How to archive a repo and copy the last n commits to a new one. republik/magazine is used as an example here.
- Ìnstall git script
rebase-from
git config --global alias.rebase-from '!b="$(git branch --no-color | cut -c3-)" ; h="$(git rev-parse $b)" ; echo "Current branch: $b $h" ; c="$(git rev-parse $1)" ; echo "Recreating $b branch with initial commit $c ..." ; git checkout --orphan new-start $c ; git commit -C $c ; git rebase --onto new-start $c $b ; git branch -d new-start ; git reflog expire --expire=all ; git gc --prune=all'