Decomposing network calls on the Lyft mobile apps
Article Summary
Lyft's mobile apps used to poll a single endpoint every 5 seconds for everything. That "Universal Object" became their biggest reliability nightmare.
Don Yu and the Lyft engineering team share how they decomposed one monolithic API into 40+ microservice endpoints. This year-long migration involved 13+ engineers and fundamentally changed how their mobile apps fetch data.
Key Takeaways
- Single endpoint failure could break the entire app experience for users
- New architecture reduced p50 latency from 200ms to under 120ms
- Driver match notifications now arrive 20% faster after decomposition
- Team ran 28+ A/B experiments to safely migrate without breaking flows
- Shadowed 1% of production traffic to catch payload mismatches early
Critical Insight
Lyft eliminated their single point of failure by splitting one universal endpoint into isolated APIs, cutting latency by 40% and improving driver notification speed by over 20%.
