Supersedes the Go + embed-Mox design. The Go tree is removed; its
architecture doc is preserved at docs/archive/ARCHITECTURE-go-embed-mox.md
because its competitive analysis and data model still hold.
Five decisions recorded as ADRs:
0001 Rust, not Go — accepting ~5,500 lines of protocol code that Mox
would have given us free, to get the first permissively licensed
Rust mail server. Costs stated plainly.
0002 Apache-2.0, not MIT or AGPL — patent grant, trademark, CLA-free
contribution. Public on GitHub; Gitea stays as the private fallback.
0003 Stalwart's primitive crates (Apache-2.0/MIT) yes; its AGPL server
crates never. DANE and MTA-STS sit on the AGPL side of that line,
which is why we write our own.
0004 Milestones, reordered: embedded inbound is required at launch.
0005 Oracle Cloud blocks outbound :25, so direct-to-MX is impossible on
the launch host. Split delivery is mandatory, not an on-ramp.
Twelve crates in three tiers. Tier 1 (mail-dane, mail-mta-sts, mail-dsn)
is standalone and publishable — no `dane` or `mta-sts` crate exists on
crates.io at all today.
openmail-relay ships the provider table as data, with SES and Oracle from
the start. Oracle's and Resend's SPF includes are deliberately None: a
guessed include turns the DNS check green against a mechanism the provider
does not honour, and mail still fails SPF silently.
cargo check/test/clippy/fmt all green; unsafe_code is forbidden workspace
wide; cargo-deny enforces the licence policy in CI.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JkyvfNJGTshJNE9FtwPLk7
Blockers in the ingest path (all funnel real mail in milestone 2):
- H1: coerce body bytes to valid UTF-8 (ToValidUTF8) — non-UTF-8/mid-rune cuts
no longer abort the ingest tx and drop the message.
- H2: EnsurePart's recoverable parse error is non-fatal — proceed with the
guaranteed-usable Part so messy real-world mail is stored, not rejected.
- H3: extractBodies descends into message/rfc822 (Part.Message via
SetMessageReaderAt) — forwarded/bounce bodies no longer lost.
- H4: GetMessage/GetThread/GetThreadMessages scoped to inbox_id — no cross-inbox
access; reply no longer a confused deputy.
Hardening:
- M1: /healthz no longer leaks DB error to unauthenticated callers.
- M2: all DB errors funnel through handleErr; malformed UUID -> 404, dup -> 409,
internal errors no longer echo the driver string.
- M3: index messages(inbox_id, message_id_hdr) for thread resolution.
- M4: pods UNIQUE(name) + ON CONFLICT (name) — no duplicate default pods.
- L1: skip empty-User/Host addresses (no literal "@").
- L2: skip attachment-disposition parts when picking the body.
- L3: case-insensitive, trimmed 'Re:' detection.
Verified e2e vs Postgres 16: latin1 body stored valid UTF-8; rfc822-only body
extracted; cross-inbox 404; malformed UUID 404; dup 409; threading regression OK.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
- Choose Option B: single binary embedding Mox's stateless protocol/crypto/
delivery packages (dkim, spf, dmarc, dane, mtasts, message, smtpclient, junk,
dsn, anti-abuse) while owning server loop (go-smtp) + Postgres data model.
- Boundary rule: never import mox smtpserver/imapserver/queue/store/config
(bbolt/global-config coupled) — that's the line between embed and fork.
- Add MIT LICENSE; reframe README as a real MIT OSS product.
- Deliverability moat leans on mox smtpclient+dane+mtasts; relay fallback.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Design of record for OpenMail — one Go binary (smtpd/core/sender/mcp) + Postgres
+ object storage on a VPS. Covers inbound SMTP/MIME/threading, outbound
deliverability (relay-default, self-host opt-in), data model, AgentMail-shaped
v0 API + MCP server, and an MVP milestone path.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
