Home | Notifications | New Note | Local | Federated | Search | Logout

Note Detail

andros@andros@activity.andros.dev (2026-07-27 17:28:50)
«Modern email can be built from borrowed parts»

What if we designed the successor to email on top of HTTP, fixing 40 years of SMTP design flaws using only technologies that already exist?

https://en.andros.dev/blog/d7ed8b07/modern-email-can-be-built-from-borrowed-parts/

#Email #ActivityPub #OpenWeb #Python
---Reply---
Blurry Moon@sun@shitposter.world (2026-07-27 20:34:11)
@andros are all your attachments public? Content addressed Hashimg doesn’t have privacy or deniability

---Replies---

andros@andros@activity.andros.dev (2026-07-27 22:06:26)
@sun Good question: Fair, but two separate things.
Deniability: correct, and intentional; HMTP trades deniability for unforgeable authenticity, you can't have both at once (same tradeoff signed PGP/S-MIME always had).
Attachment privacy: valid gap as written. The {hash, url, size} scheme doesn't say the bytes are encrypted before storage, so as described, anyone with the hash+URL could fetch them.
Fix is the same trick used for the body: seal the attachment client-side with the same X25519 sealed box before upload, so the hash addresses ciphertext, not plaintext (what Signal/Matrix do for media). Worth noting attachments aren't in the working prototype at all yet… this part was design-only. Please be understanding, I wrote it on Sunday afternoon while having a coffee. 😄