15 people are the primary owner of at least one file in yamadashy/repomix, and Kazuki Yamada owns the most: 300 files, or 80% of the codebase. The truck factor is 1: that is how few people would have to leave before the majority of owned files lose their owner. 300 files have exactly one contributor, and 8 modules are dominated by a single person.
Engineering-leader view of who owns what: silos, hotspots, dead code, and bus-factor risk by person.