[tsileo]

I don't want to have a running process just for this, I want to be able to take a "snapshot"/"index", store some data on Glacier, and the index on S3, and later, given the index, be able to compute deltas without accessing the full archive store on Glacier.

[blueblob]

Is there a reason that you want it in python? Couldn't you do this with diff -q if you only want to know what data has changed? and then use diff to get the deltas?