Lyft Senior Software Engineer Interview Questions

1.Walk me through a time you either broke apart a monolith into services or consolidated multiple services for simplicity. What drove that decision?

2.Tell me about a time you had to take ownership of a struggling service or system that wasn't originally yours. How did you approach it?

3.Walk me through the last major production incident you owned from start to resolution. What broke, how did you debug it, and what changes did you make afterward?

4.Tell me about a time you reviewed another team's design doc and caught a significant issue. What was the problem and how did you communicate your concerns?

5.Tell me about a time you built something that involved location data or real-time matching. What were the technical challenges and how did you solve them?

6.Describe a system you designed where preventing fraud or ensuring safety was a core requirement. How did you build those protections in from the beginning?

7.You're building a new endpoint that needs to match riders to the closest available bikes within a 200-meter radius in real-time. Walk me through your approach for the data structures and algorithm you'd use.

8.Our driver app is experiencing intermittent WebSocket disconnections that last 10-30 seconds before reconnecting. Drivers are missing ride requests during these gaps. How would you debug this?

9.We need to implement surge pricing that adjusts every 30 seconds based on supply and demand in each geographic zone. Design the system architecture for this, considering we operate in 600+ cities.

10.You're tasked with migrating our monolithic ride request service to microservices. The service handles matching, pricing, ETA calculation, and payment processing. How would you approach breaking this apart?

11.Write a function that finds all drivers within a given radius of a pickup location and returns them sorted by estimated pickup time. Assume you have a driver location service and an ETA prediction service available.

12.Design a system that can detect when a driver might be involved in an accident based on phone sensor data and automatically alert emergency services. Consider both false positive prevention and response time requirements.

13.We want to build a feature that automatically suggests optimal driver break locations based on bathroom availability, food options, and high-demand pickup zones. Design this recommendation system for our Driver Platform.

14.We need to build a cross-platform notification service that can send ride updates to riders via push notifications, SMS, and email, handling 5 million notifications per minute during peak hours. How would you design this system?

15.Design a real-time ETA service that needs to provide pickup time estimates to 500,000 concurrent riders across North America. How would you handle the constant location updates from 200,000 active drivers?

16.Design a bike and scooter rebalancing system that can predict demand patterns and automatically dispatch our operations team to move vehicles between stations across a city like San Francisco. Consider both Citi Bike dock-based and dockless scooter fleets.

17.Design the backend architecture for Lyft Business where enterprise clients can book rides on behalf of their employees, with real-time expense tracking and approval workflows. Consider that we have Fortune 500 companies booking 10,000+ rides per month.

18.Our autonomous vehicle partners need a service that can seamlessly hand off rides between human drivers and AV fleets based on route optimization and safety constraints. How would you design this hybrid dispatch system?

19.Tell me about a time you had to convince a skeptical engineer from another team to adopt your technical approach or decision. How did you handle their pushback?

20.Describe a situation where you had to mentor or help a junior engineer who was struggling with code quality or technical decisions. What was your approach?

21.Tell me about a time you had to drive a major technical decision across multiple teams when those teams had conflicting priorities or timelines.

22.Walk me through a time when you disagreed with your manager or senior leadership on a technical direction, and you had to decide whether to escalate that disagreement.

23.Describe a time you had to lead your team through a significant production incident or reliability crisis that affected riders or drivers. How did you manage both the technical response and team dynamics?

24.Tell me about a time you had to advocate for a significant technical investment or architecture change that other teams initially saw as unnecessary. How did you build support for it?

25.Estimate how many driver signups Lyft would need per week to expand into a new mid-size city like Austin. Walk me through your assumptions and how you'd validate them.

26.Our bike availability dropped 15% in San Francisco last month, but ridership demand stayed flat. No new competitors launched and weather was normal. How would you investigate this?

27.If we reduced driver wait time at airports by 30% through better staging algorithms, estimate the annual revenue impact for Lyft. What assumptions would you make?

28.Lyft Business accounts for 20% of our enterprise client's employee rides, but we want to capture 60%. Their employees currently use taxis and competitor rideshare. How would you size the opportunity and build a growth strategy?

29.Design an experiment to test whether showing drivers their potential hourly earnings before accepting rides increases acceptance rates. What metrics would you track and how would you handle confounding factors?

30.Estimate the cost impact if we guaranteed 3-minute pickup times for all Lyft rides during peak hours in downtown San Francisco. Walk through your assumptions about driver density, positioning, and operational changes needed.