It creates a reference repo with git clone --mirror in /var/tmp/git-fastclone/reference for each repository and git submodule linked in the main repo. You can control where it puts these by changing the REFERENCE_REPO_DIR environment variable.
git-fastclone is a tool in the Git Tools category of a tech stack.
git-fastclone is an open source tool with 163 Github Stars and 19 Github Forks. Here’s a link to git-fastclone's open source repository on Github
Here’s a list of reasons why companies and developers use git-fastclone.