Google: patches and dependencies make open source updates costly

Google studied the engineering effort behind 54 updates to its internal copies of open source packages between April and December 2024. The median update took 2.2 engineering hours, the average 13.9 hours, and one update required an estimated 400 hours. Packages with company-specific patches took three times longer at the median.

• Median update effort was 2.2 hours, average 13.9 hours
• Packages with company patches took 3x longer at the median
• One update required an estimated 400 engineering hours
• 52 of the 54 packages were written in Go