COMPUTING REWORK CHURN FOR CONTRIBUTIONS TO A CODE BASE

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for generating widened types for computing measures of rework normalized churn. One of the methods includes determining a plurality of commit chains for a software developer. Respective measures of rework churn occurring in each commit chain are calculated. An overall rework factor is computed for the developer using the respective measures of rework churn for each commit chain in the plurality of commit chains for the developer. A measure of rework normalized churn is computed for the developer including adjusting the initial measure of churn by the overall rework factor. Productivity of the developer is quantified relative to one or more other developers using the measure of rework normalized churn for the developer.