Atmosphere/AT Protocol login provider for EmDash. Lets users sign in to your EmDash admin with their Atmosphere account — the same identity behind Bluesky and the wider AT Protocol network.

No client secrets, no OAuth-app registration. Users authenticate at their own provider; EmDash never sees a password.

Installation

pnpm add @emdash-cms/auth-atproto

Quick Start

// astro.config.mjs
import { defineConfig } from "astro/config";
import emdash from "emdash/astro";
import { atproto } from "@emdash-cms/auth-atproto";

export default defineConfig({
	server: {
		host: "127.0.0.1", // required for local dev — see below
	},
	integrations: [
		emdash({
			authProviders: [atproto()],
		}),
	],
});

This adds Sign in with Atmosphere to the login page and the setup wizard. With no allowlist, the first user becomes Admin and self-signup is closed for everyone after that.

Configuration

atproto({
	allowedDIDs: ["did:plc:abc123..."],
	allowedHandles: ["*.example.com", "alice.bsky.social"],
	defaultRole: 30, // Author
});

Option	Type	Default	Description
`allowedDIDs`	`string[]`	—	DID allowlist. DIDs are permanent and can't be spoofed.
`allowedHandles`	`string[]`	—	Handle allowlist. Supports leading-wildcard patterns (`*.example.com`).
`defaultRole`	`number`	`10` (Subscriber)	Role assigned to allowed users after the first. First user is always Admin.

If both lists are set, a user matching either is admitted. Handle matches are independently verified against the handle's DNS/HTTP record before being trusted.

Local development

The AT Protocol OAuth profile requires loopback redirect URIs to use the IP literal 127.0.0.1 rather than localhost. Vite (the dev server Astro uses) binds to localhost by default, so set server.host to 127.0.0.1 and visit http://127.0.0.1:4321/_emdash/admin for the whole flow. Otherwise the cookie set on localhost won't be visible after the redirect lands you on 127.0.0.1.

Production

The provider serves its own OAuth client metadata at /.well-known/atproto-client-metadata.json. Authorization servers fetch this URL during login, so your deployment needs to be reachable on the public internet over HTTPS. Set siteUrl if you're behind a TLS-terminating reverse proxy.