Fabricate
Customize everything.
An alternative for CraftTweaker, in its infancy.
CraftTweaker works with its own language, ZenScript. Fabricate uses Java's built-in API "Nashorn" to use Javascript instead. The API it provides via the Javascript aims to be succinct, expressive, and less obscure. See Scripting to learn how to write scripts for Fabricate.
After the API has matured more, there will be performance tests to compare the speed of Fabricate to CraftTweaker. As of the moment Fabricate is mostly proof-of-concept. It is usable for small-scale pack development, but does not contain the full featureset of CraftTweaker. In time, it will get there.
To see more information, check out the Github repo.
The Fabricate Team
