Workflows Can Now Notify Slack and Email When an Approval Is Waiting
Approval steps can now ping a Slack webhook or send an email the moment they start waiting, instead of relying on someone to go check the app.
Approval steps in Workflows had one gap until now: once a run paused waiting for a human decision, nothing told anyone it was waiting. The approver had to know to go check. That changes with two new, optional fields on every approval step: a Slack webhook URL and an email address, either of which can be filled in with values pulled from the workflow's own data.
How it fires
Both notifications go out from inside the same step that pauses the run for approval, so they fire exactly once per approval — Cloudflare Workflows' own replay guarantees make sure a retried or resumed run doesn't send the same ping twice. During a rehearsal run (dry run), neither notification is sent, so testing a workflow never spams a real Slack channel or inbox.
The Slack notification uses the same pattern as the platform's new Slack action step: you supply your own Incoming Webhook URL, Piskes doesn't hold a Slack credential, and the request goes through the same SSRF-safe fetch policy as any other outbound URL call in a workflow. Neither send is allowed to fail the approval step itself — a bad webhook URL or a missing mail configuration means no notification goes out, but the approval still sits there waiting exactly as it would have before.
Email needs a step from Piskes first
Slack notifications work today with nothing extra needed. Email notifications route through the same transactional email provider (Resend) another part of the platform already uses, but the required API key hasn't been configured on the workflow engine yet — so until that's set, an approval step configured with a notification email will simply send nothing rather than error. Slack is the reliable option right now; email support is built and waiting on that configuration step.
Why this matters
Approval steps exist to put a human in the loop before something consequential happens — a payment, a published change, an external message. A notification that fires the instant that gate goes up is what makes "in the loop" mean something in practice, instead of hoping someone remembers to check.