See .env.example in the main Mantis repo for the canonical, commented list. These are the variables operators usually need to understand.

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Required

  • DATABASE_URL — Postgres connection string. Used directly when you run Mantis from source (pnpm dev, pnpm db:migrate) — point it at your own Postgres. The Docker Compose deploy ignores this value and derives its own from POSTGRES_PASSWORD (connecting to host postgres, not localhost), so a localhost value kept here for run-from-source does no harm.
  • POSTGRES_PASSWORD — password for the Docker Compose Postgres service, and the single source of truth from which Compose builds the app’s DATABASE_URL. It ships empty in .env.example and has no insecure default: both Compose services abort on boot if it is unset or empty. Generate it (together with the pepper below) by running ./scripts/setup.sh — a bare cp .env.example .env is not enough to start the stack. Not needed when running from source against your own Postgres.
  • MANTIS_API_KEY_PEPPER — server-side secret used as the HMAC key when hashing API keys at rest. Generate with openssl rand -base64 32. A leaked database alone is useless to an attacker without this value too. Do not rotate after the first key is minted — rotating invalidates every existing API key used by the CLI or API clients. If you must rotate, plan to re-mint and re-distribute every API key on the same maintenance window. Upgrading from a pre-pepper deployment? Set the pepper once and existing API keys keep working — the verifier accepts the old pre-pepper SHA-256 hashes too, and opportunistically re-hashes each row to the peppered form on next use. After a few weeks of normal traffic the legacy rows drain to zero.
  • MANTIS_SECRET_KEY (optional) — envelope-encryption key for operator secrets stored in the database: per-destination webhook HMAC signing secrets, the Apple Wallet auth secret, and the .p12 certificate passphrase. When set, those columns are sealed at rest with AES-256-GCM (an encv1: envelope) so a database-only leak (backup, read replica) yields no usable secrets — the same trust model as the pepper above. Generate with openssl rand -base64 32 (a 64-character hex string also works; it must decode to exactly 32 bytes). Leave it unset to keep plaintext-at-rest behavior. The feature is backward compatible: existing plaintext rows are read transparently, and once the key is set, new writes are encrypted while legacy rows migrate to ciphertext the next time a signing secret is rotated. (A legacy DB wallet config can’t be re-saved — wallet config is env-var driven now — so clear it from /settings/wallet instead of leaving its plaintext secrets in the database.) Don’t rotate this key without re-saving those secrets, and don’t remove it once rows are encrypted — reads of sealed values will then fail.

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URLs

  • PUBLIC_BASE_URL — public origin used when Mantis generates trigger, status, and Wallet callback URLs. Defaults to http://localhost:3000.
  • MANTIS_PUBLIC_PATH — trigger path prefix, default /c. Changing this changes generated URLs and the public-only host allowlist; the app rewrites <prefix>/<id> onto its trigger handler itself, so no reverse-proxy rewrite is needed (server ≥ 0.2.0 — earlier releases needed one). Responses under a custom prefix also carry the dashboard’s security headers (X-Frame-Options: DENY, CSP), which only matters if you embed an html response kind in an iframe.

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Boot and runtime

  • BOOTSTRAP_API_KEY — pre-seed the first admin API key. If unset and no API keys exist, Mantis mints one and prints it on first boot.
  • AUTO_MIGRATE=1 — apply pending migrations on app boot. Useful for long-running container deploys; avoid for Vercel/serverless.
  • RUN_NOTIFY_WORKER=0|1 — notification worker switch. It runs by default outside Vercel; set 0 when using cron mode instead.
  • CRON_SECRET — required to enable GET/POST /api/cron/notifications. The endpoint fails closed with 401 when unset.
  • LOG_LEVEL — trace|debug|info|warn|error, default info.

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Notification destinations

  • SMTP_URL — enables email notification destinations. Example: smtp://user:pass@host:587.
  • SMTP_FROM — email sender, default Mantis <mantis@localhost>.
  • ALLOW_PRIVATE_WEBHOOKS=1 — allow webhook/Slack/Discord/Teams targets that resolve to private, loopback, link-local, or cloud-metadata IPs. Default is blocked as an SSRF guard.

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Global notification destinations

Beyond the per-key destinations managed with mantis destinations, an admin can set instance-wide destinations from the dashboard at /settings/notifications. Every key’s hits fan out to its own destinations plus every global one, so you can set a Slack or webhook once and have every key you mint — including bulk-created ones — alert you without further setup. A destination listed both globally and on a key fires once (the key’s own row wins, keeping its signing secret and activation history). There is no environment variable or CLI subcommand for the global set; it lives only in the admin dashboard.

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Proxy and public-only hosts

  • TRUST_PROXY_HEADERS=1 — trust cf-connecting-ip, x-vercel-forwarded-for, x-real-ip, and x-forwarded-for for forensic IP logging. Set only behind a proxy that strips and re-injects those headers. Auto-enabled on Vercel and in non-production; set TRUST_PROXY_HEADERS=0 to force it off even there. In production with no trusted proxy (the default), client IPs are recorded as null rather than spoofable values, and Mantis logs a one-time startup warning.
  • TRUSTED_IP_HEADER — pin client-IP extraction to a single header (matched case-insensitively), e.g. x-real-ip. By default Mantis tries cf-connecting-ip, x-vercel-forwarded-for, x-real-ip, then x-forwarded-for and takes the first present; behind a non-Cloudflare proxy (nginx, Caddy, Traefik) that sets only x-real-ip and doesn’t strip an inbound cf-connecting-ip, an attacker could forge cf-connecting-ip and have it trusted. Pin this to the one header your proxy authoritatively writes so all others are ignored. Only takes effect when TRUST_PROXY_HEADERS is on.
  • TRUST_PROXY_HOPS — number of trusted reverse-proxy hops in front of Mantis, default 1 (clamped to 1–16). Only affects x-forwarded-for parsing: the client IP is taken this many entries from the right of the chain (your nearest proxy appends the real peer on the right), so a client can’t forge it past your proxy. Raise it only if you stack multiple trusted proxies; it has no effect on single-value headers like cf-connecting-ip or x-real-ip.
  • FORCE_SECURE_COOKIES — override the Secure flag on the dashboard session cookie. 1 forces it on, 0 forces it off; unset derives it from the request scheme (X-Forwarded-Proto, or the RFC 7239 Forwarded header’s leftmost hop). Set 1 behind a proxy or tunnel that terminates real TLS but sets neither scheme header — otherwise the session cookie travels un-Secure over genuine HTTPS. Leave it unset for the proxies Mantis documents (Cloudflare, cloudflared, Tailscale, nginx), which all set a scheme header. Don’t force it on over plain HTTP: the browser would then never send the cookie back and login would break.
  • PUBLIC_ONLY_HOSTS — comma/space-separated hostnames that should expose only public routes: trigger URLs, status URLs, and Wallet callbacks.
  • DASHBOARD_HOSTS — hostnames allowed to serve the dashboard and management API. When PUBLIC_ONLY_HOSTS is set, unknown hosts fail closed to public-only unless explicitly listed here.
  • PUBLIC_ONLY_ALLOW_HEALTH=1 — allow /api/health on public-only hosts.
  • PUBLIC_ONLY_ALLOW_INBOX=1 — allow /inbox and /api/inbox on public-only hosts. Use only for deliberate dev boxes.

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Hit storage

  • MANTIS_DUPLICATE_LOG_LIMIT — duplicate hit rows to store per dedupe window after the first hit. Default 10; 0 stores only the first hit in the window.
  • MANTIS_MAX_STORED_REQUEST_FIELD_CHARS — cap for stored user-agent, referer, and individual header values. Default 16384.
  • MANTIS_MAX_STORED_HEADER_SNAPSHOT_CHARS — cap for the total stored header snapshot. Default 65536.

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Retention

Unset retention variables mean retain forever. The notify worker sweeps hourly; cron mode runs the same sweep through /api/cron/notifications.
  • MANTIS_HIT_RETENTION_DAYS — delete hits older than N days; notifications cascade.
  • MANTIS_NOTIFICATION_RETENTION_DAYS — delete settled notifications older than N days.
  • MANTIS_AUDIT_RETENTION_DAYS — delete append-only audit events older than N days.
  • MANTIS_SESSION_RETENTION_DAYS — delete revoked or expired dashboard sessions older than N days. Active sessions are not affected.

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Dev inbox

  • ENABLE_DEV_INBOX=1 — enable the in-memory /inbox webhook capture and /api/inbox JSON API. The /inbox/<slug> capture endpoint is unauthenticated by design (so it can receive webhooks), but reading or clearing the buffer (GET/DELETE /api/inbox) requires an API key or dashboard session. Leave off in production.

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Docker and tunnels

  • MANTIS_BIND_HOST — compose host bind address, default 127.0.0.1.
  • MANTIS_HOST_PORT — compose host port, default 3000.
  • TS_AUTHKEY, TS_HOSTNAME, TS_PRIVATE_HOSTNAME, TS_PUBLIC_HOSTNAME, TS_EXTRA_ARGS — Tailscale sidecar configuration.
  • CLOUDFLARE_TUNNEL_TOKEN — Cloudflare Tunnel sidecar token.

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Apple Wallet

Apple Wallet is configured with env vars — mount the certificate and secrets with your deploy (e.g. docker secrets), not through the app. The admin page at /settings/wallet is read-only: it shows whether Wallet is configured and from which source. Earlier versions had a dashboard upload form that stored the config in the database; a leftover DB config still works (env vars take precedence) but can only be cleared from that page, not re-saved. Required to enable .pkpass generation:
  • APPLE_PASS_CERT_PATH — Pass Type ID .p12 certificate.
  • APPLE_PASS_CERT_PASS — password for the .p12.
  • APPLE_PASS_TEAM_ID — 10-character Apple Team ID.
  • APPLE_PASS_TYPE_ID — Pass Type ID, for example pass.com.example.mantis.
  • APPLE_PASS_AUTH_SECRET — random secret used to derive per-pass Wallet auth tokens.
Optional:
  • APPLE_PASS_WWDR_PATH — Apple WWDR intermediate PEM override. Mantis also bundles a WWDR cert.
  • APPLE_PASS_ICON_PATH — custom 58x58 PNG icon.
  • APPLE_PASS_LOGO_PATH — custom 160x50 PNG logo.
  • APPLE_PASS_ORG_NAME — pass organization name, default Mantis.
  • APPLE_PASS_APNS_KEY_PATH — APNs .p8 auth key for pass-update pushes.
  • APPLE_PASS_APNS_KEY_ID — APNs key ID.
  • APPLE_PASS_APNS_SANDBOX=1 — use APNs sandbox instead of production.