Mustache-Highlighting is a project mainly written in ..., it's free.
KDE Kate Text Editor highlighting for Mustache template syntax
To use mustache syntax highlighting in kate:
Save mustache.xml into your kate syntax directory (create the directory if it does not exist) and then restart kate.
Example path:
/$HOME/.kde/share/apps/katepart/syntax/mustache.xml
Don't know what mustache is? See http://mustache.github.com