The owner's "проверь, что документация актуальна с кодом" (2026-10-16).
Read-only reviews checked every present-tense claim against the code;
each finding was read in the source before it was fixed here.
architecture.md: held inbound mail has its row from the journal milter,
not the tailer; the antispam action is accept or tempfail, anything else
stops the start; tls-internal's certificate is 0644; the signer logs to
stderr; the log's fingerprint is the inode, not the device; a mail.log
postlogd makes is 0640 (maillog_file_permissions); an unreadable stored
place starts at end-of-file too; the test-message route; no map in page
data; design-first compares whitespace aside; the queue and sasldb2.new
are not backed up; antispam/ under /data; POSTFIX_QUEUE_DIR's desync;
SELFPOST_BACKUP_PASSWORD (the CLI's).
schema-migrations.md: inbound_spam_log's upstream columns (v12),
send_log's sender reason, row 9's client_ip.
security.md: /data/opendkim since 2.9.0 (removed, or the start refused),
sasldb2 under /data/sasl, the trigger for mandatory encryption, the
password minimum counted in characters.
development.md: Staticcheck in CI, the e2e ports 20025 and 20053/udp.
README: the client IP list refuses at MAIL FROM, overrides are per
application. product.md: the optional rspamd sidecar.
Code: validate.AdminPassword counted bytes, so six Cyrillic letters
passed for twelve characters; it counts runes, as the backup password
always did (TestAdminPasswordCountsCharacters). envdoc reads
cmd/selfpost-backup too, and a name kept in a constant. A stale comment
of cmd/panel's run ("three roles").
go vet + go test (26 packages) and make e2e on the test server for this
tree.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
127 lines
5.0 KiB
Markdown
127 lines
5.0 KiB
Markdown
# SelfPost — product boundaries
|
|
|
|
**What this file is.** Stable product definition for SelfPost v1.0: purpose,
|
|
deployment assumptions, explicit out-of-scope items, and the multi-domain
|
|
model. User-facing overview in [README.md](../README.md); install and operations
|
|
in [guide.md](guide.md); as-built technical detail in
|
|
[architecture.md](architecture.md).
|
|
|
|
---
|
|
|
|
## Purpose
|
|
|
|
SelfPost is a self-hosted **SMTP relay** with a web control panel, shipped as a
|
|
single Docker image. It sends mail directly from your server with per-domain
|
|
DKIM signing; an optional inbound relay forwards mail on port 25 without
|
|
storing it.
|
|
|
|
**Primary workflow:** configure the relay once (domains, DKIM, SASL
|
|
applications), then point scripts and apps at the SMTP endpoint. SelfPost
|
|
delivers as the configured sending domain.
|
|
|
|
## Positioning
|
|
|
|
| | Text |
|
|
|---|---|
|
|
| Stamp subtitle | SELF-HOSTED SMTP RELAY |
|
|
| Wordmark | The stamp's own letter outlines without the stamp (`docs/assets/selfpost-wordmark.svg`, `-ink` for light grounds) — for places too small for the stamp, such as the panel header |
|
|
| Tagline | YOUR SMTP. YOUR RULES. |
|
|
| Hero line (README, GitHub) | Self-hosted SMTP relay with a web panel — one Docker image, no provider. |
|
|
|
|
Brand assets and metrics: [docs/assets/selfpost-proof.html](assets/selfpost-proof.html).
|
|
|
|
---
|
|
|
|
## Deployment context (fixed assumptions)
|
|
|
|
These constraints are intentional; changing them requires an explicit product
|
|
decision:
|
|
|
|
1. **VPS or home server** — one image for both. Raspberry Pi and similar boards
|
|
are not a current target but not ruled out forever.
|
|
2. **Send from your own IP (DIY)** — no intermediate relay provider. Requires
|
|
outbound port 25, static IP, and configurable PTR/rDNS from the operator.
|
|
3. **Single container** — Postfix and the panel, which signs outgoing mail
|
|
with DKIM itself, run under one `supervisord` inside one image.
|
|
4. **Panel is internet-facing** — mandatory security requirements in
|
|
[security.md](security.md).
|
|
|
|
**Infrastructure the operator provides (not SelfPost features):** unblocked
|
|
outbound TCP 25, static IP, PTR/rDNS, acceptable IP reputation. SelfPost does
|
|
not detect, bypass, or compensate for missing prerequisites; mail simply fails
|
|
to deliver when they are absent.
|
|
|
|
---
|
|
|
|
## Out of scope
|
|
|
|
Explicitly excluded to prevent scope creep:
|
|
|
|
- Inbound mail (IMAP/POP3, mailboxes, delivery to user inboxes)
|
|
- Webmail
|
|
- Organisations / tenancy beyond the `global` and `domain` roles; managing
|
|
**multiple sending domains** under one global administrator is in scope (see
|
|
below)
|
|
- Inbound antispam/antivirus engines (rspamd, ClamAV, etc.) — the image
|
|
ships no filter, only a milter hook; `deploy/antispam` offers an optional
|
|
rspamd sidecar that the panel's filter lists feed
|
|
- A custom MTA — Postfix is used as-is
|
|
- Dovecot or a full mail stack for SASL — Cyrus SASL (`sasldb2`) only
|
|
|
|
The **`domain`** role ships in the current line (a `global` user plus
|
|
`domain` users with assigned domains, outbound and inbound separately). The
|
|
optional **inbound relay** (backup-MX / forwarder on port 25) ships in `[1.4.0]`, off by default behind
|
|
`INBOUND_RELAY_ENABLE`; it is relay/forward, not IMAP/webmail. **Send-log
|
|
retention in Settings** ships in `[1.5.0]`. **30-day send statistics** and
|
|
**auto level-2 rate limits** ship in `[1.6.0]`. **DMARC aggregate report
|
|
ingest** ships in `[1.7.0]`, off by default behind `DMARC_REPORTS_ENABLE`.
|
|
Items marked *candidate* in the
|
|
[roadmap](roadmap.md) require explicit approval before coding.
|
|
|
|
---
|
|
|
|
## Multi-domain model
|
|
|
|
SelfPost is a **multi-domain outbound relay**. Two linked entities:
|
|
|
|
### Sending domain
|
|
|
|
Example: `example.com`. Has its own DKIM key and selector.
|
|
|
|
### Application (account)
|
|
|
|
A SASL login/password bound to **one** domain. A domain may have several
|
|
applications (e.g. newsletter vs alerts), each with its own credentials, but
|
|
each may send **only from its own domain**, never from another.
|
|
|
|
### From-address mode (per application)
|
|
|
|
Set when creating or editing an application:
|
|
|
|
1. **Any address in the domain** — `*@example.com` (wildcard in
|
|
`smtpd_sender_login_maps`).
|
|
2. **Explicit address list** — only listed From addresses within the domain;
|
|
anything else is rejected even if it belongs to the same domain.
|
|
|
|
In both modes the From address must belong to the application's domain.
|
|
|
|
### What the panel manages per domain
|
|
|
|
- DKIM key + selector (shared by all applications on that domain)
|
|
- One or more applications (SASL credentials + From mode + optional rate limits)
|
|
- DNS guidance (DKIM TXT; reminders for SPF/DMARC)
|
|
|
|
Adding a domain does **not** create an application automatically.
|
|
|
|
### Lifecycle
|
|
|
|
- **Add domain** — record, DKIM key, DNS instructions; no application yet.
|
|
- **Add application** — SASL pair (password shown once), From mode, map entries,
|
|
`postfix reload`.
|
|
- **Delete domain** — removes DKIM key and **all** its applications.
|
|
- **Delete application** — removes only that app's SASL and map entries.
|
|
|
|
This is not multi-tenancy; it is one owner (or a small team with global and
|
|
domain-scoped roles) operating several sending domains with independent
|
|
application credentials.
|