Sensitive information is stored in a "walled garden", an encrypted keybase git-submodule. But couldn't combine existing repo with it, due to GitHub's jekyll complains, as explained in foam. So it has to happen in 2 steps: clone and attach submodule locally only.
Command to attach my walled Garden:
git submodule add -f keybase://private/ankostis/GardenWall Walls
-f is needed because
.gitmodules is in
for it must not be pushed to GitHub repo.