Lyft fares that track real-time supply and demand: design the system
Company: Lyft
Role: Product Manager
Category: Product Design & Strategy
Difficulty: medium
Interview Round: Other
Design dynamic pricing for Lyft rides: fares that change with real-time conditions instead of staying fixed. Explain what the pricing is meant to achieve, how prices are calculated and updated, what riders and drivers see, which limits apply, and how you would know the design works.
```hint Start from what breaks
Picture a sudden spike in ride requests while fares stay fixed, and work out what happens to riders, drivers and wait times. That tells you the job pricing has to do.
```
### Clarifying Questions
- Does the design cover only what riders pay, or driver earnings too?
- Which products are in scope: standard rides only, or also shared rides, bikes and scooters?
- Is this a first version, or a redesign of pricing that already varies with demand?
- Should I focus on the pricing logic, the rider and driver experience, or both?
### What a Strong Answer Covers
- The marketplace goal pricing serves, and how it is balanced against rider trust and driver earnings
- How prices are computed and updated: inputs, granularity in space and time, and how changes are smoothed or bounded
- What riders and drivers see, and the options riders have when prices are high
- Safeguards for fairness, emergencies and attempts to game the system
- A success metric with guardrails, and an experiment design that accounts for marketplace interference
### Follow-up Questions
- Drivers in one area start logging off together to push prices up. How would you detect and respond to it?
- Should a rider's price ever depend on anything about that rider, such as how often they ride? Why or why not?
- How would you handle a stadium crowd all requesting rides at the end of a game?
Overview: A product design question asking how Lyft should set ride fares that change with real-time supply and demand. It tests marketplace reasoning, how prices are computed, smoothed and capped, what riders and drivers see, fairness safeguards, and how to run experiments in a two-sided market.