I used nostr.build in my app, works just fine!
Discussion
That means obtaining and emplacing an auth key of some kind though, doesn't it? It appears to be paid only and gives me 401s.
It uses a regular nostr key pair, although now that I think of it, I’m using the fileserver, maybe they don’t have a free tier for blossom? I’m not sure how nostr.build handles that.