Atmosphere Mail
Cooperative email infrastructure for atproto. Your domain, your DID, a shared relay that pools sending reputation so you don't have to warm an IP alone.
How it works
Members pool reputation through a shared SMTP relay. Your atproto DID is the identity; a labeling service verifies your DNS and publishes signed verified-mail-operator labels that anyone on the atproto network can read. Every outbound message gets dual DKIM signatures — one aligned with your domain, one pooled across the cooperative — so provider feedback loops route complaints to one place without losing per-member attribution.
What you get
- SMTP submission at
smtp.atmos.email:587with STARTTLS. Drop-in for any app or service that can send email. - Dual DKIM signatures (your domain plus
d=atmos.email) so your messages pass authentication checks and complaints route back to you, not the whole pool. - Public
verified-mail-operatorandrelay-memberlabels on your DID, queryable via standard atproto XRPC. - Warming tier caps for the first 14 days so a new sender cannot tank the shared IP's reputation.
- Replies to mail you send get forwarded back to the mailbox of your choice.
Why not a commercial relay?
Commercial relays work, but your domain's sender reputation lives inside their business. Switching providers means re-warming from scratch. Atmosphere Mail is cooperative infrastructure: the code is open source, the identity layer is atproto, and your sending reputation stays with you.
Where this is, honestly
- Members: any atproto account with a custom domain. Sign in with your DID, prove you own the domain via DNS, and start sending. Works whether you run your own PDS or use a hosted one.
- Relay operator self-hosting: the code is designed for other operators to run their own instance (pluggable notification webhook, configurable operator DKIM domain, Terraform in
infra/). One relay runs today, operated by the project maintainer. Anyone who wants to stand up a second cooperative has a path, and the operator docs are still being written. - Cross-pool federation: multiple relays sharing reputation via a shared blocklist any mail server can check, indexed through atproto. Phase 4 in the roadmap, not yet built.
Today "cooperative" means members pool reputation within one relay. A federation of cooperatives is the direction, not the current state.
Read the longer story, or learn more in the docs.