Which DKIM application for postfix 3.9.0

I am upgrading to postfix 3.9.0.

I have not used DKIM in previous postfix installs, but I would like to start now with the new google rules.

I have done some research and opendkim is the most recommended, however, other research states the opendkim has been abandoned by it's maintainers.

So I am looking for a good alternative dkim software that will work with postfix that I can compile myself.

I do not run on any linux version, so therefore I can not just apt-get a new dkim application.

I run Solaris and therefore need to compile my applications, postfix and dkim.

Any good suggestions will be appreciated.