Your app or Worker
Send transactional mail using the API.
YOUR ACCOUNT, ALL THE WAY DOWN.
How the pieces fit.
In your account.
Box Ox is the app and API. Cloudflare supplies the runtime, mail transport, storage, and owner sign-in.
HOW IT WORKS
A simple email workflow.
In your own account.
From your application to the inbox, with stored message history and signed events along the way.
Your Box Ox
Runs in your Cloudflare account.
Inbox + delivery
Store mail and follow each message.
Events + webhooks
React to delivery and inbound events.
INSTALLATION
From install to inbox.
You choose the account, domains, and permissions.
1. Deploy your installation
Download the project or give the guide to your agent. The deployment helper provisions the declared resources and applies migrations. The app can use your free workers.dev address or an optional custom hostname.
2. Protect owner access
Configure Cloudflare Access for your chosen hostname and owner identity. Owner APIs fail closed before Access is configured. Credential-protected developer and agent endpoints use the exact public protocol exceptions described in the setup guide.
3. Connect a mail domain
Your email domain must be on Cloudflare DNS. Choose sending only to keep existing receiving records, or preview and confirm receiving changes. Receiving uses Email Routing to reach your Worker; stored mail goes to R2 and metadata to D1.
4. Connect your application or agent
Applications send through a domain-scoped key. Delivery events reach Cloudflare Queues and update Box Ox logs and signed webhooks. Agents use your Worker’s MCP or agent API, with grants you can revoke.
What runs where?
- Cloudflare: the app, API, remote MCP, workflows, mail storage, database, and mail transport.
- Your computer or CI: the CLI, deployment tools, and local development.
- Boxox.dev: this public website, downloads, and documentation.
Start building with Box Ox today.
Your app’s mail. Its replies. Your Cloudflare.
Get your own Box OxSelf-hosted · Free software · Cloudflare bills your usage, and R2 needs a payment method on file