I think it could be. Cosmos DB might have to be replaced with a different EF Core provider - not sure which would be most appropriate but I’m sure something would work. Key and image storage could just be done on disk.

I’m not exactly sure how it works in wafrn - I haven’t looked into it myself - but last I heard, they were using blacksky’s PDS (https://lemmy.dbzer0.com/post/51892713) which I’m guessing means all their users (at least the ones who’ve turned atproto on) get mirrored to that particular PDS.

The search functionality missing from Pandacap is in some ways intentional; I don’t personally like searching for anything in the fediverse or in Bluesky, because I run into a lot of text posts, photos, screenshots or whatever that I don’t have context for and that I haven’t mentally prepared myself to see. But there’s also the technical issue that right now, Pandacap doesn’t index incoming posts in one place; they either go to the inbox, go to notifications, or get ignored. If search were to be implemented, perhaps it could take the form of an external ActivityPub instance that indexes posts, and Pandacap would just hit its API or something.

The other issues with Pandacap are that it’s single-user, and that it’s on the Microsoft stack, so no one can really use it unless they’re willing to sign up for Azure and know their way around it enough to get it deployed. But that keeps overheads down for me compared to running a VPS.

I’ve never tried loading a PeerTube post in Pandacap but I wonder if it would try (and fail) to display the video in an image tag, or if it would just show up as a text post.

I was recently playing around with Constellation and - partly as a statement but mostly as a personal challenge - used it to build ATProto notifications support into my ActivityPub enabled web app (writeup here, I’d post from that but I think lemmy.world blocks it since I sent it too many invalid activities or whatever).

I already had the ability to follow someone on atproto by resolving their handle and hitting their PDS directly (without authentication - that’s all public), and I also turned Bridgy Fed on. With Constellation, I was able to (a) find the bridged atproto version of each ActivityPub post I made, and (b) find any likes, replies, or reposts related to each post.

When a Bluesky post hits my inbox and I click on it, my app checks to see if that user is also using Bridgy Fed, and if they are, it shows me their post over ActivityPub instead, so I can like or reply to it.

More broadly, it might be interesting if someone made an app that used a PDS as its primary datastore, but also had ActivityPub S2S support built into it. I know wafrn can do both protocols, but I think in its case it mirrors posts to a separate PDS kind of like you’re describing.

The thing with replacing DeviantArt could be interesting. Sites like that - not just DA but also Fur Affinity, Weasyl, etc - have a very different philosophy about how to show your “feed”:

1. there’s always a separation between images and text posts from the people you’re following
2. no reposts - instead each user has a gallery of “favorites” (essentially your likes, but it’s public by default)

These two things are what makes it possible for me to discover artists on sites like these, and why I can’t do the same on Twitter, Tumblr, or Mastodon. The tonal whiplash is just too distressing.

I have made a web app called Crowmask that exposes my Weasyl posts to ActivityPub, but unfortunately it’s one way only for now (and single-user - I’m not prepared to take responsibility for hosting content from someone I don’t know offline).