Kindlegen
Easy to install kindlegen command via gem.
When you run this gem, it will download a tarball of kindlegen from amazon.com and extract it. Then you can find the command file in "$GEMPATH/bin".
Using from Ruby
Require kindlegen, then run kindlegen commands.
Kindlegen.command
Returns the path of the kindlegen command.
Kindlegen.run(*args)
Runs the kindlegen command with specified parameters.
Example
require 'kindlegen'
stdout, stderr, status = Kindlegen.run("sample.opf", "-o", "sample.mobi")
if status == 0
puts stdout
else
$stderr.puts stderr
end