[callahad]

The source is pretty easy to read. Here's how it's working: https://github.com/gaubert/gmvault/blob/master/src/gmv/gmvau...

(It stores each mail in two separate files: a .eml file with the message body, and a .meta file with metadata.)

[zoobert]

I will take that as a compliment. Yes files are all stored individually as .eml file. All the extra Gmail info (labels, ...) goes in .meta