Removed and sent pull request:
https://github.com/vyos/vyatta-cfg-system/pull/59
https://github.com/vyos/vyatta-op/pull/10

Well, I have to ask everybody to double think about the very decision to drop the support for "install system" option.
The point is - when you do "install image" - you just drop known-working OS image file to some directory, and if you want to update the OS, you just drop another one (am I correct here?).
But, If you've installed some custom .deb's on the host, you should re-install them after the OS image is updated, even if you had to install new image because of one-line security fix.
Isn't it the scenario for which all those people in debian have used package manager for decades? Isn't it better to just update one package in installed system?

Isn't it the scenario for which all those people in debian have used package manager for decades? Isn't it better to just update one package in installed system?

I think as this is a non general purpose OS there should be no package manager involved at all. Also debian archives have been removed from the nightly builds. If a user want's to update, he can update to a very special released version.
Having users update only some packages will give more trouble during troubleshooting...

I think we should implement a package persistence mechanism at some point. Frankly, APT is notorious for offering conflict resolutions that equal self-destruct, for a network admin who is not an experienced Debian user, installing third-party packages the normal way will create more problems than it solves.