Deploy and Host JMAP Webmail on Railway

A modern webmail for any JMAP server. Stalwart is a superb mail server that ships without a webmail UI; Fastmail, Cyrus and Apache James speak JMAP too. This template is a fast, offline-capable JMAP mail client you point at your server — one container, two variables, done.

About Hosting JMAP Webmail

A single SvelteKit (Node) service with a volume at /app/.data for its SQLite store: sessions, rate limits, settings and push subscriptions. Set PUBLIC_JMAP_SERVER_URL to your Stalwart server's base URL (e.g. https://mail.example.com) — everything else has working defaults, and SESSION_SECRET is auto-generated. Your users sign in with their mailbox email + password (app passwords and password$totp TOTP suffixes work); credentials are AES-256-GCM-sealed in a server-side SQLite store, the browser cookie only ever holds an opaque session id, and all JMAP traffic is proxied same-origin. The client is Zaur Mail 2: mail, contacts, calendar and server-side filter rules in one app, with drafts and an outbox that keep working offline, live updates over JMAP push, and phone and tablet layouts. It installs as a PWA. There's a Stalwart template on Railway too — deploy both for a complete self-hosted mail stack.

Common Use Cases

Give a self-hosted Stalwart server the webmail UI it doesn't ship with
Small teams and families running their own mail who want a fast, modern client with contacts, calendars and vacation responses
A browser and phone client for any JMAP account, with new-mail push notifications once you add VAPID keys

Dependencies for JMAP Webmail Hosting

A JMAP mail server — Stalwart, Fastmail, Cyrus or Apache James. This is a client, it does not run a mail server
Everything else is bundled: one service, one volume, no database to manage

Deployment Dependencies

Zaur Mail 2 README
Source on GitHub (apps/mail2)
Stalwart mail server — pair with the Stalwart template

Implementation Details

Recommended: Stalwart OAuth. With OAuth the server stores revocable tokens instead of the password:

In Stalwart, register an OAuth client — redirect URI https:///api/auth/oauth/callback, PKCE S256.
Set STALWART_OAUTH_ENABLED=true, STALWART_OAUTH_ISSUER_URL (usually your JMAP URL) and STALWART_OAUTH_CLIENT_ID.
Password sign-in disables itself automatically.

Notes:

Push notifications: generate keys with npx web-push generate-vapid-keys and set VAPID_PUBLIC_KEY, VAPID_PRIVATE_KEY and VAPID_SUBJECT. Without them the app still updates live while open; it just can't notify when closed.
The interface is neutral "Webmail" by default; rebrand it with PUBLIC_APP_NAME, PUBLIC_BRAND_NAME, PUBLIC_MAIL_DOMAIN and PUBLIC_APP_ICON.
Calendars, quotas and vacation responses are feature-probed, so the client degrades gracefully with your server configuration.
Other JMAP servers: set JMAP_AUTH=basic for Cyrus or Apache James, or JMAP_AUTH=token for Fastmail (users paste an API token as the password, PUBLIC_JMAP_SERVER_URL=https://api.fastmail.com/jmap/session). Calendar, contacts, files, filters and vacation replies only appear when the server offers them.
Signup and password-reset flows stay hidden unless you wire the optional register service — manage accounts in Stalwart directly.
PORT=3000, HOST=:: (dual-stack for Railway networking) and RAILWAY_RUN_UID=0 (volume write access) are pre-configured — leave them as they are.

Why Deploy JMAP Webmail on Railway?

Railway is a singular platform to deploy your infrastructure stack. Railway will host your infrastructure so you don't have to deal with configuration, while allowing you to vertically and horizontally scale it.

By deploying JMAP Webmail on Railway, you are one step closer to supporting a complete full-stack application with minimal burden. Host your servers, databases, AI agents, and more on Railway.