I've been searching for a clear method to create a custom Netinstall image of Sierra for a while without success.
My goal is to have two administrator accounts by default and some packages (e.g. Slack, Firefox, iTerm2 ...) incorporated with the installation.
I've tried different methods.
AutoDMG - Automator method:
I successfully create the dmg image with autoDMG (I mounted it and effectively I have Firefox and stuff in the Application folder). Then I create a custom Netinstall image with Automator (adding the users in the workflow) and install it on another mac, but finally the packages are not in the OS and not even the users, I have a simple OSX installation.
Packages - Automator method:
I create a package including Slack, Firefox, iTerm with Packages App (by Apple) and include it with Automator in the Netinstall image. But this way the installation fails because the package is not signed by a verified Apple developer (obviously ...).
So, I admit I'm pretty desperate. I spent a lot of hours trying to figure it out.
Any help would be appreciated! Thanks
UPDATE
I was wondering if it is possible to include a script in the installation that will be lauched at the first boot to perform some actions like enabling ssh and/or enabling and configuring filevault. This will prevent me of shaping an image with packages included as I would install Munki (github.com/munki/munki) and then allow users to get packages easily.
Hope I was clear enough.