The Meteor documentation says:
In general, you must specify a package’s version (e.g., ‘firstname.lastname@example.org’ to use version 1.0.0 or a higher compatible version (ex: 1.0.1, 1.5.0, etc.) of the accounts package). If you are sourcing core packages from a Meteor release with versionsFrom, you may leave off version names for core packages. You may also specify constraints, such as my:forms@=1.0.0 (this package demands my:forms at 1.0.0 exactly), or my:email@example.com || =2.0.1 (my:forms at 1.x.y, or exactly 2.0.1).
So just to make sure I understand this:
1.99.999would both match)
firstname.lastname@example.org exactly version
package@=1.2.7- same as above
packagematches anything? (grabs latest version)
I think the documentation could be a little clearer here.