This unique, in-game, Tinkerer Certificate decoration is included as a basic reward in the Developer pledge tier.

The certificate's Runic Translation:
The Mercantile Guild of New Britannia
has Been graciously pleased By Warrant Order for signet and sign
to ordain and declare that the bearer of this certificate shall henceforth
have hold and enjoy all the preeminence and precedence of
a tinkerer of New Britannia, recognized as a master tinkerer Novia.
And we instruct all officers of the mercantile guild
to recognise the bearer as such in all their future endeavors.