$ npm install -g nyc
$ mkdir .nyc_output
$ ./bin/kahlan --istanbul=.nyc_output/coverage.json
$ nyc report --reporter=html --extension=".php"
$ open coverage/index.html

$ brew install lcov
$ mkdir lcov
$ ./bin/kahlan --lcov="lcov/coverage.info"
$ cd lcov
$ genhtml coverage.info
$ open index.html