Been repairing broken languages since god made dirt. Best known for adding OOP to C, producing Objective-C. Current project is repairing XACML by compiling it to Java and potentially Scala.
XACML is a simple functional language used for access control that is wrapped in the most god-awful XML-based syntax you could possibly imagine. Visual barbed wire that makes your eyes bleed. The generated Java is much easier to read, works in debuggers, and runs 10x to 500x faster depending on exactly what is measured. See http://bradjcox.blogspot.com for more on that.