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Thank you so much for these videos. It's so awesome that you are thinking and talking through the options available for each section in your plan!

7:09 shouldn’t be a boolean?

You can omit the Error suffix from the Error cases as the fact that it is error will be stated by the enum name

After being an Engendering Manager and a Lead Developer at Meta, what else can you strive for? Or in other words, what would you like to do in 5-10 years?

That’s just amazing!! How did you get to this level of crisp and clear articulation of your thought?

Regarding the API implementation: Is there a need for an escaping completion block nower days? I could just return the Result<,> and make the function async. Correct?

And do you have a LinkedIn? I would love to follow your journey

Hello yet again, In one of your videos you mentioned that you didn’t develop native iOS in Meta? Didn’t it create discomfort knowing that you are staying behind on the native technology (it turned out impactful for the Uber interview) or was the fact that it is Meta, made it bearable? 😅

Hey again Andrey :) What was the contributing factors for you becoming an Engineering Manager. And why didn’t you continue with the managerial trajectory?

Hey Andrey, you made few videos about solving LeetCode questions. What was your objective doing LeetCode as an iOS developer?

You rock man!!!! What a wonderful video!

Can you share some details on why you decided to leave meta? Thanks for the great content - it´s really inspiring and entertaining. :)

why is it important how many users will be using the app at the same time? How does such metrics affect a client side app?

nice breakdown Andrey. thanks.

Hi @Andrey Please cover topic that are related to creating a mobile SDK , Design Payment SDK Design Network SDK Design Analytics SDK Design Image cache SDK Design File Downloader SDK the reason I am saying these topic because these topics require more focus on architecting instead of simply following MVVM because there is no UI layer involved into these topic

Very nice.

Sounds good.

Man, thank you for sharing your experience. You make great content. Keep it up

Next week I'll have my on site interview at Meta. Your videos about system design are really great. Let's see how it goes 😬

hey @andrey you break the overall process nicely. I really appreciate you work.

How to do it in 2024?? Can it be done in month or 2 jus for project

Thanks for the content. As a self-taught developer, how did you learn app architecture and computer basic courses such as operating systems and computer networks?

SOA? are you talking about SOA-like modules where modules provide functionality as opposed to a monolithic app?, thanks for the info :)

Great & simple explanation. Thanks

Say hi to Swift, say bye to Objective-C ❤️

Artificial Intelligence 😊

Inspiring journey!

I think there is a good reason why there is no real cache in Instagram, post can be deleted, likes can be added, or removed. the cache thing is just a "psychological" UX lie )), there actually only about 3-5? last post cached, the like offline option, is more for online error happened thing, then for "offline like", but as most probably, from implementation side, you can cover both the same... you have this option, but you are the one who work in Facebook (so you can tell us, if i am wrong))) . ps, for this simple up, when only so basic usage of db is needed, maybe core-data, or plain SQL is ok, but for something more complex, i would go with realm, any day of the week. Have no opinion about the new swift-data thing, have not used it yet, but core data has really poor performance for anything complex, realm is way more effective, with its lazy loading model. (fetchBatchSize, is not really lazy loading). you make all those record, about designs, but you never mentions how did the interviewer tackled your design, about some "disagreements", and places, where you had polity defend you ideas...

funny real Instagram app actually has this like offline option (never knew). the "cache" function is very limited though... i can only see very last few posts, so it kind of funny they bothered implementing this "like offline" ))). regarding pagination being naive, this is not true. on mobile side, both are implemented with same "ease", both approaches have there use cases, when you loop videos on you-tube search api, or flickr images search, there is no point what so ever for "cache", and when cache of network calls is not needed, there is no point in "timestamps", so it not that is is "naive", it just dont suite for cache post history, on the other hand "timestamp" approach, will not feet flickr api. or any api, that dont need cache for that matter.

no no )))) just return is bad... ))) return the error to the closer ) (2,24), also u should check the response code aka 200, when you use network call which throws(it is a must), yet, it good practice to check even in this case, you never know... maybe you cloud side friend decides it is a good idea return error, with error code 299 ))) you explain very nicely how to answer this type of quotations, I do have the knowledge, but luck skills of presentation, so thanks )

dude stop maintaining silent push )), it is totally unrelated to what user needs, delivery time is something, undocumented, even if the app in foreground. silent pushes, is nice tool for pushing something not very important, or argent.

Thanks!

awesome video. I really like how you gave reasoning for cursor based pagination. nit: its not "i mage" it is "image" sounds something like 'emage'

very nice video

Quick question, for storing metadata, why do we need to choose a framework specifically for managing object graphs?

Principal software engineer here with 40 years + experience. In my experience, there's 3 types of technical interviews: 1. They want to know what you can do and how you think. This is the one you can pass. People are usually friendly and encourage you. 2. They want to know if you do things the way they do things. This is hard to pass and they'll often be rude. You don't do things like they do so you suck and they want you to know it. 3. They want to know what you cannot do (the opposite of 1). What you are good at is not interesting, they want to know what you suck at (in their opinion). The interview is focused on this. As soon as you seem to know what you are doing/talking about, they want to move to something else. They will be rude and will fail you. It's unlikely to pass 2 and 3. I once interviewed for a position with no DB experience required. Interview was of type 3. I nailed every question and exercise so the guy started to ask about DB queries (again DB not required for position). What's the query if you want to do this or that? I nailed most of them until he finally found one query question where I wasn't too sure. You could clearly see how happy that made him so he could finally fail me. With more experience now, when I feel this is a type 3 interview, I just start failing every question on purpose cos nothing good comes out of those interviews and I avoid stress I don't need.

How can I contact you sir please 🙏

How can I contact you sir

Please reply sir

Hi

I have a interview this Thursday wish me luck it’s my first job ha no experience

Great videos as always. A question I had for anyone in the comments or @AndreyTech himself. I'm failing to see the need for Core Data in this architecture, and any long term persistence. We fetch restaurants, images, etc. Generally, this type of app is used by a user for 15 tops type thing, and then not again for usually at least say 24 hours if they order a meal again the next day. That next day, we're going to need to fetch restaurants and meals again. Prices can change, restaurants may be closed as it's Sunday, if you change your address any restaurant we previously knew about may no longer be in the delivery zone etc. I think NSURLCache would suffice here for all our meta data. Likely don't need to init it with any disk size capacity, just memory. Images could be via SDWebImage or a simple ImageService based off NSCache once again just utilizing memory and no need for long term persistence. My only critique of the architecture after watching is the use of CoreData. I think it's overhead for this particular example that offers no benefit. Just my 2 cents! Wonderful video as always, your System Design videos are great. Keep them up!

I recently had an initial interview with one of their "head of.." and it was the most unprofessional and unpleasant call I have ever experienced. He was 15 minutes late (I almost canceled the call) without offering an apology, asked a lot of silly questions to which I provided examples, and he yawned throughout, giving off an impression of disinterest in hiring anyone. It seemed like they may have conducted the interview just to fulfill their internal recruitment procedures. If this is the representation of the company, I can't think the level of toxicity within.

sound seems lower..

Hey Andrey - I sent you an email about a paid partnership. Let me know what you think.

Thanks fot this video. Do tou have any recommendations for ios system design preparation? Usually the content out there is more focused on backend

Great video! 1. Why do we need user-id in API requests? Backend already knows client's identity. (from access token) 2. In payload, why do we send postID to server? We already send "page" for pagination. 3. On 10:27, what do you mean by "user unloads app from memory and loads it back?". You mean navigating to another screen or killing app or sending it background? How can user achieves unloading and reloading on memory? 4. On diagram (11:40), instead of viewModel, it should be viewController to connect S3 imho, since we locate SDWebImage on UI. Am I correct? 5. On (15:30) Photo and Album seems duplicated imho. Photo can be treated as an album with only one photo. so, we don't need any new cell class for photo. Bcs on UI, the only difference is a dot indicator. No need to duplicate them imho. 6. On 15:30, ViewModel is conforming UITableViewDataSource and UITableViewDelegate. Do you think is it a violation of Separation of Concerns? Instead, what if we define a CustomDataSource that conforms those protocols and keeps data inside and define an instance of CustomDataSource in ViewModel? 7. Also, on 15:30, since we use CollectionView, protocols must be UICollectionViewDataSource, UICollectionViewDelegateFlowLayout. 8. I see http instead of https. Is interviewer gonna take this as a negative signal for security or he would ask me if it's a typo? (I mean in real world Meta SD interview.) Thanks.

Sometime interview is actually also based on the interviewer attitude as well, this is a double side selection also. I recently interviewed with Monzo bank, and rejected by the coding stage. The guy can not say anything about valuable feedback on my worked solution. Instead ask me why u want to implement Protocol on time limit tasks? 😮 I thought this is a simple clean way to do so. And in then end I asked they interviewer, what u don’t like in Monzo, he said well, I don’t like others review my proposal it take time and waste. And for other questions he just answer mess. I start from this stage I found out this is not the company I will like also😂

Would it be better for basket to use PUT instead of PATCH so you don't need to call the api multiple times for any item changes? Also what is the advantage of using SSE over Websocket in this case?

Thanks for a great video :) but Binding [ˈbaɪn.dɪŋ] ;)))