Cynx Engage. An AI email marketing platform that writes, sends and measures campaigns.
We built Cynx Engage, an AI email marketing SaaS first built for The Ice Butcher: pick a date or a holiday, Claude drafts the email, you polish it in a visual builder, and it sends through AWS SES with real open and click tracking.
- First client
- The Ice Butcher
- AI
- Anthropic Claude
- Sending
- AWS SES
- Stack
- React + FastAPI

What Cynx Engage needed.
The Ice Butcher sells around dates that matter: holidays, seasons and events, each one a reason to email their clients. They wanted a tool that turns a date into a finished, on-brand campaign and sends it safely to the right people.
It grew into Cynx Engage, a multi-account SaaS with its own billing that other businesses can use too.
The product, feature by feature.
- 01
Date-driven campaigns
Pick a date or holiday and start a campaign for it. One active send per campaign and per day keeps the calendar clean.
- 02
Claude writes the email
Prompts carry the brand kit and brand voice, so drafts come out on-brand, streamed as they are written.
- 03
Visual email builder
Drag-and-drop editing, with the HTML made safe for Gmail and Outlook in the preview and again at send time.
- 04
Server-side sending
Schedules and “send now” run as server jobs through AWS SES, in chunks with live progress, pause, resume and stop. Closing the laptop never stops or duplicates a send.
- 05
One copy per person
A per-campaign ledger guarantees each person gets a campaign at most once, across retries and reschedules. Resends need an explicit confirmation.
- 06
Do-not-email list
Unsubscribes, spam complaints and hard bounces feed one suppression list, and every email carries a signed unsubscribe link.
- 07
Honest analytics
Open and click rates come from real SES delivery events, never estimates. With no data, the app says “No data yet”.
- 08
Brand gallery
Brand images sync into a shared gallery for campaigns, with Cloudinary handling uploads.
The stack.
The outcome.
- A campaign goes from a date on the calendar to a finished, on-brand email without a blank page.
- Sending is safe by design: server-side jobs, one copy per person and a real block list.
- Analytics measured from delivery events, not estimates.
- Built for The Ice Butcher, grown into a SaaS other businesses can use.

