Two quick-reference documents, written to be scanned rather than read: - USER-GUIDE.md for people new to IRC -- connecting, claiming a nickname, the dozen commands that matter, scrollback, and a plain-language privacy section (cloaked IP, channels logged for the configured retention, how to turn off DM storage). - ADMIN-CHEATSHEET.md split by where you work: from IRC as an operator (UBAN, KILL, DEFCON, ChanServ, NickServ) and on the host via ergoctl, plus mode tables and a "when things go wrong" section. Both use the same placeholder convention as ergo.motd and are rendered by deploy.sh into $STACK_DIR/docs/ with the network's real name, domain and retention, so they can be handed straight to users and moderators. Refreshed on every run, like the other installed files. Command and mode references were checked against the v2.19.1 sources rather than written from memory: irc/modes/modes.go for every mode letter, and irc/chanserv.go and irc/nickserv.go for the service subcommands and which require an oper capability. build.sh's embed guard caught the docs being added to FILES without being added to deploy.sh's EMBEDDED manifest -- the exact failure it was added to prevent. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
ergo
Ergo — a modern IRC server with built-in services
(NickServ/ChanServ/HostServ), message history, always-on "bouncer" clients and
IRCv3 — behind Caddy for automatic Let's Encrypt TLS. Ships a host CLI
(ergoctl) for day-to-day administration and a health-checked updater
(update.sh) that also keeps Ergo's TLS certificate in sync with Caddy.
Docker, not an OpenRC/systemd service
Ergo is a single static Go binary, so a native install is perfectly possible. This stack still uses Docker Compose because it matches the repo's goals better:
| Docker (this stack) | Native OpenRC / systemd | |
|---|---|---|
| Alpine, Debian, Alma | one compose file, one image | Alpine packages ergo in community, but a stable branch keeps the version it shipped with (3.24 → 2.18.0, 3.23/3.22 → 2.16.0) while upstream is at 2.19.1, a security release; only edge tracks upstream. Debian/Alma have no package at all → hand-rolled tarball install + a unit per init system |
| Upgrade / rollback | ERGO_TAG in .env, health-checked, DB snapshot, rollback |
replace a binary + hand-restore the DB |
| ACME TLS | stock Caddy (already used by every other stack) | certbot/acme.sh per distro + deploy hook |
| Real client IPs | yes — host networking (see below) | yes |
The usual objection to containerised IRC — bans, throttling and IP cloaking
need the client's real address, and Docker's userland proxy hides IPv6 clients
behind the bridge gateway — is solved by running both containers with
network_mode: host. That also means the host's deny-by-default firewall
genuinely governs the ports (the "Docker bypasses INPUT" caveat from the root
README does not apply here).
Topology
| Port | Who listens | Purpose |
|---|---|---|
6697/tcp |
Ergo | IRC over TLS (Let's Encrypt cert, copied from Caddy) |
443/tcp |
Caddy | wss://DOMAIN/webirc → Ergo's websocket listener on 127.0.0.1:8097; text landing page at / |
80/tcp |
Caddy | ACME HTTP-01 + redirect to HTTPS |
127.0.0.1:6667 |
Ergo | loopback plaintext: compose healthcheck + ergoctl (exempt from ip-limits/bans, treated as secure) |
6667/tcp public |
Ergo | only with PLAINTEXT=1 (STS is then advertised) — not recommended |
No HTTP/3 (would bind udp/443), Caddy's admin API is off (it would sit on
the host's loopback), and there is no ports: section — host mode.
Required .env values
| Variable | Notes |
|---|---|
ERGO_DOMAIN |
Public hostname (lower-case). Server name, cert subject, Caddy site and websocket origin. Immutable after the first deploy. |
ACME_EMAIL |
Let's Encrypt registration email. |
NETWORK_NAME |
IRC network name (letters, digits, . _ -; no spaces). Defaults to ERGO_DOMAIN. |
ERGO_TAG |
Pinned image tag with the v (v2.19.1). Set by deploy.sh to the newest release; bumped by update.sh. Never stable/latest — if a first deploy could not reach GitHub it falls back to stable, and the next update run pins it. |
PLAINTEXT |
0 (default) or 1 — public plaintext 6667. Fixed at the first deploy (it selects a listener in ircd.yaml, which deploy.sh never rewrites); see below to change it. |
HISTORY |
sqlite (default) / postgres / off — see Message history. |
UPDATE_POLICY |
latest (default) / security / off — see Updates. |
See .env.example for the rest (UPDATE_GRACE,
FORCE_UPDATE, CADDY_AUTOUPDATE, CADDY_TAG). .env must not contain $
(Compose interpolates it) — secrets never live there. The four update knobs are
read from .env by the scheduled jobs; an environment variable, or a value
pinned in /etc/ergo-update.conf, overrides it for that run.
Deploy-time-only options (not stored in .env): ERGO_AUTOUPDATE=0 installs
update.sh without scheduling the daily update (cert sync is still scheduled),
and CERT_WAIT (default 180s) bounds the wait for the first Let's Encrypt cert.
To switch PLAINTEXT after the first deploy: change the plaintext listener with
ergoctl edit ("127.0.0.1:6667": ↔ ":6667":, and server.sts.enabled with
it), set PLAINTEXT in .env, run ergoctl restart, then re-run deploy.sh
so the host firewall matches. Passing a conflicting PLAINTEXT= to a re-run
stops with those instructions rather than half-applying the change.
Deploy
./automations.sh # Deploy on this host → deploy: ergo
Or build + run the self-contained artifact:
./build.sh
scp deploy.sh root@host:
ssh root@host 'bash deploy.sh'
# non-interactive:
# ERGO_DOMAIN=irc.example.com ACME_EMAIL=me@example.com NETWORK_NAME=MyNet SKIP_PROMPTS=1 bash deploy.sh
Unattended provisioning: cloud-init.yml. On first run
deploy.sh:
- installs Docker (+
openssl,jq,curl) and creates theergosystem user the container runs as; - registers
80,443,6697/tcpwith the host firewall (/etc/firewall/ports.d/ergo.rule, or ufw/firewalld); - pins
ERGO_TAGto the newest release and seeds.env; - generates
ircd/ircd.yamlonce, from the pulled image's owndefault.yaml(so it always matches the running version): server/network name, the listeners above, the websocket origin, the cloak suffix, and anadminoper whose random password is saved tosecrets/admin.pass(0600; only the bcrypt hash goes into the yaml). Hard post-checks refuse to continue if the upstream template layout ever changes under the edits; - validates the config with
ergo run --smokein a throwaway container before anything starts, validates the Caddyfile, then starts the stack and waits for both healthchecks (Ergo's is IRC-level: aQUITmust be answered withERROR); - waits for Caddy's Let's Encrypt cert, copies it into
ircd/and rehashes Ergo (until then Ergo serves a self-signed cert from its ownmkcerts); - schedules
update.sh certsyncevery 15 min andupdate.sh rundaily (ERGO_AUTOUPDATE=0schedules only the cert sync).
Re-runs are idempotent: they never touch ircd/ircd.yaml, secrets/ or
caddy/etc/conf.d/, and they adopt the deployed settings from .env rather
than this shell's defaults, so a plain bash deploy.sh cannot silently close a
PLAINTEXT=1 firewall port or reset your update policy. A setting you do pass
explicitly is written back to .env. A changed Caddyfile triggers a Caddy
restart, since Caddy has no admin API here.
Administer: ergoctl
Installed at /usr/local/bin/ergoctl. It talks to Ergo over the loopback
listener as the admin oper.
| Command | What it does |
|---|---|
ergoctl status / users / logs [-f] / version |
health, versions, TLS state, user count; server log with health-probe noise filtered |
ergoctl edit / motd |
$EDITOR on ircd.yaml / ergo.motd, then validate (throwaway container) and REHASH; the previous file is restored if either step fails |
ergoctl rehash |
reload config, MOTD and TLS certs without disconnecting anyone |
ergoctl restart / stop / start |
restart the container (drops every user; needed for settings Ergo fixes at startup, such as server.name, datastore.path, casemapping, enforce-utf8, max-line-len, idle-timeouts). Changes to docker-compose.yml or .env need docker compose up -d instead |
ergoctl oper list|add|passwd|certfp|rm |
manage operators in ircd.yaml; passwords are generated (24 chars) and printed once. See Operators |
ergoctl passwd [show|rotate] |
the admin oper password |
ergoctl announce <text> |
NOTICE to everyone |
ergoctl kill <nick> [reason] · ban add|del|list|info · defcon [1-5] |
moderation (UBAN under the hood). ban add takes an IP, CIDR, nick!user@host mask, or account name — a bare name is an account to suspend, not a connected nick, so run ban info <nick> first to get their IP |
ergoctl cmd <raw IRC line> |
anything else as the admin oper, e.g. ergoctl cmd NS SAREGISTER alice hunter2, ergoctl cmd CS PURGE ADD #spam (CS PURGE DEL to undo); replies are printed with control characters stripped |
ergoctl cert [show|sync] |
cert on disk vs the one served on 6697; force a sync |
ergoctl backup [--live] [dir] / restore <file> |
see Backups |
ergoctl update … |
passthrough to update.sh |
ergoctl history [backend] |
show or switch the persistent-history backend |
ergoctl debug on|off · caddy-restart · shell |
log level; apply Caddyfile/conf.d changes; a shell in the container |
Editing by hand works too: change ircd/ircd.yaml, then ergoctl rehash — a
rejected config leaves the old one running (Ergo's rehash is transactional), but
the file on disk would then be unbootable, which is why ergoctl edit
validates first. Ergo's manual
covers every option; the pristine template for your version is in templates/.
TLS
Caddy owns the ACME account and renews the cert on its own schedule (ARI-driven).
Ergo terminates TLS itself on 6697, so the cert has to reach ircd/fullchain.pem
privkey.pem.update.sh certsync(every 15 minutes, via busybox crond or a systemd timer) does that the way upstream's certbot deploy-hook recipe does, plus safety checks:
- picks the newest
<domain>.crtundercaddy/data/caddy/certificates/*/(Let's Encrypt or the ZeroSSL fallback), skipping a renewal that is still mid-write; - verifies the key matches the cert (certmagic writes them as separate files and
generates a new key on every renewal), stages both in
ircd/and installs them with two atomicmvs — Ergo never sees a half pair, which would be fatal at its next start; SIGHUPs Ergo (rehash swaps the TLS config for new connections only) and confirms the fingerprint served on 6697 changed; if not, the previous pair is restored and you get an ntfy alert.
Silent when nothing changed. The daily run also warns when the served cert is
still self-signed (DNS/80/443 not right yet) or expires within 14 days
(certsync not running). ergoctl cert shows both sides.
Operators
An oper name is a credential, not a nick — you authenticate as one and keep
your own nickname. Deploy creates admin (class server-admin, hidden: true),
whose password is in secrets/admin.pass (ergoctl passwd show):
/OPER admin <password>
Add your own rather than sharing that one. Ergo casefolds oper names, so use
lowercase letters, digits, _ and -, starting with a letter:
ergoctl oper add alice server-admin
The class is chat-moderator by default; server-admin adds rehash, account and
channel administration, defcon and massmessage.
Client-certificate auth
Instead of typing a password every session, an oper can be identified by the
SHA-256 fingerprint of their TLS client certificate. Find it on the 276 line of
your own /WHOIS, or from the certificate:
openssl x509 -noout -fingerprint -sha256 -in client.pem
Then pass that fingerprint, or let ergoctl read it off a connected user:
ergoctl oper certfp alice 57_Wolve --auto
Without --auto, Ergo requires both the certificate and the password, which
makes the certificate a second factor. With --auto the password is removed and
the certificate alone grants operator status the moment they connect — nothing
typed, nothing replayable, but anyone holding that key is an operator on sight.
ergoctl oper certfp alice --clear revokes it.
This is refused for admin, deliberately. ergoctl opers up over the
loopback plaintext listener, which presents no client certificate, so a certfp
there would make Ergo reject it — and every ergoctl command needing oper,
including the scheduled jobs, would stop working. Keep admin on its password
and put certificates on personal opers.
Message history
Ergo keeps channel and DM history for CHATHISTORY, /HISTORY, autoreplay-on-join
and always-on (bouncer) clients. Upstream keeps it in RAM, so it is lost on
every restart — including the ones this stack's updater performs. So persistence
is on by default here:
HISTORY |
What it does |
|---|---|
sqlite (default) |
A file at ircd/ergo_history.db, next to the account database. No extra container, backed up with everything else. Right for a single-node server. |
postgres |
A pinned PostgreSQL container (docker-compose.postgres.yml), reachable only on 127.0.0.1. Choose it if you want a real database to query, or already run Postgres. |
off |
Upstream behaviour: RAM only. |
Both SQL backends need Ergo 2.18.0+ (deploy.sh refuses older pins). How long
messages are kept is history.restrictions.expire-time in ircd.yaml — one
week by default — not a size limit: enabling persistence removes the in-memory
channel-length/client-length caps. Raise or lower it with ergoctl edit, and
note the privacy point upstream flags: persisted messages are personal data, so
check what your jurisdiction expects of you before extending retention.
ergoctl history # backend, database size / connectivity, retention
ergoctl history postgres # switch (restarts Ergo; does NOT migrate messages)
Switching backends leaves the old store on disk and starts the new one empty — there is no migration path, so pick one at deploy time if you can.
PostgreSQL
HISTORY=postgres adds docker-compose.postgres.yml to COMPOSE_FILE in .env,
which docker compose reads by itself — so every command in this stack sees the
same services with no extra flags. The container publishes only to
127.0.0.1:5432, Ergo reaches it there (the host-networked containers cannot
use compose service DNS), and depends_on: service_healthy keeps Ergo from
starting before the database accepts connections. The password is generated into
secrets/postgres.pass (0600) and passed via POSTGRES_PASSWORD_FILE, so it
never lands in .env.
The major version is pinned and the updater never touches it. PostgreSQL
refuses to start on a data directory written by a different major version, so
moving from 17-alpine to 18-alpine is a deliberate dump-and-restore:
ergoctl backup # contains a pg_dump of the history database
ergoctl history off && docker compose down -v postgres # drops the old data volume
# set POSTGRES_TAG=18-alpine in .env, then:
ergoctl history postgres && ergoctl restore backups/ergo-backup-<ts>.tar.gz
Note that Postgres 18 also changed the image's default data directory layout; the
compose file pins PGDATA explicitly so a future image default cannot move it.
Updates
ergoctl update check # running vs latest, published security advisories, cert state
# reports only, with one exception: a floating ERGO_TAG
# ('stable') is pinned to the running version in .env
ergoctl update update # update now (TARGET_VERSION=2.19.1 to pin); honours the safety rails
ergoctl update install # (re)schedule / uninstall to stop
UPDATE_POLICY (in .env) drives the daily run:
| Policy | Behaviour |
|---|---|
latest (default) |
Update to the newest release whenever one exists. |
security |
Update only when a published GitHub security advisory covers the running version, or a release since it has a ### Security section in its notes (upstream only opened GHSAs from 2.19.1). |
off |
Never change the running version (check/notify only). |
Every update, scheduled or manual:
- pulls the pinned
ghcr.io/ergochat/ergo:vX.Y.Zand pre-flights it against a copy ofircd/(ergo run --smoke— also dry-runs a DB schema upgrade); NOTICEs connected users and waitsUPDATE_GRACEseconds (default 60);- stops Ergo and snapshots
ircd.dbtobackups/(consistent copy; buntdb is append-only, so a live copy could miss the last second), keeps the last 5; - flips
ERGO_TAG, starts, waits for the healthcheck and a registration handshake; - on failure: previous tag back; if the old version refuses the upgraded database ("Database requires update") the snapshot is restored too. Cause and snapshot path go into the ntfy message;
- on success: saves the new image's
default.yamlundertemplates/and, if it differs from the previous version's, writestemplates/diff-vA-vB.txtso new/renamed options are visible.
Releases whose notes announce compatibility breaks are held (one ntfy, not
daily) until you run ergoctl update update or set FORCE_UPDATE=1. Restarting
Ergo disconnects every user (there is no hot restart), so pick security if
that matters more than being current. Caddy is only updated by
ergoctl update caddy (or daily with CADDY_AUTOUPDATE=1); recreating it drops
web-client websockets. Update results reuse the ntfy config at
/etc/ssh-notify.conf when present.
Backups
ergoctl backup writes backups/ergo-backup-<ts>.tar.gz (0600) with
ircd.yaml, ircd.db, ergo.motd, the message history (the SQLite file, or a
pg_dump — a file copy of a live PostgreSQL data directory would not be a valid
backup) and a meta file (version, history backend, date). By default
it stops Ergo for a few seconds for a consistent copy (--live skips that).
Put an age public key in $STACK_DIR/age-recipients.txt (e.g. from
globals/age-pubkey.txt) and install age (apk add age, apt install age,
dnf install age — deploy.sh does not) and backups are encrypted with it; with
the recipients file present but age missing, ergoctl backup refuses rather
than writing the account and oper hashes out in the clear. TLS files are not
included — certsync regenerates them. ergoctl restore <file> stops Ergo, keeps the current config and database as
backups/{ircd.yaml,ircd.db}.pre-restore.<ts>, warns if the backup came from a
newer version (older Ergo cannot read a newer schema), restores, validates the
result before starting, and waits for health. Because the archive carries the
original host's credentials, restore re-points datastore.postgresql.password
at this host's secrets/postgres.pass and re-hashes this host's
secrets/admin.pass into the config — otherwise a rebuild would come up healthy
but leave you unable to /OPER. An encrypted backup needs the private key:
AGE_IDENTITY=/root/age.key ergoctl restore backups/ergo-backup-<ts>.tar.gz.age
``` Ergo's own `datastore.autoupgrade`
leaves `ircd/ircd.db.v<N>.<ts>.bak` files behind on schema upgrades; prune them
once you are happy with a release.
## Web client (optional)
The `wss://DOMAIN/webirc` endpoint is ready; Ergo only accepts browser
connections whose `Origin` is `https://DOMAIN` (`server.websockets.allowed-origins`).
To host [Gamja](https://codeberg.org/emersion/gamja) on the same origin, unpack a
release tarball into `caddy/www/gamja`, add
`{"server": {"url": "/webirc", "autojoin": "#lobby"}}` as `config.json`, mount
`./caddy/www:/www:ro` in the caddy service and drop a `handle { root * /www/gamja
file_server }` block into `caddy/etc/conf.d/` (see `00-readme.caddy`), then
`ergoctl caddy-restart`.
## Security model
- **Host loopback is Ergo's trust boundary.** Loopback peers are exempt from
bans and ip-limits, are treated as secure, and (because
`proxy-allowed-from: [localhost]` is what lets Caddy's `X-Forwarded-For`
through) may assert a client IP. Every local process and every other
host-network container can reach `127.0.0.1:6667`/`:8097`. This stack is for
a single-purpose container host without untrusted local users; deploy.sh
warns about other host-network containers.
- **Ergo runs unprivileged**: as the host's `ergo` system user, read-only root
filesystem, all capabilities dropped, `no-new-privileges`. `ircd/` (database,
config with the oper hash, TLS key) is `0700 ergo:ergo`; `secrets/`,
`backups/`, `caddy/data` are `0700 root`.
- **Root never follows a symlink into `ircd/`.** That directory is writable by
the container uid while the cert sync and every `ergoctl` config edit run as
root, so a plain `cp`/`install`/`>` there would let code execution inside Ergo
redirect a root write onto any file on the host. Every such write stages under
`$STACK_DIR` (0700 root) and lands with `mv` — `rename(2)` replaces a symlink
instead of following it — and root reads use `cp -P` or refuse outright.
- **Caddy runs as root** (it needs `NET_BIND_SERVICE` for 80/443) with every
other capability dropped, admin API off, HTTP/3 off.
- **Loopback plaintext is the control plane by design**: OPER over loopback is
not a downgrade (Ergo marks it secure), and it lets `ergoctl` work even when a
ban or throttle would lock out a remote client. `PLAINTEXT=1` puts real users'
credentials on the wire in clear — leave it at `0`.
- The admin password is sent to Ergo only over loopback and stored only in
`secrets/admin.pass`. `ergo genpasswd` hashes at bcrypt cost 4, so oper
passwords are always generated (24 random chars), never typed.
## Files
| File | Purpose |
|---|---|
| `docker-compose.yml` | caddy + ergo, both `network_mode: host`, hardened; IRC-level healthcheck. |
| `docker-compose.postgres.yml` | Optional PostgreSQL overlay for `HISTORY=postgres` (loopback-only, pinned major). |
| `Caddyfile` | ACME, `/webirc` websocket proxy, text landing page, `admin off`, no h3; imports `conf.d/*.caddy`. |
| `conf.d-readme.caddy` | Installed once as `caddy/etc/conf.d/00-readme.caddy` (operator drop-ins; Gamja example). |
| `ergo.motd` | MOTD template (`__NETWORK_NAME__`, `__DOMAIN__`, `__HISTORY_NOTE__`). |
| [`USER-GUIDE.md`](USER-GUIDE.md) | Quick-start for people new to IRC. Rendered to `docs/` on the host. |
| [`ADMIN-CHEATSHEET.md`](ADMIN-CHEATSHEET.md) | Moderator and admin quick reference. Rendered to `docs/` on the host. |
| `ergolib.sh` | Shared helpers: `.env`, compose, health/IRC probes, `--smoke` validator, oper edits, certsync, ntfy. |
| `update.sh` | Updater + certsync + Caddy update + scheduling. |
| `ergoctl` | Host admin CLI. |
| `.env.example` | Stack tunables. |
| `deploy.sh` / `build.sh` | Self-contained installer + archive embedder. |
| `cloud-init.yml` | Fresh-VM bootstrap (harden SSH, then deploy). |
On the host: `/srv/ergo/{ircd,caddy/{etc,data,config},secrets,backups,templates}`
plus `.state/` (notification de-duplication) and `.env.bak.<ts>` copies from each
update (last 5 kept); `/etc/ergo-update.conf` (where the jobs find the stack);
`/usr/local/bin/ergoctl`; `/var/log/ergo-update.log` (the **daily update run**
logs there, since busybox crond has nowhere else to put its output — cert-sync
failures instead surface through ntfy and as `certsync: LAST FAILURE` in
`ergoctl status`).
## Notes
- Only one host-networked Caddy fits on a box: don't co-locate this stack with
another Caddy/80/443 stack (deploy.sh checks the ports).
- DNS for `ERGO_DOMAIN` must resolve to the host and 80/443 be reachable before
deploy for the cert to issue; Ergo stays up on a self-signed cert meanwhile.
- Ergo's built-in registration is open by default, and **`allow-before-connect`
is also on**, so accounts can be created by a client that has not finished
connecting, throttled only globally (30 attempts per 10 minutes ≈ 4,300/day).
Each account is a durable row in `ircd.db`. For a private network set
`accounts.registration.enabled: false`, or keep registration but set
`allow-before-connect: false`, with `ergoctl edit`.
- The admin oper password is printed by `deploy.sh` only on the first run and
only to a terminal. Unattended runs (cloud-init) print the path instead, so the
credential does not end up in the provider's serial-console log; read it with
`ergoctl passwd show`.