<li>free & open-source (AGPL), you can use it your own, in your company, at your university, etc. (git repo: <tt><a href="#{browsableGitRepo "gonito"}">git://gonito.net/gonito</a></tt>),
<li>git-based (challenges and solutions are submitted only with git).
<p>Gonito uses <a href="https://developer.mozilla.org/en-US/Persona">Persona</a> authentication system available in Mozilla Firefox. Other authentication systems are on the way, but for the time being you need to use Firefox.