Postmark Monitor

Tells you your transactional email stopped — in Slack, before a customer does.
Why he built it

Postmark tells you when an email fails. It doesn't tell you when nothing was sent at all.

That’s the failure mode that actually hurts. A cron job dies, a token expires, a deploy quietly drops the call that sends the receipt — and nothing errors. The dashboard just goes quiet, and you find out days later when a customer asks where their confirmation went.I wanted something watching for the silence, not just the errors. Postmark Monitor checks each server on a schedule and posts to Slack the moment activity stops.
What it helps with

Catch silent failures

Alerts on the absence of email, not just on bounces — the failure that no error log will ever show you.

Watch every server at once

Unlimited Postmark servers monitored from a single dashboard, each with its own schedule.

Control the noise

Per-server check intervals and alert thresholds, plus optional weekend suppression so quiet Saturdays don't page you.

See list damage early

Hard bounces, spam complaints, and manual suppressions from the last 7 days, in one place.

Key Features

Slack alerting

When a server stops sending, Postmark Monitor posts to your Slack webhook. You hear about it in the channel you already watch.

Per-server settings

Check interval from 5 minutes to 24 hours; alert threshold from 5 minutes to 72 hours. Tune each server to how often it’s actually supposed to send.

Runs as a Windows service

Monitoring continues even when nobody is logged in. Set it up once and leave it.

Two ways to run it

A native desktop app, or a small local server so you can open the identical dashboard in a browser from any device on your network — phone, tablet, another PC.

Tokens stay local

Nothing is sent anywhere except Postmark and your own Slack webhook.
What's Supported
Designed to work with Postmark servers of all sizes, with Slack and Postmark integrations for reliable monitoring and alerts.

Supports

Slack

Postmark

Email Alerts

Bring your own SMTP

Also Works With

Any number of Postmark servers, via Postmark server API tokens

Slack incoming webhooks

Windows (installs and runs as a Windows service)

Browser access from any device on the same network — phone, tablet, or another computer

Get PostMark Monitor

Never miss an email alert again.

One time price for $30 and ongoing support is $50