If a Git repository does not contain a .gitignore file, hatchling build will search for one in the parent directories. This makes building source distributions for a package inconsistent across systems as an arbitrary .gitignore file can be selected. This could be resolved by avoiding traversal across git boundaries, i.e. limit the search to a single repository or by disabling this behavior by default (in which case, it will probably be enabled in a monorepo with a .gitignore).