Better Android Testing at Airbnb (Part 6)
Article Summary
Airbnb's Android tests take 2 hours to run but finish in minutes. Here's the CI infrastructure that makes it possible.
In the final part of their testing series, Airbnb's Android team reveals how they orchestrate automated tests at scale. This covers test generation, Firebase integration, and the tooling that ties their entire testing framework together.
Key Takeaways
- Kotlin scripts auto-generate JUnit tests by parsing Fragment classes with AST
- Only tests affected modules, cutting Firebase costs and test time significantly
- Flank shards 2 hours of tests into parallel runs finishing in minutes
- Custom tooling auto-posts Firebase failures and Happo diffs to PRs
- Pixel 3 devices run tests 2x faster than original Pixel hardware
Critical Insight
Airbnb built a fully automated CI pipeline that generates tests, detects changes, handles Firebase outages, and surfaces results directly in PRs without manual intervention.
