Build and send an email broadcast
Broadcasts are one time marketing emails. You choose an audience, build the message visually, review the eligible recipient count, then explicitly schedule or start delivery.
Lists and segments
Subscriber lists
A list contains people who explicitly subscribed. Use a list for newsletters, announcements, and other opt in communication.
Dynamic segments
A segment is a saved set of rules over eligible CRM contacts. Membership can change as contact data and funnel activity change.
The broadcast workflow
Recipients
Select one subscriber list or one dynamic segment. The audience equation shows total contacts, exclusions, and the final eligible count before you continue.
Design
Set the subject, which also names the broadcast everywhere in Mirin. Click any content block to edit it directly. The desktop and mobile previews use the same content that will be saved. Editing after proofing requires a new proof.
Proof
Send the current message to up to five test addresses. At least one proof must succeed before delivery becomes available.
Deliver
Choose send now or schedule later, review required checks and recommendations, confirm the final audience, then explicitly start delivery.
Mirin keeps the current workflow step in the broadcast URL. If you refresh while designing, proofing, or preparing delivery, the composer returns to that same step.
Designing the message
Click a block in the rail to add it, or drag it to the position you want. Select a block on the canvas to edit its content, alignment, link, or image details. The move controls provide a precise keyboard friendly way to reorder the same blocks.
Write with Codex starts from one brief. Codex infers the email type and tone instead of asking you to classify the message. A blank canvas creates a new email. A canvas with meaningful content defaults to improving the current subject, live text, and editable blocks. You can choose Start over when you intentionally want to replace it. Local development uses the authenticated Codex CLI directly. Production opens a structured handoff that works with your Codex session. Every generated draft remains editable, and an Undo AI draft action restores the previous email.
Upload PNG, JPEG, GIF, or WebP images directly from an image block, paste a public HTTPS image URL, or describe a visual and choose Generate with Codex during local development. When writing the complete email, select Include one original image only when the message needs a visual. It is off by default because image generation adds time. Local Codex can create and store the image before the draft reaches the canvas. A production Codex handoff preserves the image brief so you can generate and upload the finished asset from the image block. Mirin uses the existing CRM asset bucket and email asset domain, so a separate Cloudflare bucket is not required. The core message and call to action always remain live text. Every generated image is wide, contains no essential text, and requires descriptive alt text so the email still works when images are blocked.
Safety checks remain active
Mirin rechecks global suppression, unsubscribe status, active list membership, content, sender readiness, and proof status before delivery. Previewing, saving, and sending a proof do not start a broadcast. You can pause or cancel an active send from its campaign page.