Google study analyzes engineering effort to maintain open source packages

Google has released findings from a study evaluating the software engineering hours required to update open source software packages internally. While most updates are completed quickly, the study identifies specific factors that drive update times from hours into months. The research highlights that local patches and dependency counts are better predictors of effort than package age.

Predictors of update complexity

• Most package updates at Google require four hours or less.
• High-effort updates (taking days or months) are better predicted by local patches, customization, number of dependencies, and upstream contributor count.
• Factors like package age or internal usage volume were found to be less effective predictors of complexity.
• The study noted a significant data bias toward the Go programming language.

Why it matters

The study provides empirical data on the hidden engineering costs of adopting open source software in large-scale industrial environments.