GoToSocial docs are tripping me up on Greater Fediverse Theory. They say:

It's not supported across the Fediverse to switch between implementations on the same domain. This means that if you run GoToSocial on example.org, you'll run into federation issues if you try to switch to a different implementation like Pleroma/Akkoma, Misskey/Calckey etc.

This to me seems to say that I can stay within a software "family" and maintain federation - like I could go from Misskey to Calckey and be fine, but not Misskey to Mastodon?

And in that same vein, can I switch between GTSocial, Mastodon, and Glitch without messing up domain federation?

I suppose it make sense you can since glitch-soc requires you to have a working Masto instance first. Just trying to find the line between software and protocol I think

@kayleeserenada protocol-wise you can run whatever you want as long as it's an http server that can respond to requests when everyone else wants to fetch old activities and objects

software-wise, pretty much no one puts those activities and objects into file storage, they put them into a database, and the way they put them into the database is different for every single software.

within a family of forks, it's usually not very hard to migrate the database formats, but across software, it is.

@kayleeserenada so for example, you can start on mastodon, and moving to glitch is just a matter of your database migrations adding or removing a few fields or properties here or there.

but moving mastodon to gts or mastodon to misskey would be a lot harder, because those softwares have completely different database formats, so you have a lot of work to do if you want to convert data.

the data conversion process is often known as ETL - "extract, transform, load". you end up recreating a new db

@kayleeserenada more precisely, you extract data from the old database, transform it from the old format into the new format, and then load it into the new database.

as it stands currently, no one has written scripts or tools to do this work that i'm aware of.