LukStack Uptime Monitor is a lightweight yet powerful website monitoring solution built for agencies, freelancers, and web professionals who manage multiple websites.

Track uptime, response times, and SSL certificate expiration for all your client sites from a single WordPress dashboard. When something goes wrong, you will know immediately through email notifications or webhook integrations with Slack, Discord, and other services.

Reliable Monitoring Out of the Box

Unlike plugins that rely on WordPress Cron (which only runs when someone visits your site), LukStack Uptime Monitor includes a built-in remote cron server operated by the plugin author and hosted on AWS in the EU (Frankfurt) region. Your site is automatically registered on plugin activation and the server triggers your monitoring checks every minute — reliably, even on low-traffic sites. No personal data is transmitted. No third-party cron services like cron-job.org or UptimeRobot required.

Free Plan Features

Uptime Monitoring – Automatic checks every 15 minutes
Monitor up to 2 websites
Webhook Support – Native integration with Slack, Discord, Microsoft Teams, and generic webhooks
Manual Checks – Test any site instantly with one click
Dashboard Widget – Quick status overview right on your WordPress dashboard

Pro Plan Features

Everything in Free
Monitor up to 100 websites
5 minute check interval for faster downtime detection
SSL Certificate Monitoring – Get warned before certificates expire
Website Performance Tracking – Monitor response times with millisecond precision

Who Is This For?

Web Agencies managing client websites
Freelancers maintaining multiple projects
Site Owners who want peace of mind
DevOps Teams needing a simple monitoring solution

How It Works

Add a website URL to monitor
LukStack Uptime Monitor checks the site automatically
If the site goes down or returns an error, you get notified
When the site recovers, you get a recovery notification

Webhook Integrations

LukStack Uptime Monitor automatically formats notifications for popular services:

Slack – Rich message attachments with color-coded severity
Discord – Embedded messages with status information
Microsoft Teams – Via generic webhook connector
Zapier / Make – JSON payload for custom automations

Privacy

LukStack Uptime Monitor stores the URLs you choose to monitor and their status data. No personal information (admin emails, user accounts, site content) is collected by the plugin itself.

The plugin does transmit data to the following external services:

LukStack Cron Server (operated by the plugin author, hosted on AWS EU Frankfurt) — receives your site URL and a locally generated shared secret on plugin activation, then triggers monitoring checks on your site every minute. See the External services section below for details.
Freemius (license management and opt-in usage tracking) — anonymized data only when you explicitly opt in. See https://freemius.com/privacy/
Webhook URLs (Slack, Discord, etc.) — only when you configure them and only when a monitored site changes status.

All external transmissions are described in detail in the External services section below.

External services

This plugin connects to external services as part of its core monitoring functionality. Below is a description of each service, what data is sent, and when.

Monitored Websites

LukStack Uptime Monitor sends HTTP requests to the website URLs you add for monitoring. This is the core functionality of the plugin and is required to check uptime and response times. An SSL connection on port 443 is also made to check the SSL certificate expiration date for HTTPS sites (Pro). These requests are sent automatically by the built-in cron server (see below) and when you manually click “Check now”. The data sent is a standard HTTP GET request with a custom user agent header. No personal data is transmitted.

LukStack Cron Server

This plugin connects to the LukStack cron server to ensure reliable monitoring checks even when your WordPress site has no visitors. Because no dedicated privacy policy URL is published for this service, the full data-handling details are documented below.

Service operator

Operated by Luk Meyer (plugin author). Contact: via the WordPress.org support forum for this plugin (https://wordpress.org/support/plugin/lukstack-uptime-monitor/).

Hosting and location

Hosted on Amazon Web Services (AWS), region eu-central-1 (Frankfurt, Germany). Data does not leave the EU. The service uses AWS Lambda, AWS DynamoDB, and AWS EventBridge Scheduler. AWS acts as a data processor under a standard data processing agreement.

Server endpoint: https://gt5zheubf8.execute-api.eu-central-1.amazonaws.com

What data is transmitted FROM your site TO the cron server

On plugin activation and when an admin visits the WordPress admin (throttled to at most once per hour):

Your site URL (value of WordPress home_url())
A 48-character shared secret, randomly generated on your site, stored in your own wp_options table. This secret is used only to authenticate incoming trigger requests. It is not a WordPress password or account credential.
The plugin version (e.g. “2.2.0”)

No personal data, no admin email, no user account information, no site content, no visitor data, and no credentials are transmitted.

What data is transmitted FROM the cron server TO your site

Every minute, the cron server sends an HTTP POST request to the REST endpoint /wp-json/lukstack/v1/trigger on your site, authenticated via the X-LukStack-Secret header. The request body is empty. The sole purpose of this request is to trigger the plugin’s internal monitoring logic.

What data is stored on the cron server

Site URL
Shared secret (needed to authenticate triggers — transmitted over HTTPS only)
A SHA-256 hash of the site URL used as record key
Plan type (Free or Pro) — used to gate trigger frequency server-side
Timestamps: registration time, last successful trigger, last failed trigger, consecutive failure counter
Last error message if any

No logs of monitored sites, no uptime data, no visitor data, no personal data.

Data retention

Data is kept only as long as the plugin is installed on your site. When the plugin is deleted from your WordPress installation, the site is marked inactive on the cron server after approximately 100 consecutive failed trigger attempts (about 100 minutes) and no further requests are sent. Inactive records may be purged periodically.

Your rights and how to exercise them

You can at any time:

Disable the remote cron by deactivating the plugin — triggers stop, but the record remains until auto-expiry.
Request deletion of your site’s record by posting in the plugin’s WordPress.org support forum with your site URL (or a hash of it). Records are typically deleted within 7 days of a confirmed request.
Rotate the shared secret by re-registering (the settings page exposes a “Force re-register now” button when WP_DEBUG is enabled in your wp-config.php).

Security

All transmissions are over HTTPS (TLS).
Incoming triggers to your site are validated using hash_equals() (constant-time comparison) to prevent timing attacks.
The shared secret is stored with autoload disabled and is not exposed in the admin UI unless WP_DEBUG is enabled.

Legal basis (GDPR)

The processing described above is necessary for the performance of the service you enabled by installing this plugin (Art. 6 (1) (b) GDPR). Only technical identifiers (URL, secret, timestamps) are processed; no special categories of personal data are involved.

Freemius

This plugin uses Freemius SDK for license management, usage tracking (opt-in only), and the upgrade flow. When a user opts in, anonymized data such as the site URL, WordPress version, PHP version, and plugin version may be sent to Freemius servers. Users can opt out at any time.

This service is provided by Freemius, Inc.
Terms of Service: https://freemius.com/terms/
Privacy Policy: https://freemius.com/privacy/

Slack (optional)

If you configure a Slack webhook URL in the plugin settings, LukStack Uptime Monitor sends POST requests to the Slack Incoming Webhooks API when a monitored site changes status (goes down, recovers, or has SSL issues). The data sent includes the website URL, its status, response time, and a timestamp. No personal data is transmitted.

This service is provided by Slack Technologies, LLC / Salesforce, Inc.
Terms of Service: https://slack.com/terms-of-service
Privacy Policy: https://slack.com/privacy-policy

Discord (optional)

If you configure a Discord webhook URL in the plugin settings, LukStack Uptime Monitor sends POST requests to the Discord Webhooks API when a monitored site changes status. The data sent includes the website URL, its status, response time, and a timestamp. No personal data is transmitted.

This service is provided by Discord, Inc.
Terms of Service: https://discord.com/terms
Privacy Policy: https://discord.com/privacy

Generic Webhooks (optional)

You may configure any third-party webhook URL (e.g. Microsoft Teams, Zapier, Make, or a custom endpoint). When a monitored site changes status, a POST request with a JSON payload is sent to that URL. The data sent includes the website URL, its status, response time, and a timestamp. No personal data is transmitted. Please refer to the terms of service and privacy policy of the respective service you configure.

Additional Information

Requirements

WordPress 5.8 or higher
PHP 7.4 or higher
PHP extensions: curl, openssl, json

Support

For support questions, please use the WordPress.org support forum for this plugin.

Credits

Developed by Luk Meyer.