That&#x27;s the problem AirBnb has right now, according to a friend.  Using Ruby has scaled AirBnb&#x27;s business to great heights.<p>However, it has heaped to performance and code separation of concerns and structure debt. Of course, AirBnb can now afford to move things to Java&#x2F;Scala and things that are better for multinational companies.<p>For AirBnb, it&#x27;s really hard to fix a lot of these things since the product requires good uptime.