Joel Martinez Seattle

The Workshop · 12

Reply → Slack Relay

A single Cloudflare Worker that turns cold-email replies into rich Slack alerts for any client — one deployment serving everyone, instead of a bespoke webhook each time.

Cloudflare Worker Webhooks Multi-tenant
1
Worker serving every client
~2 min
to onboard a new client — one secret, one webhook
24/7
always-on, serverless, no infrastructure to run

The problem

Every new client wanted the same thing: a Slack ping the moment a prospect replied to a campaign. Building a one-off webhook integration per client meant repeating the same plumbing over and over and maintaining all of it forever.

What I built

One Cloudflare Worker that accepts a per-client path, looks up that client's Slack webhook from Worker secrets, and transforms the incoming reply event into a formatted Slack message — a header, structured fields, the quoted reply, and a button that opens the lead straight in the campaign tool. Adding a client is a single secret plus one webhook configuration.

The result

  • Multiple client slugs live on a single deployment.
  • A new client goes live in about two minutes.
  • Always-on and serverless — nothing to provision, nothing to patch.