The jsxbin format (“Binary JavaScript”) is a boon for developers because it enables them to distribute a script without exposing its precious code. The ExtendScript ToolKit (ESTK) offers an Export to Binary feature which instantly converts a human-readable js(x) file into jsxbin. InDesign can then interpret this file as if it were a pure JavaScript. The only (boring!) problem is that the encoded script is not allowed to load a persistent session through the #targetengine directive. Here is a secret trick to bypass this limitation with a single encrypted file.