The "behind an existing Caddy" section assumed the DNS plugin was being set up from scratch. The realistic case is a box whose Caddy already does Cloudflare DNS-01 for another domain, so it now covers that: set acme_dns once globally and every site inherits it, or scope a token per zone with a snippet. Leads with the failure that will actually happen -- a Cloudflare token is scoped to named zones, so the existing one grants DNS:Edit on the domain it was made for and nothing else, and the new site fails its challenge on a permissions error whose text does not say so. Also spells out that *.test.rosterchief.app does NOT match test.rosterchief.app: a wildcard covers exactly one label, so leaving the bare host off the site line gives the club subdomains a certificate and the control panel none. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Deploying RosterChief
One server today, several later, with no code changes in between — only environment variables. This document is the runbook and, more usefully, the list of things that are specific to this app and will bite you if you treat it as a generic Django deploy.
The five things that make this deployment unusual
1. You need a wildcard TLS certificate, and that forces DNS-01.
Tenancy is subdomain-based (ajax.rosterchief.app), so the certificate must cover
*.rosterchief.app. Let's Encrypt will not issue a wildcard over HTTP-01 — only over
DNS-01, which means the TLS terminator needs API access to your DNS zone. That is why
deploy/caddy/Dockerfile builds Caddy with a DNS provider plugin, and why
CLOUDFLARE_API_TOKEN is a required variable rather than a nicety. Swap the plugin
(caddy-dns/route53, caddy-dns/digitalocean, …) if your DNS lives elsewhere.
DNS needs two records, both pointing at the server:
A rosterchief.app -> <server ip>
A *.rosterchief.app -> <server ip>
2. Redis is not optional, even on one server.
waffle caches each feature flag's targeting in the Django cache, and LocMemCache is
private to a single process. Under several gunicorn workers, toggling a feature in the
control panel flushes one worker's cache while the others keep serving the stale flag —
a feature that "sometimes doesn't turn on". A shared cache is the fix.
3. SECURE_PROXY_SSL_HEADER must be set, and Caddy must send the header.
Caddy terminates TLS, so without it Django believes every request is plain HTTP:
request.is_secure() goes false, WebAuthn disagrees with the browser about the origin, and
SECURE_SSL_REDIRECT becomes a redirect loop. Both halves are already wired (settings +
header_up X-Forwarded-Proto); don't remove either.
4. Uploads must move to object storage before the second app server.
Club logos go to MEDIA_ROOT on local disk. On one box that is fine. On two, a logo
uploaded to node A is a 404 on node B. Setting AWS_STORAGE_BUCKET_NAME switches the
default storage to S3 — do it before you scale, not during.
5. PDF invoices need native libraries. WeasyPrint binds to pango/cairo. The image installs them; a bare-metal deploy would need them too, and a Mac needs Homebrew. This is the main reason to run the container even in development if you touch invoicing.
First deploy
# 1. Configure
cp .env.compose.example .env # read by docker compose
cp .env.production.example .env.production # read by Django
python -c "import secrets; print(secrets.token_urlsafe(64))" # -> DJANGO_SECRET_KEY
# 2. Build and start
docker compose build
docker compose up -d db redis
docker compose run --rm web python manage.py migrate
docker compose run --rm web python manage.py createsuperuser
docker compose up -d
# 3. Verify
curl -fsS https://rosterchief.app/healthz # {"status": "ok", ...}
docker compose run --rm web python manage.py check --deploy
check --deploy is what catches an env file that forgot the HTTPS flags: they default to
off in code, because defaulting them to not DEBUG would redirect every test request to
https and break the suite anywhere DEBUG is unset.
The first docker compose up will take a minute or two: Caddy is provisioning the wildcard
certificate over DNS-01, and DNS propagation is not instant. Watch it with
docker compose logs -f caddy.
Migrations
Deliberately not run by the container's entrypoint. With more than one web container they would race, and a starting gunicorn worker is a bad place to discover a failed migration. Run them once, explicitly, as part of the deploy:
docker compose build
docker compose run --rm web python manage.py migrate
docker compose up -d --no-deps web
Scheduled jobs
Two commands need to run on a schedule. Put them on the host, not in a container, and on exactly one node when you have several — three nodes archiving the same club is three emails to the same club.
# Bill: archive clubs unpaid past their grace period.
# Run it WITHOUT --commit for the first week and read the output. The flag exists because
# this switches off paying customers: a bad clock or a bad cron should cost you an email,
# not a morning of angry clubs.
0 6 * * * cd /srv/rosterchief && docker compose run --rm web python manage.py archive_overdue_clubs --commit
# Events: extend recurring series so the calendar never runs dry.
0 3 * * * cd /srv/rosterchief && docker compose run --rm web python manage.py extend_event_series
Maintenance mode
Control panel → Features → Maintenance mode. While it is on:
- every club subdomain serves a 503 maintenance page, in that club's own colours;
- the control panel and the sign-in screens stay open, because closing them would leave you with no way to turn it back off;
/healthzkeeps answering on every host, or the load balancer would take the node out of rotation and the control panel with it;- the scheduled jobs stand down —
archive_overdue_clubs,extend_event_seriesandimport_members_csvrefuse to run.
migrate and collectstatic are deliberately not blocked. Maintenance is usually
declared in order to run them, and a guard that stopped them would mean turning the mode
off to do the work you turned it on for.
The scheduled jobs exit non-zero while the platform is closed, so cron will mail you.
That is intended: a job that silently skips itself is how a month of billing goes missing. If
you genuinely mean to run one during a window, pass --ignore-maintenance.
So a migration-heavy deploy looks like:
# 1. Close the platform in the control panel (or from a shell):
docker compose run --rm web python manage.py shell -c \
"from features.models import Maintenance; Maintenance.start(message='Upgrading. Back by 21:00.')"
# 2. Do the work — migrate is not blocked.
docker compose build
docker compose run --rm web python manage.py migrate
docker compose up -d --no-deps web
# 3. Reopen from the control panel.
The state lives in Redis as well as the database, so it takes effect on every worker and every server at once — a per-process cache would leave some workers still serving clubs.
Behind an existing Caddy (dev / test server)
If the box already runs Caddy on :80 and :443 — a test server sharing a host with other sites — do not run ours: two Caddies cannot both hold port 80. Run the app only, publish it on the loopback, and add a site block to the Caddy that is already there.
docker compose -f compose.behind-proxy.yaml up -d # web + db + redis, no caddy
web publishes on 127.0.0.1:8001 (override with WEB_PORT). Loopback, not 0.0.0.0 —
bound to all interfaces, a test instance is reachable at http://<server-ip>:8001 with no
TLS, bypassing the proxy and every security header with it.
Then add a site block to the host's Caddyfile. Caddy serves any number of domains on the same ports — TLS is chosen per connection by SNI — so a second (or tenth) site is just another block.
If that Caddy already does Cloudflare DNS-01
Which is the usual case: the box has a domain on Cloudflare and Caddy already has the DNS
plugin. Then set the challenge once, globally, and every site inherits it — no tls
block per site, and wildcards simply work:
{
email you@example.com
# Applies DNS-01 to every site below.
acme_dns cloudflare {env.CLOUDFLARE_API_TOKEN}
}
# --- whatever the box already serves --------------------------------------
existing-thing.example.com {
reverse_proxy 127.0.0.1:3000
}
# --- RosterChief test instance --------------------------------------------
# The bare host AND the wildcard, on one certificate.
test.rosterchief.app, *.test.rosterchief.app {
encode zstd gzip
reverse_proxy 127.0.0.1:8001 {
header_up X-Forwarded-Proto {scheme}
header_up X-Real-IP {remote_host}
}
}
If the two domains need different tokens
Different Cloudflare accounts, or tokens scoped per zone. Drop acme_dns and give each site
its own tls; a snippet keeps it short:
{
email you@example.com
}
(cf) {
tls {
dns cloudflare {args[0]}
}
}
existing-thing.example.com {
import cf {env.CF_TOKEN_EXAMPLE}
reverse_proxy 127.0.0.1:3000
}
test.rosterchief.app, *.test.rosterchief.app {
import cf {env.CF_TOKEN_ROSTERCHIEF}
reverse_proxy 127.0.0.1:8001 {
header_up X-Forwarded-Proto {scheme}
}
}
What actually goes wrong
-
The token must cover the new zone. A Cloudflare token is scoped to named zones, and an existing one almost certainly grants
Zone:DNS:Editon the domain it was made for and nothing else. The new site then fails its DNS-01 challenge on a permissions error whose text does not say so. Widen the token, or mint a second one and use the snippet form. -
Both hostnames must be listed.
*.test.rosterchief.appdoes not matchtest.rosterchief.app— a wildcard covers exactly one label. Leave the bare host out and the club subdomains have a certificate while the control panel does not. Hence the comma. (Wildcards are also only one level deep:ajax.test.…yes,a.b.test.…no.) -
Caddy must have the DNS plugin. Stock
caddycannot answer a DNS-01 challenge at all.caddy add-package github.com/caddy-dns/cloudflare, or run a Caddy built likedeploy/caddy/Dockerfile. (If DNS-01 already works on the box, you have it.) -
The token must be in Caddy's environment, not your shell's —
{env.…}reads the process it runs in:# /etc/systemd/system/caddy.service.d/override.conf [Service] EnvironmentFile=/etc/caddy/caddy.env # CLOUDFLARE_API_TOKEN=...Then
systemctl daemon-reload && systemctl restart caddy. -
header_up X-Forwarded-Protois not optional, exactly as in the bundled Caddyfile: without it Django believes the request behind the proxy is plain HTTP. -
Give the test instance its own subdomain tree and set
ROSTERCHIEF_BASE_DOMAIN=test.rosterchief.app. That variable drives tenant resolution, the shared session cookie and the WebAuthn RP ID — point it at the production domain and test passkeys start colliding with real ones.
Applying and checking it
caddy validate --config /etc/caddy/Caddyfile # syntax and modules
systemctl reload caddy # zero downtime; existing certs untouched
journalctl -u caddy -f # watch the DNS-01 challenge
curl -I https://test.rosterchief.app/healthz
curl -I https://any-club-slug.test.rosterchief.app/ # proves the WILDCARD, not just the host
Reloading provisions only what is new, so the existing site's certificate is not reissued. Allow 30–60s for the DNS record to propagate before the challenge completes.
DNS needs both records, pointing at the test box:
A test.rosterchief.app -> <server ip>
A *.test.rosterchief.app -> <server ip>
The compose project is named rosterchief-test, so its containers and volumes never collide
with a production stack on the same host.
Automated backups
deploy/backup.sh dumps the database, tars the uploads while they are still on local disk,
prunes anything older than KEEP_DAYS, and — if you set BACKUP_REMOTE — copies the lot off
the box with rclone.
deploy/backup.sh /var/backups/rosterchief
It writes to a .part file and only moves it into place once gzip -t says the archive is
readable and non-empty. A truncated dump that looks like a backup is the failure mode worth
engineering against, because you only discover it on the day you need it.
Schedule it as root on the host (single server; on several, run it on the database node):
# Nightly at 02:30, before the billing and event jobs.
30 2 * * * cd /srv/rosterchief && BACKUP_REMOTE=b2:rosterchief-backups KEEP_DAYS=14 deploy/backup.sh /var/backups/rosterchief
# Weekly restore rehearsal into a throwaway database. This is the only line here that proves
# the others work.
0 4 * * 0 cd /srv/rosterchief && deploy/restore-check.sh
Cron mails you on non-zero exit, and the script uses set -Eeuo pipefail so it does exit
non-zero. A backup script that fails quietly is worse than none, because you will believe you
have backups.
Offsite matters more than frequency. A dump sitting on the same disk as the database
survives a bad migration but not the server. BACKUP_REMOTE takes any rclone remote (S3,
Backblaze, a second box).
Once uploads move to S3 (AWS_STORAGE_BUCKET_NAME), the script skips the media tarball:
the bucket's own versioning is the backup. Turn versioning on when you create it.
Restoring
gunzip -c /var/backups/rosterchief/db-2026-07-14-0230.sql.gz \
| docker compose exec -T db psql -U rosterchief rosterchief
The dump is taken with --clean --if-exists, so it drops and recreates rather than colliding
with what is there. Rehearse it once, now, against a scratch database — not the first time you
need it.
Backups (manual)
Two things carry state: Postgres and the uploads.
# Database
docker compose exec -T db pg_dump -U rosterchief rosterchief | gzip > rosterchief-$(date +%F).sql.gz
# Uploads — until they are on S3, in which case the bucket's own versioning is the backup.
docker compose cp web:/app/media ./media-backup
Restore is gunzip -c dump.sql.gz | docker compose exec -T db psql -U rosterchief rosterchief.
Test it once, now, rather than the first time you need it.
Going multi-server
Nothing in the code changes. What changes is where the services live:
| one server | several | |
|---|---|---|
| Postgres | db container |
DJANGO_DATABASE_URL → your central Postgres |
| Cache / flags | redis container |
managed Redis (or your existing one) |
| Uploads | local disk | S3 bucket (AWS_STORAGE_BUCKET_NAME) |
| Static files | WhiteNoise, in the image | unchanged — that is why WhiteNoise is there |
| Cron | host crontab | one node only |
| TLS | Caddy on the box | load balancer, or Caddy on each node |
Drop db and redis from compose.yaml, point the URLs at the central services, and run
web on as many nodes as you like behind a load balancer pointed at /healthz.
The health check tests the database and a cache round trip, not just that the process is listening — a node that cannot reach Postgres, or whose cache silently swallows writes, is not healthy, and a load balancer must not keep feeding it traffic.
Rollback
Images are the unit of rollback. Tag on build, keep the last few, and:
docker compose up -d --no-deps web # with the previous image tag
Migrations are the exception: they don't roll back with the image. Prefer additive migrations (add a column, deploy, backfill, then stop writing the old one) so that yesterday's image still runs against today's schema.