Began styling with bourbon, neat, bitters. Began move to HAML

So I setup erb2haml, but I have to run `rake haml:convert_erbs`. When I run the command I get an error `rake aborted! No rakefile found (looking for: rakefile, Rakefile, rakefile.rb, Rakefile.rb)`

I'm assuming this is because Rake is a Rails used library for tasks and Sinatra doesn't use it?