Postal is a complete, self-hosted mail server — the open-source alternative to Sendgrid, Mailgun or Postmark, ready to run on your own infrastructure.

This is a fork maintained by Startup Pack that extends Postal with a full provisioning API, multi-tenant SCIM, and enterprise SSO features not available in the upstream project.

⚠️ Still running in dev mode. The Startup Pack deployment currently runs in development mode (Rails development — RAILS_ENV is not set, hence the "dev" badge in the UI footer). Before real production use, switch it to production: set RAILS_ENV=production (and NODE_ENV=production) on the web/smtp/worker processes, confirm secret_key_base and precompiled assets. Until then expect verbose logs, no asset caching and dev-mode behaviour.

• Documentation
• What this fork adds
• API v2 reference
• SCIM v2
• SSO / OIDC
• Upstream project — official Postal (Krystal Hosting Ltd, not affiliated)

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What this fork adds

🚧 Major rewrite in progress. The provisioning API, SCIM and SSO layers described below are being redesigned as a proper Rails engine with a stable public contract. The current implementation works but is considered alpha — interfaces may change without notice until the rewrite ships.

Feature	Description
Admin REST API v2	Provision orgs, servers, domains, credentials and users over HTTP — no Rails console needed
Per-user API access	JWT (RS256) via any OIDC provider; role-enforced per endpoint
Multi-user orgs	admin, member, readonly roles per org, managed via API or SCIM
SCIM v2 per-tenant	/scim/v2/tenants/:org/Users — user lifecycle and org params managed by your IdP
Multi-provider OIDC	Multiple IdPs (Keycloak, Entra, Google…) with one login button each
Back-Channel Logout	IdP-initiated session invalidation via signed logout_token
RP-Initiated Logout	Postal redirects to the IdP end_session_endpoint on sign-out
SSO auto-org	New SSO users get a default org created from their username
Auto SMTP server	Every new org gets a Live server + credential automatically

This fork is not affiliated with the official postalserver/postal project.

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Documentation

Full API reference, configuration examples, SCIM and OIDC guides:

startuppack.github.io/postal