LuaLibraries are part of the phones configuration. You can create your own, be it self-written or copy-pasted open source code. Just adapt the following and include it to your provisioning or simply restore it as backup via the WebUI. You can then use this library in any lua-script by requiring it, e.g. local myLib = require “myFancyLibName”

<luaLibraries>
    <luaLibrary name="myFancyLibName">
      <code><![CDATA[
-- insert your lua code of your library here
      ]]></code>
    </luaLibrary>
</luaLibraries>