Airbnb·Software Engineer·Technical Phone Screen
- You're handed a Python module that reads geospatial data (CSV and GeoJSON), computes distances between points, clusters nearby locations, and writes summaries. Walk through a code review: what correctness bugs, numerical issues, and edge cases would you flag?
- What performance improvements would you propose for this geospatial pipeline, specifically around vectorization, spatial indexing, and I/O batching?
- How would you refactor this module to improve maintainability? Think about modularization, type hints, and documentation.
- What security considerations apply to a module like this, particularly around input validation and dependency management?
- Outline a testing strategy for this module, including unit and integration tests. What fixture data would you use?
- Estimate the time and space complexity of the critical paths in this pipeline, particularly distance computation and clustering.
- Which Python libraries would you choose for this geospatial pipeline (e.g. pandas, shapely, pyproj) and what are the trade-offs between them?
“The CRS mismatch thing is what I led with, which felt right in hindsight.”