JetBrains MPS is a state of the art language engineering workbench. See [http://www.openmodeling.nl/jetbrains-mps.html].
From May until October 2016 I worked as a member of the Itemis MPS team in Stuttgart. The Itemis customers I worked for are confidential, so I won't mention them.
The work was focused on developing editors using MPS, especially graphical editors.