[Nitro] OG automatically adding Foreign Key constraints

[Isaac Devine]

Hi,

When using belongs_to and has_many Og isn't generating Foreign Key
Constraints :

class Example1
 property :name, String
 has_many :children, Example2
end

class Example2
 property :address, String
 belongs_to :parent, Example1
end

What am I doing wrong? 
Failing that is there a way I specify the constraints?

thanks,
Isaac