UBER System design | OLA system design | uber architecture | amazon interview question

Systems design: What is the system design of the Uber App?
Systems design: What is the architecture for the OLA?
Systems design: What is the software design of the LYFT App?

Answer to all of the above questions is here, though I have explained much about Uber's system design, but for interviews you can adopt the same answer to all of the cab aggregation services question.

Good reads:

[vaibhavbhardwaj]

Key takeaways :
1. Web sockets must be used for such application as the communication is real time and lot of to-fro communication happens between client-server for which web sockets work the best
2. the location update happens asynchronously using a queuing system like KAFKA, as this is a write heavy operation .
3. Each location would map to a grid id on a 2D matrix and the location service would use the nearby cells on grid to fetch the drivers in vicinity.
4. The APP servers are stored in a Ring (based on consistent hashing) and each APP server caters to different set of cells of the Grid. Each node knows about each other through config publishing mechanism and any call to any server would be redirected to the correct node

[vm]

Binge watching the system design videos on this channel. This is pure gold and free on youtube for everyone to watch! Thanks a lot Narendra. You clearly put in a lot of effort making these videos.

[antonyspiano]

I saw you saying sorry, Boss you are a genius and selfless person. Never say sorry again. I get reminded of mistakes and never said a sorry. Great work!! and Thanks for making me love my job .

[dextermorgan]

Few suggestions :
1. Websocket is being shown as an API Gateway which is incorrect.
2. Websocket comes with its own complications like failure on firewalls.
3. In system design, we don't focus much on the implementation logic. Good that you explained concept of cell but that's not a very important piece. Thats more of a low level implementation.
4. Support for NodeJs is partially correct. Java or C# can scale better than NodeJs in a multi threaded environment. Though Nodejs is fast to develop and deploy. But when threading comes there are better alternatives.
5. Discussions should be more focussed around DB and type of DB choices with reasons.

[mdalaminmahamud]

I really appreciate the amount of effort you have put for this system design talk. Thanks for sharing such valuable information in a short time span.

[NilanshuSharma]

Appreciate you taking stuff from real engineering blogs, instead of discussing a hypothetical design. Thanks for the effort!

[divya-djpl]

This question was asked for me 15000 per month job as a fresher🙂

[eruabid]

Great content, laid out in a concise manner, appreciate the effort you put into making these systems design video series, keep it up.
Cheers.

[UntamedRogueMavrick]

Hi Narendra, Thanks a ton. I could understand the system design better and could get the job offer from the knowledge I got from this series. Thank you not only because of the help you did by posting all the videos on system design but also for helping me by answering my queries personally on the LinkedIn. I kept on browsing the youtube to find out some quality content, but here is the home of understanding almost all types of designs questions.

[saritakhatun]

I think U are 1st who providing confidential knowledge ....openly. Thanks I appreciate U.

[jayeshbaviskar]

I have gone through many Design Explanation Video but I must say that This is the Best Uber Explanation Video I ever have seen.

[NitishSarin]

Damn, you are just so awesome. You will definitely definitely earn more and more subscribers, just like how Gaurav Sen did. You guys are what every developer on youtube needs. Thanks for the initiative! :)

[dhyanimation]

This is gold, I'm looking forward to how tech enables ground ops for mainstream products.

[vivekchoudhary]

this is gold, and the efforts and your persistence is beyond praiseworthy <3

[aravindswarana]

I spent 11000 for educative.io for System design but watching your vidoes. Thanks a ton for your help to community.

[himanshugupta]

Just amazing, I never saw this kind of clear explanation about the system design. Keep it up

[swapnilpatil]

Awesome video !
Please help me with below two questions.
1. Driver location is updated to nodes in hashring depending on s2 cell. Since car is in motion location and s2 cell will keep on changing. Suppose location is store on server s-1 which handles cell c-1 and now driver has entered cell 2 and location is updated to c-2 which is store on server s-2. How would server s-1 know that driver has moved out of cell c-1 to remove driver from it ?
2. Is driver location stored on cache for each server or there is cache cluster which stores location information.

[krishnan]

Hey man ! Very useful and nicely presented. I've started loving all your videos and have literally binge watched 'em all. In this video, I was also expecting you to cover up how Uber matches the pool rides .. basically a map route matching algorithm.. if you could brief on that, it would be very useful ! Thank you and wishing you huge success ahead !

[Theeugeneedward]

Narendra, hats off to you! Your architecture presentations are world class. Your presentation and organization of material is excellent. Thanks very much for your great service!

[jkuhede]

Saw this video in 2018 and it looked so tough, coming back here with some knowledge it makes it look somewhat understandable like 60% I can grasp just by watching this video so please you younger lads and ladies don't get disheartened if you don't get it on the first try .