The awesome keyholder service that @faidon requested, @ori created and @thcipriani enhanced allows both MediaWiki and Scap3 deployers to have secure shared access to ssh keys which are used for authn/z by Scap.
The system demon portions of keyholder (keyholder-agent and keyholder-proxy) are currently implemented as Upstart scripts in rOPUP's modules/keyholder. Upstart is not available on Debian Jessie systems which prevents scap deployment masters from being reimaged.