get asked a question in an interview I would just say like I don't know and I would just go on Google and figure out what the answer is. Much better than trying to BS your way through an interview. That's my opinion :)
In this day and age, I also wouldn't want to store passwords myself. I'd hand that over to some other authentication/authorization framework. Like Azure, Auth0, etc. Keeping user passwords is a liability I'm hesitant to traverse into.
The thing is, as far as I understood these were questions for a front end position. Hashing is really truly irrelevant in that case. Yeah maybe it's ok to know that hashing is used in security, but I wouldn't expect a junior frontend dev to know anything more about it, not even a name of a hashing algorithm or anything. It's not important in that position. What I would rather ask a front end developer is CSS specificity and what does cascade mean in CSS for example. Have they heard or used some CSS methodology like BEM for example. Have they tried any other framework than React etc. These questions shown in video all seem more focused on just Javascript like it's more for a Nodejs position, but then there are super specific React questions as well. If this was for a fullstack position I would understand some of these, but I wouldn't consider someone with 1 year of experience a fullstack capable dev really. To be honest, judging by all of this maybe the person looking for the job is lucky he didn't get the job there because it seems the interwiever is a wannabe elitist and potentially a person you don't want to work with.
@@rand0mtv660 it was for a junior full stack position; I think I forgot to mention that in the interview or said the wrong thing. So it helps with understanding more about some of the questions, but doesn't help that much. He said the company is one of the biggest companies in his region, so I'm assuming they have some generic questions to just weed out people.
Man I have roughly 6 years of experience (counting since I landed my first job) and I don't know answers to some of these questions and to be honest I didn't need to know answers to some of these so far. I do understand asking some of these questions and how they could lead to a technical discussion, but just the amount of questions and details some of these require feels like a college test if someone just memorized this stuff. I'm quite sure the interviewer asking these doesn't know a 100% correct answer for each of these. Some of these seem like they've been taken from some blog post titled "Top 50 React interview questions" lol
I agree as well, I've been coding in react for almost 4 years, and some of these questions I still don't know, but maybe thats ok the more I think about it. As long as the interviewer makes it kind of apparent that not knowing these answers is ok and it's more to gauge how much you know.
@@WebDevCody yeah you cannot know everything and you definitely don't need to know React reconcilliation algorithm to use React. That's just a React concept you can study if you are truly interested in internals. Yeah if interviewer is just judging your overall level and maybe just testing if you've even heard about some of these terms then ok, but I somehow doubt that's the case here. Too many weird questions for my taste and bunch of these aren't even frontend related. Also not a single HTML or CSS question at all which is weird for a frontend position.
@@rand0mtv660 yeah, I didn't think about that, no accessibility or styling questions at all. It was a junior full stack position; I don't think I mentioned that in the video or I said the wrong thing, so maybe that clears up a few things
I`m a web Developer with 1 Year of Vue and 4 Years of React JS ... and i know 8 out of how many lines u have in your videos ... So basicaly a medium-senior with nothing for a interview :))
I feel one needs to first know the insides of commonjs and the prototypes basics i.e understand how we can meta program objects using prototypes and object proxies. This is advance but usually people jump to building projects mostly from the youtube videos they watch online without considering why someone makes decisions on how they build applications and the benefits and shortcoming of their decisions. Personally I haven't landed a job yet but quite confident with JS. I feel we need to know how low level details are so that we may also be able to manipulate these tools and tweak them to our preference. JS is complicated indeed but still we can never master everything. The now recruiters require too much and making it hard for people to get into the industry. Thanks for the review. Ifeel now I have a good roadmap to learn reactjs. #codingforlife
I am a senior react developer, and tbh most of these questions dont even apply or even get implemented into a real life project. Sure, its good to know but then again how many times are you going to do prototypal inheritance in react? I know it wasnt asked but its as useless as asking that. Most things are abstracted away, and the only reason why you would dive into it is because of some weird race condition or someone wrote some jank ass code back in the day that you need to maintain.
Maybe I am alone with this but I like those questions. Of course, this is not junior level and when your job is to develop basic apps/UIs then probably 80% of those questions are not needed in real life, but if the interviewer is nice and willing to explain these concepts on the fly to help you out, then you might be able to learn a lot during these interviews. Also, I think it is important to remind people that webdev is not always just about rendering divs when a state changes.
The JS engine does not "achieve" (not sure what that means) async behavior. It handles the async stuff by giving it either to the Web API for the browser and Node API for node.js. The fact that this company is asking for other languages and how they handle async is total bs.
My bet is the interviewer googled some questions and made up a list. The questions are so bad and pretty much a cliche at this point. I’d rather give the interviewee a real problem in react if you really want to assess their ability and how they might help your company/team.
My guy, this is a red flag as I'm pretty sure you won't even deal with 95% of these "questions" once you get the job, like what's the point of talking about AES256 for example, why talking about hashing when there's a whole library that's doing all of the work to hash or encrypt passwords? doesn't make any sense..
no clue, but I'm hearing a lot of big companies do questions like this from India and China. It sounds like the leet code approach for MAANG. It's silly.
nah, not really. some of these are not common knowledge for even mid / senior developers. These questions really prove very little about the capabilities for the junior dev imo.
In India developers are expected to know everything thing even if they are Fresher..💔 Even I was asked abt the algorithm which react uses 🥲 Abt the sort method, we are asked in interviews to reverse an array without using inbuilt methods infact for every similar coding rounds we are asked to do without using any inbuilt methods..🥲 We should be independently can work and built it n can also deploy it..! 😅
Ahhh, the classic "Hey we want to hire a junior dev with junior salary to re-build the entirety of Facebook from scratch by himself" interview. Love it. :D
I was a senior front-end dev at Salesforce for nearly a decade, and I would have a really hard time with some of these interview questions lol.
I'm confident the senior devs were asking some of these questions because they genuinely didn't know.
In that case , be genuinely and you good for the next
🥲😅😅
React Reconciliation Algorithm:
Previously, react used a synchronous stack compiler for reconciliation, which recursively worked it's way up the dom doing diff checking every re-render. The problem is that this can clog the event queue and lead to frame dropping. Now, with React Fiber, it can use interruptible rendering by assigning priority to certain elements. This gives us access to error boundaries and concurrency.
In the case of a fiber tree, React doesn’t perform recursive traversal. Instead, it creates a singly-linked list and performs a parent-first, depth-first traversal.
thanks for the break down!
This is the kind of in depth React knowledge I'd look for from a Senior or Principal engineer 😅
@@MichaelChelen I'm looking for a job...
@@zombiefacesupreme bruh 🤣🤣
Thank you good sir for the in depth answer
I see things like this and am just grateful that I got my first developer position based on the fact that I had a good working knowledge of the internal software we use at a company I already worked for and could demonstrate that I was able to build a simple CRUD application to show that I could make a simple site that handled connecting to a database and showing/modifying data. I did another interview for a position that I ultimately ended up not accepting where the interview process was also very practically-based rather than technically based. Bottom line is that I think a lot of this stuff is fluff and the real questions should be based around how well you can solve problems and show you have enough of an understanding to make a simple working application for a Jr. Dev position.
yes I 100% agree
I got put in charge of an entire automation system at my job, almost over night. I don't like the system but the new tasks beats the previous ones!
Didn't even work with development at all before that, but had some private projects so I at least had the experience to get it up and runnning. Even rewrote a lot of their functionalities.
(It's running AngularJS (Angular 1) as frontend and uses the browser as an IDE)
I had a interview for React JS Front End Dev position. The recruiter sent me a coding challenge. I thought it was related to front-end development but its more like medium to high level of algorithm . That coding challenge may affect my application. I love coding challenges but I haven't touched anything for months since I'm focus on learning in front-end development, react native and some python web scraping. I know algorithm is important but when I'm focused on something related to my job I tend to forgot some of the unrelated things.
I think finding algorithms (for example, leet code) online is a lazy way to quiz developers.
A follow up video of "model answers" for the important/medium importance questions would be cool
that would be interesting
@@WebDevCody yeah looking forward to it!
This makes me feel like i will never be good enough to get a job
don't let it discourage you. This was an interview just at one big company in India who probably has a very strange barrier of entry for their company. Not all interviews are like this.
12:55 "Who writes class components anymore". Lol at my last junior interview the guy loved class components so much that he didn't even know react hooks were a thing. He was convinced that class components could do things that functional components could not through inheritance.
some people really like the OOP kool-aid
This is really interesting. I tend to focus a lot on mindset, problem solving , communication, etc. than on minutia of a library when looking for engineers.
probably the best approach honestly
yup someone's ability to break down a complex problem, or how they go about debugging an issue, is way more important than knowing a particular hook
I think a good way to approach these types of, seemingly unnecessary questions, is asking the interviewer how it relates to the position you apply for. I know it can be difficult for a junior to know what's important and not, but if you have a slight concern about how a question applies, then ask. From my own experience, interviewers will either try to explain it in a way that is unrelated to the work, or flat out tell me that I'm right and move on to the next question.
Interview processes should be about sharing knowledge, not about interrogating the interviewee. Some of these questions are fine, as long as they are outside the context of the position that you apply for, and shouldn't not determine whether or not they hire you.
I got my first FE dev job 5 months ago, so I had to go through this BS myself. The thing is web development market is quite crowded so companies are trying to get the best of best by asking these ridiculous questions even for an intern level position.
It's true, the market is super competitive so even low-level position has to be qualified, because they have so many options to choose from the pool, so they want to choose the best.
I think I may be starting to accept the fact that I can not get a dev job at this point. Every time there is something else to know. The list feels unending.
the list is unending, so find a company who understands that and hires based on willingness and ability to learn over hiring based on quiz questions.
Thank you! You are such a life saver.
thanks for this, now i'll spend like a day reading all about these topics and making sure i not only understand them but can articulate them properly
Sounds like they want a senior level guy for junior level pay
seems like it, I work with all senior devs basically, and I don't think any of them could explain the react reconciliation algorithm (or have bothered learning it). I think some of these questions are just unrelated to the actual job description. Maybe I'm just not a senior dev since I haven't learned this stuff.
Welcome to india my friend
@@WebDevCody exactly
hey man, just want to say really love the content and your live stream workings with code. I've been binge working through all your videos.
“Sort without using Sort.” You can’t make this stuff up. Im dead 💀💀
lol yeah I guess they wanted them to implement a custom sort method instead of using Array.prototype.sort.
They asked this many questions in an hour..?? I'd expect like 4 or 5 maybe. This is an exam!
You’re unique bc even though you have an actual CS degree and plenty of experience, you take a very practical/bootcampy approach towards building and explaining things. I feel like the industry gets lost in trying to make SWE something ethereal when in reality we are just building things just like any other tangible-object engineer does. I guess that’s the difference between CS and SWE.
Yeah, I could see that. I don’t recall most of anything i learned in computer science to transfer over to web dev. They didn’t even teach git or version control in my cs degree. Nothing in the degree was very practical
@@WebDevCody same here. Most everything I use day to day I learned on the job or on the side. I don't recommend people get a degree these days if they want to be a web dev.
Yeh I don't have any degree I learnt lot of thing in web dev
Cool. Screenshotted this list to use as a study guide.
I totally agree with your opinion on prototypes. I actually started hating them because I am a Freshman in College and we have to know every single thing about which is a 80 slide powerpoint.
I think the algorithm question just refers to "diffing." Being able to say "diffing" is easy, but being able to explain it is a bit more advanced (tree-traversals). I think the reason these questions are asked is because they are on the React tutorial and are the most obvious "trivia" questions. I personally think it's a good question because it helps you answer questions like, "Why should someone use React over x other framework?" Asking someone if they have thought about why they do what they do indicates to me how innately curious they are about their technology. I'd expect a junior to have at least heard of the term "diffing", and I'd expect a senior to have thought about how it might work. (And I'd only expect a lead React developer to know how it actually works.)
idk, I'm not a fan of "trivia" questions in general, but if you think some of those are useful, then I'll give you the benefit of the doubt. I've worked with maybe 10+ senior devs who code in react; I don't think a single one of them including myself know the diffing algorithm or could speak about it off the top of their head. Sure, it's a fun little thing to learn if you're into those things, but knowing the algorithm doesn't help solve real business problems.
@@WebDevCody I agree with you. I'm technically not a professional dev yet, so my opinions are from someone who is a new learner of React. So it could be something they only added recently to the docs. I'm not a fan of trivia either. I think how it works is that the interviewers don't think too much about the questions cuz they don't have time. They just look up a list of random React questions and ask them. I think this is more likely to happen when interviewing entry/junior devs who don't have previous projects to talk about. If you do have projects, it's better for the interviewee to pivot towards demoing their project. "You know what, I don't know what algorithm React uses. But I built a cool app with it, let me show you."
@@tbcfrankee yeah that makes sense to me. It's crazy how every company interviews so differently. There isn't any standard
Oh, man. I've been "programming" for about a year (PowerPC assembly and some very barebones C) and I thought these were going to be the absolute minimum requirements for a potential job until you reinforced how advanced these questions are! I don't know what job I'm going to land on, but I hope to have programming as a backup plan.
It’s also web dev, so your knowledge in c and powershell might not translate as well unless you find a windows specific devs ops role or something
Asking a junior dev how a framework works under the hood is actually asking them is they can make one.
We need more of these videos !
Thats actually a good thing to happen. Easier to know for whom you should be working or not.
If the interview for a junior role is like this, imagine the daily job. Horrendous
Ohhhh, I love interviews, especially with FANG companies. I remember having a phone interview with some a*hole from Amazon. He quite obviously had no technical expertise whatsoever, because one of his questions was, "if your server went offline, how would you bring it back online?". That's about as intelligent as asking, "if your car broke down on the highway, how would you fix it?". It's insane.
Thanks for sharing this. I found it to be very helpful.
I can't find these junior dev jobs on linkedin - i've been applying to linkedin for months and i RARELY see any junior roles. any advice or other website?
I'm not too sure to be honest, I'm out of touch with the whole hiring part of things
When senior ego interviews a junior, unreal
Lol this happens all the time. I remember my first interview was for a bootstrap 3 ui dev position and they had a meme checklist like this for the questions. Now I ask right away how the question is directly relevant to this position I'm applying for. If they don't adjust I end the interview.
"If i've been coding for react for like 7 years and I don't know it, then obviously I don't need to know it"
Sheesh
I misspoke, I've been coding for 4 years in react, but my opinion still remains. If learning about the algorithm used for reconciliation provides zero value to my day to day job, I don't care to learn about it. If knowing the algorithm becomes necessary, it's time to stop using react because the leaky abstraction has made the library garbage.
@@WebDevCody You have a great point actually, I like that way you answer them, It's has attitude but not in arrogant way
@@eveguelarocha9961 haha yeah sorry, I get defensive sometimes on youtube comments and throw a bit of attitude sometimes 🤣 thanks for watching my videos!
@@WebDevCody will watch for more! 🙌
More of these and thanks 🙂
love these kinds of videos
This is a non-developers choice of interview questions :D
Coming from an interviewer side, at least at my company we have standard questions that we will ask every candidate regardless of their experience, specifically for the technical stuff we have questions in there we don't expect juniors to even know about but will throw in to gauge what level the candidate is in, and someone saying (I don't know what that is), isn't going to be a knock on any of those questions, but more impressive if they are able to answer what that is. I've even seen to some degree candidates get offered better positions at my company because they will ace a set of questions that we don't expect them to know about and have demonstrated a higher level of proficiency if those positions are available.
So, I will say, if you don't know the answer to a question it is fine to say that you don't know. That isn't to say there are questions in an interview we do expect everyone to know about, but there are some things that you can only know more about through experience at a job.
yeah, I could see the benefit for doing something similar, but as long as it is made clear to the interviewee that "we do NOT expect you to know all of these questions", otherwise the candidate will just leave feeling defeated and probably consider your company as ridiculous. A lot of people fail interviews with no clue as to WHY they failed; these large companies do not tell candidates why they failed. They just get ghosted and we have no clue why.
@@WebDevCody I agree, ghosting really sucks, and is something every person I've seen at my place will go out of their way to explain to candidates exactly why their application wasn't chosen. They did so with me back when I applied as a junior fe developer, which actually then led them to encourage me to apply as a be engineer instead and land my job. Unfortunately a lot of places at least from what I've seen are really bad at interiewing candidates, and seem to try to hard to imitate big tech companies.
If I’m interviewing for a junior react position and I get the feeling a question is outside the scope of a junior dev, do I say that to the interviewer or just say I don’t know?
I'd just be respectful and say you don't know. I think it's worth asking for a "hint" if you think it's something you've learned in the past but forgot the name of the concept or something. I think if you tried to call them out and say "this is more like a senior position question" they might be offended lol.
I had an interview today which wasn’t really technical in the sense that you have to code but one question that stood out to me was how would you build out a link shortener for a website url. Other than that most questions I get as a person looking for internships is why you want to be a dev, why for us and just what you know. Other than that great video.
that is a cool question, it would test their understanding of maybe higher level design of a system, how your database tables might look like, how your API might look like. I might make a video on that ;). Yeah, usually it's more important to find if the person is eager and able to learn new things; that is much more important to quizzing them on how well they explain the definition to various topics in javascript or web dev.
@@splinestein it's definitely full stack, and open ended enough that there could be multiple approaches which makes for interesting questions
"How can we prevent re rendering (without using useEffect, useMemo, useCallback). -> Class based components (PureComponent). Otherwise, just don't use states :D
I think in a lot of cases, the questions that seem like they're outside the scope of the specific position are probative questions to judge the FUTURE potential of a candidate. As a company/interviewer, if I ask only the questions to determine if a candidate is suitable for the open position, I leave the interview knowing only that one thing. But if I can ascertain their actual knowledge and skill level by asking more complicated/involved questions, that's good additional info I take from the interview.
yeah, I could see your argument to some extent. You want to push the boundaries of what they know and find out what they do not know. But I much rather probe in the direction of "what are some ways you'd verify your UI meets business requirements", or "what would you do if someone loaded up curl and hit your API with a million requests". Those actually tell me more about their knowledge about full stack engineering on a professional software project. Sure, I don't expect them to be able to explain everything about load balancing, rate limiting, DDOS attacks, etc, but it's more important to ask that than "how does the react reconciliation algorithm work".
pretty sure interviewers are seniors and have like 10 years of experience in industry will ask practical questions than these one.
if I told you that your channel is the best will you believe me?
keep going man we love your content
ty!
"react uses something... and I dont need to know what that something is to build awesome websites" truth! amazing video man :) also have u checked out astro on your channel? I've been using it and I gotta say it feels like magic the way you can blend so many component libraries.
I haven't had a chance to check it out, I plan to start looking into remix soon honestly. Not enough time to learn them all, but people seem to like astro from what I hear.
6 years ago i was asked about hoisting on interview. I didn't knew. I was told i don't know beginner's answers such as hoisting. Today, after 6 years...i understand hoisting, but i have no idea how to use it, when to use it, why to use it and why people are still asking about that on the interviews
In Israel many startups ask this kind of answers because they expecting the frontend developer to be alot of things because the whole company consists of 10-25 ppl
Yeah they suck here in Israel, this is why i will learn and study alot, so I answer all these stupid questions,
If anything, once I have a good position, i will try to change few things in the industry.
it's almost like these interviewers find a list of "good quiz questions" to ask people. This isn't school, why are we quizzing people on unrelated topics we don't use in our day to day job.
Looks like they want the junior to work a framework they are building🙃
the way some of those questions are, it feels more like someone asked bunch of questions to get answers to prepare for interview rather than 'extracted' them from the interview.
i never had that many questions/topics asked to begin with. especially that one part "how can we do, let's say in js?" sounds like it wasn't exactly js developer position..?
it was a junior full stack position; he said the interview lasted an hour, and that was only for the first round of the interview.
It would be great if you can give a self taught learning path for people who weren't able to get a degree to get to your skill level. Rn I'm a junior struggling to understand these concepts.
These are standard interview questions being asked here in China for devs fresh out of college. It's unnecessary but everyone just memorized it and companies have to keep raising the bar.
yeah, I don't get why they wouldn't just ask them to building something basic in the stack used at the company. A lot of these questions seem very unrelated to the job.
LETS PLAY FOOTBALL
Look many times as an interviewer you get so excited by the candidate answering almost anything, you kind of get carried away.
This happened to me many times. Of course in the end i would acknowledge that i kind of went beyond but tell him/her that he did well in this area and that area.
So in my views questions asking beyond the role kind of gives the interviewer a view on how to project this interview feedbacks back to the HR or the Talent Acquisition team at the same time candidate can feel good about "see, there is tons to explore in the stack I am working on"
yeah that makes sense, it's good to push the boundaries to find out how much they actually know
I would get mad at a Jr who knows all this :D. Letting the candidate build stuff like product filtering pages, card payment UI's with mock api's and validations, would be my way. I'd rather have a Jr who knows his way around the libraries we use, rather than hashmaps.
100%, like who really cares that much about hashes and hash maps? In javascript we just need to understand objects (which are basically maps) and how to use them.
I am from India . I watched your videos . I like your content
KEEP IT UP BRO
If I got most of these questions, I would use the time to shit on React and how Solid and Svelte are better. Most of these questions are setup for that response anyway.
The interviewer from India , I wonder what was the package. High chance they also offered low package with this in-depth questions. 😂
Thanks for sharing buddy. You mentioned at 4:35 that you've never hashed anything at work. Well in my opinion I think it's important to know in terms of how you keep passwords secure after registering a user. For example you must hash the user password using some sort of NPM package like bcryptjs or script that deals with this kind of thing. You can apply a pre middleware function that does this before saving the user to the database. Hope it helps :)
Yeah I’ve used hash at work for sure, I think I said “I haven’t had to use hash often”. It’s important for that example for sure, but I’d probably ask “explain your approach for storing passwords in a database” if I wanted to gauge their understanding of hash and security. Thanks for the comment!
@@WebDevCody Gotcha. Yeah some of these questions on the list are a bit confusing in my opinion and irrelevant to a junior. I don't think a Junior should be concerned about how the Virtual DOM works or optimization techniques like useMemo. I've been coding in React for about 3 years now and I still don't know 100% how the virtual DOM works. There's too much to learn. If I get asked a question in an interview I would just say like I don't know and I would just go on Google and figure out what the answer is. Much better than trying to BS your way through an interview. That's my opinion :)
In this day and age, I also wouldn't want to store passwords myself. I'd hand that over to some other authentication/authorization framework. Like Azure, Auth0, etc. Keeping user passwords is a liability I'm hesitant to traverse into.
The thing is, as far as I understood these were questions for a front end position. Hashing is really truly irrelevant in that case. Yeah maybe it's ok to know that hashing is used in security, but I wouldn't expect a junior frontend dev to know anything more about it, not even a name of a hashing algorithm or anything. It's not important in that position. What I would rather ask a front end developer is CSS specificity and what does cascade mean in CSS for example. Have they heard or used some CSS methodology like BEM for example. Have they tried any other framework than React etc. These questions shown in video all seem more focused on just Javascript like it's more for a Nodejs position, but then there are super specific React questions as well. If this was for a fullstack position I would understand some of these, but I wouldn't consider someone with 1 year of experience a fullstack capable dev really. To be honest, judging by all of this maybe the person looking for the job is lucky he didn't get the job there because it seems the interwiever is a wannabe elitist and potentially a person you don't want to work with.
@@rand0mtv660 it was for a junior full stack position; I think I forgot to mention that in the interview or said the wrong thing. So it helps with understanding more about some of the questions, but doesn't help that much. He said the company is one of the biggest companies in his region, so I'm assuming they have some generic questions to just weed out people.
Good job babe!!!
Man I have roughly 6 years of experience (counting since I landed my first job) and I don't know answers to some of these questions and to be honest I didn't need to know answers to some of these so far. I do understand asking some of these questions and how they could lead to a technical discussion, but just the amount of questions and details some of these require feels like a college test if someone just memorized this stuff. I'm quite sure the interviewer asking these doesn't know a 100% correct answer for each of these. Some of these seem like they've been taken from some blog post titled "Top 50 React interview questions" lol
I agree as well, I've been coding in react for almost 4 years, and some of these questions I still don't know, but maybe thats ok the more I think about it. As long as the interviewer makes it kind of apparent that not knowing these answers is ok and it's more to gauge how much you know.
@@WebDevCody yeah you cannot know everything and you definitely don't need to know React reconcilliation algorithm to use React. That's just a React concept you can study if you are truly interested in internals.
Yeah if interviewer is just judging your overall level and maybe just testing if you've even heard about some of these terms then ok, but I somehow doubt that's the case here. Too many weird questions for my taste and bunch of these aren't even frontend related. Also not a single HTML or CSS question at all which is weird for a frontend position.
@@rand0mtv660 yeah, I didn't think about that, no accessibility or styling questions at all. It was a junior full stack position; I don't think I mentioned that in the video or I said the wrong thing, so maybe that clears up a few things
Makes me think of the questions I just got from Activision. Most of them were easily SE3-SE5 questions.
I`m a web Developer with 1 Year of Vue and 4 Years of React JS ... and i know 8 out of how many lines u have in your videos ...
So basicaly a medium-senior with nothing for a interview :))
yeah, some of these are silly to ask.
I feel one needs to first know the insides of commonjs and the prototypes basics i.e understand how we can meta program objects using prototypes and object proxies. This is advance but usually people jump to building projects mostly from the youtube videos they watch online without considering why someone makes decisions on how they build applications and the benefits and shortcoming of their decisions. Personally I haven't landed a job yet but quite confident with JS. I feel we need to know how low level details are so that we may also be able to manipulate these tools and tweak them to our preference. JS is complicated indeed but still we can never master everything. The now recruiters require too much and making it hard for people to get into the industry. Thanks for the review. Ifeel now I have a good roadmap to learn reactjs. #codingforlife
I am a senior react developer, and tbh most of these questions dont even apply or even get implemented into a real life project. Sure, its good to know but then again how many times are you going to do prototypal inheritance in react? I know it wasnt asked but its as useless as asking that. Most things are abstracted away, and the only reason why you would dive into it is because of some weird race condition or someone wrote some jank ass code back in the day that you need to maintain.
Maybe I am alone with this but I like those questions. Of course, this is not junior level and when your job is to develop basic apps/UIs then probably 80% of those questions are not needed in real life, but if the interviewer is nice and willing to explain these concepts on the fly to help you out, then you might be able to learn a lot during these interviews. Also, I think it is important to remind people that webdev is not always just about rendering divs when a state changes.
The JS engine does not "achieve" (not sure what that means) async behavior. It handles the async stuff by giving it either to the Web API for the browser and Node API for node.js. The fact that this company is asking for other languages and how they handle async is total bs.
These are Junior Questions???
apparently they were for a junior full stack position
Okay so I can answer about 70% of these questions. Am I ready for junior level job interview?
My bet is the interviewer googled some questions and made up a list. The questions are so bad and pretty much a cliche at this point. I’d rather give the interviewee a real problem in react if you really want to assess their ability and how they might help your company/team.
Nobody knows license and legal
I'm a higher level
My guy, this is a red flag as I'm pretty sure you won't even deal with 95% of these "questions" once you get the job, like what's the point of talking about AES256 for example, why talking about hashing when there's a whole library that's doing all of the work to hash or encrypt passwords? doesn't make any sense..
no clue, but I'm hearing a lot of big companies do questions like this from India and China. It sounds like the leet code approach for MAANG. It's silly.
soydev
very easy questions
nice ego
nah, not really. some of these are not common knowledge for even mid / senior developers. These questions really prove very little about the capabilities for the junior dev imo.
In India developers are expected to know everything thing even if they are Fresher..💔
Even I was asked abt the algorithm which react uses 🥲
Abt the sort method, we are asked in interviews to reverse an array without using inbuilt methods infact for every similar coding rounds we are asked to do without using any inbuilt methods..🥲
We should be independently can work and built it n can also deploy it..! 😅
Did this guy play Daniel Jackson in the original Stargate movie? ʲᵘˢᵗ ʲᵒᵏᶦⁿᵍ