Thank you for the insightful video on design systems. I appreciate the clarity in your explanation. I'm curious about the "pricing calculation " process after selecting a driver. In the typical scenario, a rider selects the origin and destination first and then would like to see the corresponding fare before confirming the trip request. It seems intuitive to have the pricing information available at this stage, and then proceed to assign a driver once the rider confirms the trip. I understand this may involve simplification, but it seems crucial to treat pricing as an independent factor from the driver assignment. However, I acknowledge my perspective might be influenced by the absence of Uber in Iran, where the services we utilize may follow a different implementation approach. If my understanding is incorrect, I would appreciate any clarification on this matter. Thank you again for the informative content.
Its better if you provide the explanation of the requirements first, before solving the problem. But the way you are explaining is great, thanks for such great content.
Thanks for the wonderful explanation, please keep on posting more videos and playlist related to LLD , design patterns, HLD with proper roadmap from scratch to end in order.
Thanks for taking the time and doing this video. It is very interesting and informative. But can you please slow down a little bit when you are talking. Thanks
There are many LLD questions on the basic features of large systems like WhatsApp(How to manage users, send messages, receive messages, and manage groups), Facebook, and Twitter. Please help us by making videos on that too by covering the basics of those. It will be really beneficial for us.
Thanks, Keerti for creating this excellent video with the entire thinking flow with a coding sample. Really appreciate your time and effort behind such a great video. Expecting more from your channel.
I really appreciate ur work and effort u put to make video sis , I think ur channel stands out unique compared to others where others r teaching abt only a particular language, ur focusing on smtg which is more imp and unnoticed,where many youtubers won't cover , thanking you 🎉❤for ur efforts ur putting to make quality content for us , love frm Bangalore
Very nice content created. Kindly prepare videos like this in detail since I had seen your mock interview videos earlier they were not much in depth and in real interviews , interviewers ask in detail
Trip Manager should have a composition relationship with RiderManager, but an aggregation with Driver Manager, because a trip is created only if a rider is there. It's like a body can be there only if eye is there. Rider is totally a part of the trip, particularly when rider is creating trip. Although I think this should be true for the limited functionality that we discussed right now. Maybe for more expansion its better to have an aggregation relationship with rider manager as well
Hi Keerti, Thanks for the video. It was super clear. I just had one doubt. Why do we need an instance of riderManager and driverManager in TripManager. I see those instances are not being used anywhere in the TripManager class.
Excellent contribution. Please keep it up कभी महक की तरह हम गुलों से उड़ते हैं कभी धुएं की तरह पर्वतों से उड़ते हैं यह क्या उड़ने से ख़ाक रोकेंगे कि हम परों से नहीं हौसलों से उड़ते हैं
i think trip manager has strategy manager to decide price and driver mantching strategy , is it missed in class diagram of tripmanager to add private instance of strategy manager ?
Thanks keerthi for an excellent video. It was very helpful as we used to see many video with explanations but not this much detailed explanation with code and UML. Please add more designs like this with code and UML. Hats off to you for your contribution
Superb video, can see the work gone behind it. One tweak could be having a TripRequest class that has status: {pending, accepted, in progress, completed, cancelled} etc and when the driver accepts, it creates a Trip object and returns it.
Hi Keerti, when it is a coding problem, I will try to find solution to it whereas for system design i dont know what i am doing and also, it's not right if I just do as you do by mugging up.. Please help in understanding how can I gain confidence in system design things
Thanks Keerti for yet another amazing video. I have a noob question: The RiderManager was created with a single instance. I suppose that is a single instance for each host (assuming we will have the code deployed in multiple hosts). How do we manage those multiple single instances from each host working on a single or multiple DB? Thanks in advance.
Thanks for putting a lot of effort in making UML diagrams as well as clearly explaining thought process behind chosing class relationships & Also, for explaining how to make design scalable and extensible in case if we need to add different strategies for driver matching and price calculation. BTW, this is my first youtube comment ever. Thanks Again!!!!
Great explanation, I just assumed that we send requests to nearest drivers and pricing is all based on km travelled. so I didn't get into this pricing strategy and driver strategy, but its a good thing to demonstrate in an interview.
@keerti You mentioned all the managers should be singleton across all trips, I believe all the manager should be singleton for a particular trip instead of all trips. please correct me if I am missing something here.
If trips cannot exist without TripManager and you are making that a composition, then why can't we say the same thing about RiderManager? Riders cannot exist without RiderManager as well. I am unable to clearly understand what's the difference between the relationships of Trip-TripManager versus Rider-RiderManager.
So there can be a case where the Riders can exist without the rider manager totally based on the requirement of the system needed, that's why she used aggregation relationship here Otherwise if there is a requirement that the rider and driver *CANT BE CREATED* without a Rider or driver manager then these should be the composition relationship Timestamp: 7:20
Mind blowing explanation, best content ever found on LLD so far, really liked the flow of your explanation....overview, UML class diagram and then code. Thanks Keerti!! ✨
Nicely done. Thanks. Very much informative and brainstorming. We can decide to do Strategy run time, may be based on timing or location. That would be nice.
are the maps inside all the above singleton classes thread safe? if not, we might have to have mutex lock before setting the value inside map& then unlock right ?
Attendance marked . This content is better than paid courses that white board is worth ❤️. Going replay to the same comment when i complete the whole video ❤️
where do we use these classes and create this structure while building the product? FE? BE? or this is just some theory stuff that is never used in actual implementation?
@23:30 Hey Keerti, There is relationship between TripManager to StrategyManager so don;t u think the relationship between StrategyManager and TripMetadata is redundant?
An excellent LLD video; I appreciate the work Small Doubt: why are we passing pricingStartegy and driverMatchingStartergy pointers to the Trip class? In what scenarios these instances of strategies are needed in Trip class.
She is assuming that the pricing strategy and driver matching strategy will vary with different trips. This is a little albeit to the real Uber implementation where these strategies are independent and vary based on the geolocation and timing of the trip request. Its a design problem, theres no ONE right answer.
Thank you so much, Keerti. What an amazing video. Your thoughts and efforts are absolutely visible. It cleared so many of my concepts and doubts, at the same time, helped me a lot with my confidence for the interviews and LLD rounds. Subscribed and definitely gonna share this video and your content with others. Big thumbs up.
Nice explanation and use of those design patterns ! One question, why do we have a strategy for matching of drivers to riders? In actual scenario, it is upto the drivers in that region to accept the user's trip or not right? The ride request of the user is sent to all the drivers in that bounded region where the user has to start the trip I believe. To emulate in this LLD, we can maybe use a mediator for communication of a ride request to all drivers nearby, and whichever driver accepts the trip request, we again use the mediator to inform the owner of the ride request, i.e, the rider. How does that seem? Waiting for your feedback !
i am very confused choosing abstract class and interface for achieving abstarction By choosing anyone implement in Uber/Ola Low Level System Design it does not effect any thing and we make the code loose coupling with one to other . In my case i choosing according to derived class 1.if derived class extends only multiple classes then i choose interface because java does not support multiple inheritence. can anyone tell me which one should i select and in which case?
Thanks~~ understood patterns for the first time. Used to read it always but never found good examples to solidly my understanding.
All the effort you put in to explain all these concepts is just beyond amazing and makes learning so much easier!
Thank you for the insightful video on design systems. I appreciate the clarity in your explanation. I'm curious about the "pricing calculation
" process after selecting a driver. In the typical scenario, a rider selects the origin and destination first and then would like to see the corresponding fare before confirming the trip request. It seems intuitive to have the pricing information available at this stage, and then proceed to assign a driver once the rider confirms the trip. I understand this may involve simplification, but it seems crucial to treat pricing as an independent factor from the driver assignment.
However, I acknowledge my perspective might be influenced by the absence of Uber in Iran, where the services we utilize may follow a different implementation approach. If my understanding is incorrect, I would appreciate any clarification on this matter. Thank you again for the informative content.
It's gives me atmost satisfaction as I understood this video very well❤❤❤
Its better if you provide the explanation of the requirements first, before solving the problem.
But the way you are explaining is great, thanks for such great content.
One of the best LLD videos I have watched so far! Thank you.
Excellent video. This is like first video I have seen on design and you made it look so easy. I know the effort behind, really appreciate it !!
Thank you so much keerthi. I had several doubts in lld, this video cleared almost all of them.
Best Low Level Design Tutorial Thanks for clear-cut explanation.
Amazing keerti... understood the lld first time... but a request... explain it slowly...its very fast
Thanks for the wonderful explanation, please keep on posting more videos and playlist related to LLD , design patterns, HLD with proper roadmap from scratch to end in order.
Hi Kreeti great work , I have watched all LLD videos they are very well explained , I really appreciate yr time and effort.
My quest for the best LLD tutorial concludes here
Thankyou for such amazing explanation .Apreaciate the hardwork you have put
Thank you, no one explained LLD the way you did.
thank for creating these excellent LLD,with such effort
Super helpful. Thank you for putting in all the effort to create this.
Thanks for taking the time and doing this video. It is very interesting and informative.
But can you please slow down a little bit when you are talking.
Thanks
this video is very good, lot of videos only describe but will not show in coding.
There are many LLD questions on the basic features of large systems like WhatsApp(How to manage users, send messages, receive messages, and manage groups), Facebook, and Twitter.
Please help us by making videos on that too by covering the basics of those.
It will be really beneficial for us.
Thanks, Keerti for creating this excellent video with the entire thinking flow with a coding sample. Really appreciate your time and effort behind such a great video. Expecting more from your channel.
Thank you so much Keerthi It's a really nice explanation.
thanks keerti !! this very interesting and important topic .
really help to understand the concept and LLD design flow...🤩
please also show us on how you are building the code in the end. That would be helpful
Very understandable video. Super helpful.
Greatttttt please dont stop this series
Excellent work. Kudos and thanks.
I love your attitude. Thanks for the video!
I really appreciate ur work and effort u put to make video sis , I think ur channel stands out unique compared to others where others r teaching abt only a particular language, ur focusing on smtg which is more imp and unnoticed,where many youtubers won't cover , thanking you 🎉❤for ur efforts ur putting to make quality content for us , love frm Bangalore
This is excellent! Thank you for creating this video.
Thank you so much Keerti for putting so so much efforts in the videos. ❤. Keep growing and Glowing !
Very nice content created. Kindly prepare videos like this in detail since I had seen your mock interview videos earlier they were not much in depth and in real interviews , interviewers ask in detail
I don't think Strategy Manager has to be singleton! But overall great explanation :)
Such an informative video, Thanks Keerti !!
Amazing video. Described very well.
This is so helpful. Thanks for the video Keerti
Great Work please make a video on low level design of CRED app
This is so helpful mam, Thanks a lot for the efforts:)
Trip Manager should have a composition relationship with RiderManager, but an aggregation with Driver Manager, because a trip is created only if a rider is there. It's like a body can be there only if eye is there. Rider is totally a part of the trip, particularly when rider is creating trip. Although I think this should be true for the limited functionality that we discussed right now. Maybe for more expansion its better to have an aggregation relationship with rider manager as well
Its a design problem, theres no ONE right answer.
This is really amazing.. thank you Keerthi..
dedication what it is!! Hats off to u di
I really appreciate the amount of work you have put into it so I shared in my group
Hey could you please provide the code in java
Please 🥺
What a coincidence .... i need in java too😢
Amazing Explannation
loved this
Thank you dear for your efforts god bless you ❤❤
Thanks nice content. Do we have separate video for strategy design pattern?
Hi Keerti,
Thanks for the video. It was super clear.
I just had one doubt. Why do we need an instance of riderManager and driverManager in TripManager. I see those instances are not being used anywhere in the TripManager class.
Super highly appreciated the efforts.
Wow ! Keerti- great work
Excellent contribution. Please keep it up
कभी महक की तरह हम गुलों से उड़ते हैं
कभी धुएं की तरह पर्वतों से उड़ते हैं
यह क्या उड़ने से ख़ाक रोकेंगे
कि हम परों से नहीं हौसलों से उड़ते हैं
Finally, was waiting for this!
Hope you like it! ❤️😇
Improv: Builder patterns can used for the Metadata or other Objects instead of Constructor parameters.
Thank you for this amazing video. Which IDE are you using for building and running this project ?
Visual Studio
Amazing content, Keerti. So helpful.
Very nicely explained and implemented Keerti! Thanks for sharing!
Loved the content and the way you explained. Please continue creating more such content. ❤
i think trip manager has strategy manager to decide price and driver mantching strategy , is it missed in class diagram of tripmanager to add private instance of strategy manager ?
Thanks keerthi for an excellent video. It was very helpful as we used to see many video with explanations but not this much detailed explanation with code and UML. Please add more designs like this with code and UML. Hats off to you for your contribution
Superb video, can see the work gone behind it.
One tweak could be having a TripRequest class that has status: {pending, accepted, in progress, completed, cancelled} etc and when the driver accepts, it creates a Trip object and returns it.
Thanks for the detailed explanation
Excellent video Keerti..
Hi Keerti, when it is a coding problem, I will try to find solution to it whereas for system design i dont know what i am doing and also, it's not right if I just do as you do by mugging up.. Please help in understanding how can I gain confidence in system design things
Thanks Keerti for yet another amazing video.
I have a noob question:
The RiderManager was created with a single instance. I suppose that is a single instance for each host (assuming we will have the code deployed in multiple hosts). How do we manage those multiple single instances from each host working on a single or multiple DB? Thanks in advance.
This is so so helpful. Thanks Keerti for making this kind of video. Now you have responsibilty of making such more videos.
Thanks for putting a lot of effort in making UML diagrams as well as clearly explaining thought process behind chosing class relationships & Also, for explaining how to make design scalable and extensible in case if we need to add different strategies for driver matching and price calculation.
BTW, this is my first youtube comment ever. Thanks Again!!!!
Loved the video and the word Hotch Motch😊
Great content. Very helpful.
Great explanation, I just assumed that we send requests to nearest drivers and pricing is all based on km travelled. so I didn't get into this pricing strategy and driver strategy, but its a good thing to demonstrate in an interview.
We have different cars,auto avaible over uber and ola both, that we need to mention in this , right ?
Thankyou for the effort! 🙏🏼😀
What a nice explanation.
@keerti You mentioned all the managers should be singleton across all trips, I believe all the manager should be singleton for a particular trip instead of all trips. please correct me if I am missing something here.
@KeertiPurswani Thanks so much♥ Is the manager class same as service class we use in Spring Boot?
If trips cannot exist without TripManager and you are making that a composition, then why can't we say the same thing about RiderManager? Riders cannot exist without RiderManager as well. I am unable to clearly understand what's the difference between the relationships of Trip-TripManager versus Rider-RiderManager.
So there can be a case where the Riders can exist without the rider manager totally based on the requirement of the system needed, that's why she used aggregation relationship here
Otherwise if there is a requirement that the rider and driver *CANT BE CREATED* without a Rider or driver manager then these should be the composition relationship
Timestamp: 7:20
I love the intelligent lady ❤
Thanks for the session, its amazing !But quad ka explanation kidhar h ...
Channel kholke dekha toh karo 🫢
Here’s the link. Hope you like it ❤️
ruclips.net/video/kClPBNmTCf0/видео.html
Why are we maintaining hashmap of riders & drivers objects at code level? When the driver assignment happens wont this be at DB level?
Mind blowing explanation, best content ever found on LLD so far, really liked the flow of your explanation....overview, UML class diagram and then code. Thanks Keerti!! ✨
Nicely done. Thanks. Very much informative and brainstorming.
We can decide to do Strategy run time, may be based on timing or location. That would be nice.
are the maps inside all the above singleton classes thread safe? if not,
we might have to have mutex lock before setting the value inside map& then unlock right
?
I think you did not use riderMgr and driverMgr in your tripMgr at all, can we skip it in UML too?
Attendance marked . This content is better than paid courses that white board is worth ❤️. Going replay to the same comment when i complete the whole video ❤️
Thanks for the video. It's very informative and good. One request though. Can you please create a playlist for all the design patterns?
Nice video. Would it be possible to have the code for the same in Java?
Great work!!
Nice explanation
where do we use these classes and create this structure while building the product? FE? BE? or this is just some theory stuff that is never used in actual implementation?
wow, amazing.
Why is trip manager creating rides or accepting rides? Shouldn't riderMgr be requesting rides, and the driverMgr be accepting rides?
@23:30 Hey Keerti,
There is relationship between TripManager to StrategyManager so don;t u think the relationship between StrategyManager and TripMetadata is redundant?
An excellent LLD video; I appreciate the work
Small Doubt: why are we passing pricingStartegy and driverMatchingStartergy pointers to the Trip class?
In what scenarios these instances of strategies are needed in Trip class.
She is assuming that the pricing strategy and driver matching strategy will vary with different trips. This is a little albeit to the real Uber implementation where these strategies are independent and vary based on the geolocation and timing of the trip request.
Its a design problem, theres no ONE right answer.
Thank you so much for this video
Thank you so much, Keerti. What an amazing video. Your thoughts and efforts are absolutely visible. It cleared so many of my concepts and doubts, at the same time, helped me a lot with my confidence for the interviews and LLD rounds. Subscribed and definitely gonna share this video and your content with others. Big thumbs up.
Keerti Rocks
Please make some more on lld 😊
Nice explanation and use of those design patterns !
One question, why do we have a strategy for matching of drivers to riders? In actual scenario, it is upto the drivers in that region to accept the user's trip or not right? The ride request of the user is sent to all the drivers in that bounded region where the user has to start the trip I believe.
To emulate in this LLD, we can maybe use a mediator for communication of a ride request to all drivers nearby, and whichever driver accepts the trip request, we again use the mediator to inform the owner of the ride request, i.e, the rider. How does that seem?
Waiting for your feedback !
I am not able to understand : Why you have created riderMgr and driverMgr in TripMgr?
They are never initialized or used!
Thanks, nice content❤
amazing video!
i am very confused choosing abstract class and interface for achieving abstarction By choosing anyone implement in Uber/Ola Low Level System Design it does not effect any thing and we make the code loose coupling with one to other .
In my case i choosing according to derived class
1.if derived class extends only multiple classes then i choose interface because java does not support multiple inheritence.
can anyone tell me which one should i select and in which case?
Do you think somebody can come up with this solution and then code it in a hour or hour and a half long interview?
There's issue in Audio Quality :)