[dcow]

Smallstep also offers an open source ssh-aware kms-backed certificate authority.

https://github.com/smallstep/certificates

One nice advantage is its support for different provisioning flows. The oauth flavor allows you to hook into an existing identity provider to authenticate certificate requests.

Simply:

    $ step ssh login

and boom you've got a short-lived ssh certificate in your ssh-agent using a private key that never touched the disk.