Get an alert when a plugin update will break your site on the next PHP version
Short answer
A site that was ready for the next PHP version last month may not be today: every plugin or theme update can bring new code. A one-time check can’t see that. CompatNav Pro, launching on 31 October 2026, scans again on a schedule and 15 minutes after plugins or themes change, compares each scan with the one before, and sends an email, or a post in Slack, Microsoft Teams or Discord, only when something new will break. Deprecation notices never trigger an alert.
The problem: readiness doesn’t stay true
You checked a site in spring: ready for PHP 8.4. Since then, plugins updated a dozen times, a new plugin was added, the theme changed. Most updates make code more compatible, but not all: a new version can use something that won’t run on the PHP version the host will switch to. A check from spring says nothing about that. The first sign is the host’s switch, and a critical error.
What you’d need to catch it
- A check after every change, not once a year.
- A comparison with the last check, so you see only what’s new.
- An alert only when it matters: something that will stop a page, not every notice.
- No extra work per site, because you look after many.
How CompatNav Pro does it
CompatNav Pro, launching on 31 October 2026, adds this to the free plugin:
- Scheduled scans, weekly or daily, and one scan 15 minutes after plugins or themes are updated, installed or activated (at most one every 6 hours).
- Each scan compared with the one before.
- An email only when something new will break on your target PHP version. Deprecation notices never trigger one. At most one alert a day; a plugin that newly breaks goes out at once.
- Chat alerts (opt-in): a post in Slack, Microsoft Teams or Discord, and a weekly summary if you want one.
At the top of every alert, one sentence says what changed since the last scan, such as a new plugin with one problem that will break.
Everything stays on the site
The scans run on each site’s own server, as with the free plugin: no code, file names or reports are sent anywhere. Alert emails are sent by the site itself, through its own email setup. What Pro sends, and when, is listed on what leaves your site.
Without Pro
Run the free check after every update day, for the PHP version the host will move to, and compare it with last time. It works; it just takes discipline across many sites. The maintenance checklist puts it in a routine, and what uptime monitoring misses explains why monitoring alone won’t catch it.
Key takeaways
- Readiness for the next PHP version changes with every update; a one-time check goes stale.
- CompatNav Pro scans weekly or daily, and 15 minutes after plugins or themes change (at most one such scan every 6 hours).
- Each scan is compared with the one before: you hear only about what’s new.
- Alerts only for new problems that will break; deprecation notices never trigger one; at most one alert a day.
- Email, or Slack, Microsoft Teams and Discord, and everything runs on the site’s own server.
Frequently asked questions
Will I get an email every time a notice appears?
No. Pro alerts only when something new will break on your target PHP version. Deprecation notices never trigger an alert; you can get a weekly summary instead if you want.
What if many things change at once?
At most one alert email a day, with later ones merged in. A plugin that had no problem before and now will break is sent at once.
Can I do this with the free plugin?
You can run the free check by hand after every update day and compare the results yourself. Pro does the schedule, the comparison and the alert for you.
Check your own site before you upgrade
CompatNav is a free WordPress plugin. It reads the code of your plugins and themes on your own server and tells you, in plain words, what will break and what will only show notices on the PHP version you choose. It never changes your code. It can’t see problems that only appear while code runs with real data, so a quick check of your site after the upgrade still matters.
Sources
About the code examples: each output is the real output of the code shown, run with the official PHP builds, without a php.ini, with all errors reported and displayed. Only the file path was replaced by a neutral server path.