.git/.graphite_repo_config of your repositiory. On first execution (per repository), or by directly running gt repo init, the CLI will prompt you to provide a minimal amount of info to populate this config (the trunk branch for your development flow).repo init offers the option to add existing branches to Graphite by stacking them onto your trunk branch. Many users will not need this and just use Graphite for new branches — if that is the case, feel free to skip.