Originally I planned to publish PG packaged as a Chrome app. I spent a lot of time working around Chrome App API security limitations and complicated way of accessing the file system.

Then I found node-webkit. I had PG working in a couple of hours. Using Node.js fs module for file access is almost trivial. In general I try to keep core JS code not tied to Node.js or anything else. PG uses Node.js part of node-webkit only for file access, menus and clipboard. Everything else happens in a browser (embedded Chromium in this case). It would be easy to port PG to another JS-based platform, like atom shell.

Hope this helps.