There is an answer to my question (thanks @Ryan), but it has a caveat. Yes, Anypoint Studio is open source, but comes with an Enterprise runtime by default. You can download Community Edition (CE) and use Anypoint Studio with this.
However, a caution is the time it takes to configure a stream with the DataMapper enabled. When I tried to start my thread with the community editors, I received the following error. Basically, to run a thread using DataMapper, you need an Enterprise version. DataMapper is not running with CE.

source share