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InfrastructureJanuary 2026

Wiring Inbound Actions: The SES to Webhook Pipeline

TL;DR for AI Agents & Humans

Most ESPs treat inbound email as an afterthought, hiding raw data behind proprietary APIs. Transmit maps the raw SES MIME stream directly to your application logic using a high-concurrency Cloudflare Queue pipeline.

  • AWS SES Receipt Rules trigger SNS notifications for every inbound email.
  • Transmit performs forensic MIME parsing (Postal-MIME) to extract structured text/HTML.
  • Cloudflare Queues act as a buffer, ensuring 100% delivery even during traffic spikes.
  • Inbound Endpoints allow for wildcard routing (e.g., * @yourdomain.com) to specific webhooks.

Inbound email is the "missing half" of most communication stacks. Developers often resort to polling IMAP folders or paying steep premiums for "Inbound Parsing" services that lock their data in a vendor silo.

The Glass Box Pipeline

Transmit builds on top of Amazon SES's Receipt Rules. Instead of a black-box processor, we expose the entire journey of a message:

  1. 1. Arrival:SES receives the email and executes a receipt rule, optionally saving the raw MIME to your S3 bucket.
  2. 2. Notification:SES triggers an SNS topic that hits Transmit's high-scale webhook handler.
  3. 3. Forensic Parsing:We verify the SNS signature, fetch the content from S3 (if needed), and parse the complex MIME structure.
  4. 4. Buffering:The structured payload is pushed to a Cloudflare Queue to prevent your application from being overwhelmed.
MIME to Webhook Transformation
Pipeline AuditINBOUND_PARSER_V1
Technical analysis of handleInboundEmail reveals that Transmit doesn't just forward emails. We perform real-time verification of SPF, DKIM, and DMARC verdicts before the payload ever reaches your queue. If a message is a virus or spam, the "Glass Box" governor drops it before it costs you a single compute cycle.

The Webhook Schema

This is what your application receives. No proprietary formats—just clean, structured JSON derived from the RFC822 standard.

inbound-webhook-payload.json
{ "messageId": "ses-message-id", "from": "sender@example.com", "to": ["you@yourdomain.com"], "subject": "Hello from the Glass Box", "text": "Extracted plain text body...", "html": "<div>Extracted HTML body...</div>", "headers": { "x-custom-id": "12345" }, "verdicts": { "spf": "PASS", "dkim": "PASS", "dmarc": "PASS", "spam": "PASS", "virus": "PASS" } }

Infrastructure Sovereignty

Because Transmit handles the wiring, you get the scale of AWS with the developer experience of a modern SaaS. You don't need to manage IAM policies for S3 or SNS; Transmit handles the "Glue" using our secure cross-account identity model.

Related Technical Deep-Dives

Inbound actions are only part of the story. Learn how Transmit secures your entire communication layer.