Wikimedia Messages
format = php
desc = Plop
ignored = sidebar, robots.txt
optional = grouppage-recursive-export
prefix = wmf- | sidebar, grouppage-Staff, group-Staff, group-Staff-member
aliasfile = FooBar.alias.php
magicfile = FooBar.magic.php

Example Extension
format = php

Example JsonExtension

Example Extension 2
format = php
file = foo