Get security and peace of mind by backing up your Google Apps Script files to Google Docs and trigger for continuous backup.
We’ve featured a couple of methods for restoring Google Apps Script code in Pulse, but most of these rely on recovering a deployed version of the script. Stéphane Giron wields his Apps Script hammer and skilfully demonstrates how you can use Google Docs and it’s built-in version history as a way of keeping a backup copy of your code.
Source: Quick and not so Dirty backup solution for Google Apps Script Code
Member of Google Developers Experts Program for Google Workspace (Google Apps Script) and interested in supporting Google Workspace Devs.