Customizing Jenkins on start up - Initialization Scripts

[RM]

Hello,

I am looking for options to customize Jenkins after start up. For e.g. set up tools such as Java, Git, Maven, etc.

While i do see the option of writing groovy scripts and placing them at $JENKINS_HOME/HOOK.groovy.d, I would prefer to read the tool locations (in my groovy file) from a YAML configuration and load them dynamically..

Is there a way i can read environment variables in these init scripts? Or through YAML Beans?

Any pointers will be much appreciated. I am planning to use the Jenkins docke images

Regards,

Z