Another project from Jetbrains, their new issue tracker Charisma was written entirely in MPS . Is the concept useful/practical, or is it too soon? MPS isn't just DSLs for Java. It's actually language-angostic. You can generate your language into any other language that is supported by MPS. We support Java, XML, and plain text (as a last resort) out of the box in MPS 1.1. Probably, in future version, we will provide other languages such as javascript, css, etc. One of the key features of MPS which isn't available in other tools is ability to compose languages. You can create several language