Include a systemd.timer file (the interval can be overridden, as
mentioned in the docs). TBH, I'd suggest downstream packagers of
systemd-based distributions include these files on installation
(activation needs to be done manually anyway).
I installed mwic, so you don't have to.
`unperformant` doesn't seem to be an often used english word either and
`addressbook` is probably `address book`.