No, they are referring to an application that is being moved from MySQL to PostgreSQL. The application is &quot;legacy&quot; in that it is an older version and the new version is &quot;current&quot;.<p>Due to the English language however there can be some debate as to what they meant. In this case &quot;legacy&quot; is most likely meant to describe the &quot;MySQL application&quot; not &quot;MySQL&quot; itself.