Open source · Self-hosted · SaaS

Email infrastructure built for developers

Provision a working inbox address in seconds. Receive, thread, and reply to email over a clean REST API with real-time webhooks — no MX records, no MIME parsing, no undifferentiated plumbing.

Get started freeView on GitHub
quickstart.ts
// Create an inbox in seconds
const inbox = await fetch('/api/v1/emailInbox', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    name: 'Support',
    address: '[email protected]',
  }),
})

// Messages arrive via webhook
// { event: 'email.received', data: { ... } }
Inbox provisioned
< 1s
API parity with UI
100%
tenant from day one
Multi
Open source license
MIT

What you get

Everything the email stack should have been

Stop rebuilding the same undifferentiated plumbing. Programmable Inbox handles the full receive → thread → notify pipeline so you can focus on what your product actually does.

  • Instant inbox provisioning

    Create a fully functional email receiving address via API in one request. No DNS headaches, no MX record wrangling — just a working inbox.

  • Real-time webhooks

    Every inbound message fans out to your registered endpoints with HMAC-signed payloads, replay protection, and full delivery history.

  • API-first by design

    Every action in the UI has an exact REST equivalent. Build support tools, AI agents, or automated pipelines — the API is the product.

  • Smart threading

    Messages are threaded by In-Reply-To / References headers with a subject-match fallback, keeping conversations intact no matter the client.

  • Multi-tenant from day one

    Organizations, memberships, and resource scoping are built into the core. Safely serve multiple teams from a single deployment.

  • Full reply pipeline

    Send outbound replies with To/CC/BCC, HTML & plain text, and proper threading headers — all via a single authenticated API call.

Use cases

What you can build with it

From human-triaged support to fully autonomous AI agents, Programmable Inbox gives every use case the same reliable foundation.

  • Support

    Shared support inbox

    Wire your support@ address into Programmable Inbox. Agents triage threads in the built-in UI while your backend receives every event via webhook to sync tickets, SLAs, or CRM records automatically.

  • AI Agents

    AI agents that read and reply to mail

    Feed inbound email directly into an LLM pipeline. Your agent receives the parsed message, generates a reply, and fires POST /send — all without touching an SMTP server or IMAP library.

  • Automation

    Transactional reply handling

    Catch replies to automated outreach, parse intent, and route them to the right workflow. Proper threading means you never lose the original context, even across hundreds of conversations.

  • Ingest

    Email-to-webhook bridge

    Turn any email address into a programmable event source. Receive an email, emit a webhook, trigger a serverless function — classic email infrastructure modernized for the API era.

REST API

A clean API for every action

Every UI action maps to a documented REST endpoint. Build on top of the same primitives that power the inbox UI — no hidden capabilities.

POST /api/v1/emailInbox
Authorization: Bearer YOUR_API_KEY

{
  "name": "Support",
  "address": "[email protected]",
  "organizationId": "org_abc123"
}

// Response
{
  "data": {
    "id": "inbox_xyz789",
    "name": "Support",
    "address": "[email protected]",
    "createdAt": "2026-06-27T12:00:00Z"
  }
}

Why us

Built differently from the rest

Existing providers handle sending. Programmable Inbox is built around receiving — threading, triaging, and acting on inbound email at scale.

CapabilityProgrammable InboxPostmarkSendGridLoops
Receive email via webhook
Thread management & grouping
Built-in multi-tenant UI
100% API parity with UI
Self-hosted / open source
AI agent ready
Managed SaaS option

Open source forever

Your infra, your rules

We will always maintain a fully open source, self-hosted version of Programmable Inbox for the community. No lock-in. No paywalled features. No surprises.

Self-hosted

Deploy on your own infrastructure. Postgres, Next.js, and a Resend webhook is all you need. Full source code on GitHub under an MIT license — fork it, extend it, own it.

  • MIT licensed, forever
  • No feature gating
  • Bring your own domain
  • Community support on GitHub
Star on GitHub
Coming soon

Managed SaaS

Skip the ops. We'll handle uptime, backups, and scaling while you focus on your product. Every feature from the open source version, plus managed deliverability and priority support.

  • Zero-ops deployment
  • Managed uptime & backups
  • Priority support
  • Usage-based pricing
Join the waitlist

Community first. The self-hosted version will always be free, feature-complete, and actively maintained. That's a promise, not a pricing tier.

Pricing

Simple, honest pricing

Open source is free forever. SaaS pricing will be usage-based with a generous free tier.

Open Source

Freeforever

Self-host on your own infrastructure. Everything you need, nothing you don't.

  • Unlimited inboxes
  • Unlimited messages
  • Full REST API
  • Webhook fan-out
  • Multi-tenant orgs
  • MIT license
  • Community support
View on GitHub
Early access

SaaS

Coming soonusage-based pricing

We run it. You build with it. All the power, none of the ops.

  • Everything in Open Source
  • Zero-ops managed hosting
  • Managed deliverability
  • Automatic backups
  • Uptime SLA
  • Priority support
  • Usage-based pricing
Join waitlist

Start building in seconds

Self-host for free with the open source version, or join the waitlist for our managed SaaS. Either way, you own your data and your stack.

Get started freeSelf-host on GitHub

No credit card required · MIT license · Community supported