Calculate the relative long-term impact of each individual developer based on git history. This is a score based on the surviving lines of code contributed by each developer; a surviving line of code is one that is still present in the current main branch.
Older code can be considered more valuable because it has passed the test of time and it has been providing value in production for longer, some strategies to account for this are available. The absolute score is meaningless, the only value is in comparing scores between developers. Consider using a normalised result if you want to compare scores across repositories.
Multiple factors can affect the validity of the score (technical debt, development practices, etc.), so take these results with a pinch of salt.
To learn more read the article and/or watch the presentation.
mvn clean verify
java -jar target/developer-legacy-index-1.0-SNAPSHOT.jar [weight-strategy] [--normalise-result] [--group-by-name] repository-path
where
weight-strategy is one of:
--no-weight(default): no weight applied, all surviving lines of code are worth the same.--linear-weight: the value of a surviving line increases linearly with age.--exponential-weight: the value of a surviving line increases exponentially with age.
--normalise-result (optional): make the highest score 1 and adjust all other scores accordingly.
--group-by-name (optional): group contributions using the developer's registered name, as opposed to their email (default). This is useful
if the developer changed their email at some point during git history (but kept name intact).
repository-path: relative or absolute path to a local git repository.