Basic System Design for Uber or Lyft | System Design Interview Prep 

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I'm not a software engineer or developer, but you just had my eyes glued to the screen for 16 minutes. While I might not understand the concepts in this system design, the way the information was presented was extremely well done and approachable for a wide range of viewers.

Great content. Please make more videos. Content is king. Even though there are tons of videos on Internet about System Design but the kind of clarity that one gets from these videos is unparalleled. It's to the point. Worth watching again and again.

These system design videos are awesome! Really interesting topic with good visual explaining, keep up!

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This is so good. I have searched for this type if videos but this is very very good. Clean fast forward explanation with much detail. Thank you!

I cannot believe you've placed many valuable topics in a 16-minute video! This was worth more than a 12-hour course! Thank you!

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One of the best systems design videos I've seen! Great job!

WxCtly what I needed. I don’t have time to learn syntax, so I generate all my snippets but I need form of macro assembly training to manage larger models thanks a million

The way he explains everything is just pure gold

You're very good at explaining! Thanks for this

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pretty decent take - I've seen some comments on specific improvements, but narrowing the scope of a given problem on SD interviews is A MUST, otherwise you won't make it inside the given time frame. functional/business prioritization on this case was very well done!

I've seen lots of system design prep videos on youtube especially cause I'm being interviewed right now for Senior BE position and this guy really shows valid ideas on required abstract level. For everyone who has doubts, "yes" this is proper level for senior position and his conceptions are valid for every-day usage with this level of abstraction.

This is one of the most educative videos I have seen in a long time

This is absolutely perfect! Thank you so much for sharing!

This guy is really good at teaching, very informative and concise, thanks.

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I wish I can lecture the interviewer like this. Very well articulated.

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Good analytical skills man. Congrats!

thank u for making these videos. love to see how u would implement these in code

instant subscribe over here. very clear information, amazing content. Keep it up! Thanks

These videos are so good Hope you post more

Haven't started watching the video yet but I know I have to subscribe!

This is a really good explanation. Thank you for sharing your knowledge.

I did not know that spark could be used to solve problems in this kind of project, very informative and detailed explanation thank you.

Beware that the second you mention a pub/sub system in an interview you may have to touch on the topic of message ordering. The immediate scalability of kafka event streams seems great in paper but if you have to process things like chats in order you may have to make kafka store all the relevant events in one partition which isn't scalable.

This is super cool man, thanks so much. Just a small feedback, I clicked on the video because I saw a really nice diagram. I'm a highly visual person, probably like a million others and when I saw your drawings I was a bit dissapointed, not because they are bad but because studying with other people hand writting definetly slows you down like "what does it say here?" Don't take this the wrong way, you are a genius, keep up the good work.

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Mind blown... this was amazing to watch...

These types of videos imo are the best as these can get one out of “tutorial hell”. Although challenging - I think it forces me out of my comfort zone and actually makes me think on how to program and shows me gaps in my knowledge. New subscriber - I would like to see more of your videos!

I was asked to design Über in an interview about a month ago, if only I came across this before

Excellent architecture work there bud.

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Insane! Thank you

Got me subscribed! Nice.

This is a fantastic video - lots of content in a short space of time delivered clearly - thanks! One question I had was regarding storing of driver locations and loading them into H3 - how would that be accomplished using the DB design here? Or would the H3 index constantly be updated separately? Thanks.

Thank you, it was interesting and informatively

Visual explaination was comprehensive

tbh I am very impressed about a content, that autor produced despite of his young age he has a lot of knowledge in projects and it's greate! I found a lot of interesting things. Thanks a lot!

I feel like you can make a whole series on this one problem man, would love to see an extended version of this where you go a little slower and into more detail. Either way, this video is super useful!

Great content here. Subscribed

Love this!

I've heard Uber uses a structure called a Quadtree to split their map area into grids for easier rider - driver matching.

Amazing content. Instant sub.

one organization improvement I'd make on the diagram, not only for readability, but also for a better notion of resources management, would be delimiting some domain/namespace boundaries, organizing the services appropriately: - Client APIs - External APIs / Services - Events Bus - Internal APIs / Services - Data / Storage etc

thanks for the information.

Fantastic video.

You got 1 more subscriber. Please keep posting with such a great explanation

This is awesome! Could you kindly do a video on how to work around the same, like making this a complete project maybe. Thank you

Few things that felt like hand waving: 1. How is the driver location updated in the data structure? Uber has a few million drivers (say 3M) and if they send location every 3 seconds, there's 1M updates coming in every second on an average. 2. It seems disparate events are put on Kafka (ride request, payment, driver location), so instead of showing one Kafka box, perhaps having more than one would've helped. Currently the diagram looks like a spider web, and that's mostly because all the services on the right subscribe to one Kafka box. 3. It's not clear how the global indices are implemented in the trip DB? Is the data duplicated? 4. What's in Redis that is used for pricing calculation? 5. Can we hope that good content will be supported by a diagram not drawn by a 3-year old? Why, there are probably a dozen tools that can be used to draw boxes and stuff. An actual system design interview is close to 45 minutes, so, three times the duration of this video. All systems consist of load balancers, event bus (Kafka), distributed cache (Redis), so, any candidate can draw those boxes. The details are what make for a more real interview experience.

Cool stuff! Anyways, I think it is very important to get the requirements as clear as possible before jumping into the design. Ask questions, make sure you are not assuming too much. This solution could be way over-engineered for some cases and it might rise some red-flags among the interviewers.

Thank you. This is amazing

This video is amazing and was recommended at just the right time for me. Subscribed within 2 minutes of watching!

lisan al gaib, he is the chosen one

Excellent vid! Thanks! Question: What is that drawing tool being used..?

im so blown away

Amazing except I needed this 5-6 years ago 😂

Love this video

Hey, first of all great video, great content, exceptional delivery - seriously wow. Around minute 6:20 of the video you correctly say that the DB will have to be able to scale horizontally as it is expected to be very large with high traffic coming in. You said, the easiest way to do it is by sharding, which left me wondering, did you consider a noSQL option? Clearly it is easier for horizontal scaling. If so, why did you decide to stay with the relational approach?

I think this is kind of a intern/junior level software design, which is good, but certainly lacking in most details that these systems require. For example, when you talk about sharding the database, it's not so easy to say just shard it. Some of the problems with sharding a db using such a key in this way would be referencing and constraint enforcement as well as update request stream consumers and their ordering. Also, your "rider and driver APIs" discussion is...flawed. Most of the system design for those APIs should be about actual data modeling and api design. You also can't just say to use "websockets" because it has some very bad tradeoff. For example, sockets are not stateless and requires consistent connection, which you will definitely not have in a driver's mobile phone. Another problem is data consistency. If your data producer sends a message to the socket but the receiver was in a temporary disconnected state; what happens to that request? Also, since it's websockets, who is doing the broadcast? And since cars can "come online" at any point; does the requester keep resending the request? If so, then isn't polling necessary anyways? If the concern is concurrent request scale, it's much easier to shard the api using the same H3 algorithm, isn't it? There are a lot more problems with this design, but for a student and assuming an ideal world, this is a good first draft. I would say though that it would be much better to assume those ideal conditions (perfect and constant connectivity, some scale target, some location target, etc), and then to better simplify your solution. I feel like a big problem with this presentation is the use of buzzwords without knowing how they work or what they mean. I'd rather you use fewer techy sounding words and be more accurate with your solution because your interviewer will certainly see right through these buzzwords and you will get drowned with real world problems that you can't explain (like the Kafka network limitations that makes this just not possible as described) Also, for this channel in general: this is not a good interview question for system design. Usually, system design interviews are more for mid level engineers so doing it at this scope is not good enough. When I interview engineers for system design, it's okay to start with a broad system question, but it's much more revealing to dive into one specific area because the complexity of a problem is when you have to design in the details. I think even just the payment processing is sufficiently complex to deep dive let alone trying to design every system in Uber. edit: I'm a senior software engineer at a FAANG and have conducted 100+ mid level engineer interviews.

Awesome!

It is very important to me levels to development the system like uder

It was just amazing, I really wish there was some course.

This is Gold

This is amazing! As im in a junior developer, this video is inspiring me with verious concepts of the highly efficient architecture in real time situation and suggesting ultimate goal! Thanks for sharing this great insight!

Great video

great video. What software did you use to make the diagrams and presentation?

like it these architecture use case solutions

excellent

We call these Activity Diagram in UML/SysML

Good stuff :)

Thanks for the video, it's very educative. I didn't fully get how global indexes are working. Would appreciate it if you can elaborate on it.

You inspire me mehn

It looks like a rouiting component is missing. Pricing clearly depends on the route length (the mentioned surge just scales this price up) and, sometimes, on traffic jams. You can't calculate ETA without a route. And most client UIs draw the route on the map.

The main challenge of Uber or Lyft , is the massive number of updates that they have to do in realtime and also persist , i don't see this tackled here ? for this Uber using a variance of quadtree

You know ball dude, keep it up

Hey @interviewpen, great video, thanks! One question I have is why did you go for the server side API app with load balancing rather than an API gateway to access Rides (and maybe other services) directly? I know load balancers and gateways are not mutually exclusive, just interested why you went with one app routing all the client requests? Another question is about payments, will the user get payment confirmation on the client side as well? You show in the little diagram that user will receive the confirmation after the webhoot will send the message to kafka, so the server side of the app will be subsribed to the topic of payments filtering by user_id (for example), but how would the client side receive the confirmation afterwards?

great video

great video, why a monolithic db? should the microservices not own their own data?

good information. im subscibe you.

During the review at 14:00 the presenter makes a mistake and starts talking about the ‘driver’ looking for rides and viewing rates. He even red highlighted the driver box on accident. I think he meant to start with ‘rider’

One critical part that is missing in this SD interview is, discussion about different trade offs. e.g. in the matching service, why use Uber's H3, what about quadtree, geohash and Google's S2, what's the pros and cons of using these different methods.

I’ve watched quite a few of your videos and I see that you mentioned websocket, but you don’t elaborate about the impact of that in terms of how to scale it. Thank you 🙏

This is great, now how do I explain requirements to someone who has no idea about uber/lyft or applications in general? You have good intuition here used to synthesize requirements and identify possible issues immediately. That intuition comes from knowing what you're trying to build, for new product development where the final product is not clear, how could we handle that?

Would you go for SQL or NoSQL based DB here? Great video btw!

Mantap bang makasih

Please upload more video of system design

Really great video! How is the calculated price communicated from the Pricing service to Stripe?

FYI (for those interested in project and program management) systems design and project management works hand-in-hand. Technical Project Management is breaking these down one by one, little by little then coming up with a solution - that's technical project management. More often than not, technical project managers help the engineers by solving what they cant: meaning issue X is more of a devops issue than an engineering issue, the tpm looks at the problem from an engineering standpoint, asks the devops team how to solve it, creates a plan, budget etc. If you're into firefighting all day, get into TPM, we need lots of people that wants to fight chaos.

Thank God I found u

very good

🎯 Key Takeaways for quick navigation: 00:00 🚗 Key requirements for ride-sharing: map point selection, ETA, payment, matching, real-time updates. 02:03 📡 Using an event bus (e.g., Kafka) for system communication. 04:21 📊 Structuring the database with sharding for scalability. 06:00 🌐 Efficiently indexing drivers using H3 hexagonal cells. 09:44 💰 Leveraging services like Stripe, Mapbox, or Google Maps for payments and mapping. 10:12 🚀 Implementing a Spark streaming pipeline for demand-based pricing. 13:25 🚖 Matching riders with drivers through proximity-based services. 15:43 🛠️ Opportunities for optimization, data analytics, and advanced ETA algorithms. Made with HARPA AI

What’s the pros and cons of costs, availability, and maintenance of the websocket over polling design decision?