[[!comment format=mdwn
 username="joey"
 subject="""comment 11"""
 date="2020-07-20T18:01:27Z"
 content="""
Wrote a draft [[design/external_backend_protocol]].

I wonder if it makes sense to require the programs to format and parse
their own keys; git-annex could break up the key and send the peices in.
The advantage though is that this lets a program decide whether or not to
include information like the size and mtime fields in the key or not.
And if more fields ever got added it would not need changes to the
protocol. I guess it's simple enough for format and parse, as shown by the
example shell program that does it.
"""]]
