Copying

gitto copies the whole directory with the filesystem's clone call, so the copy shares its blocks with the canonical and costs only the metadata. Nothing is excluded and nothing is rebuilt: .git, the submodules, node_modules, the build directory and the untracked local files all come along.

The time a run takes is the number of files, not their size. A 13 GB checkout with several hundred thousand entries takes about twenty seconds; the 2.4 GB prebuilt dependency inside it costs nothing.