Please see comment from Antonio Rojas
It’s not a development version. That message is displayed because the package is built from the git repo, not from a released tarball.
– cryfs development version, do not use in production? / Newbie Corner / Arch Linux Forums
Apparently the Arch Linux maintainer rebuild using the git source instead of a release tag - although the Arch Linux PKGBUILD reference the release tag - nothing we can do - it is how it 