nostr:nprofile1qqsqgc0uhmxycvm5gwvn944c7yfxnnxm0nyh8tt62zhrvtd3xkj8fhgpzamhxue69uhhyetvv9ujuurjd9kkzmpwdejhgtcpzemhxue69uhhyetvv9ujuerfw36x7tnsw43z7qgkwaehxw309aex2mrp0yhx6mmnw3ezuur4vghs0klf00 made an interesting proof of concept recently with Cloudflare that could deploy a nostr relay to Cloudflare workers. Perhaps you could go that route? You'd just need to add a config item to add an env variable for the user's pubkey and figure out billing.