1
Know what to look for
Read the ways a website breaks after a deploy and why websites break without going offline.
Deploy, Regression & Silent Failure Guides
Guides to the failures that ship with a release: layouts that shift, pages that go blank, scripts and APIs that fail in the browser, redirects that loop. What causes them, and how to catch them within minutes of a deploy.
Start here
Most production incidents on websites are not outages. They are regressions: something that worked yesterday stopped working after a deploy, a plugin update, or a change on a third-party service. The server stays healthy, so they go unnoticed until someone complains.
Start with the ways a website breaks after a deploy for the big picture, then use the post-deploy and launch checklists as runbooks. The deeper guides cover specific failure types when you are debugging one.
Suggested reading path
Pick the step that matches where you are.
2
Build a post-deploy routine
Use the post-deploy monitoring guide and the pre-launch checklist as repeatable runbooks.
3
Automate it in the pipeline
The CI/CD guide covers triggering checks after each release instead of waiting for the next schedule.
4
Debug a specific failure
Blank pages, JavaScript errors, API failures, third-party scripts, and redirects each have their own guide.
All guides in this topic
Ordered from the most common problems to deeper reference material.
Article
5 Ways a Website Breaks After a Deploy
Why a website breaks after deploy without going down: the 5 most common post-deploy failures uptime monitors miss, and how to catch them before your users do.
Read 5 Ways a Website Breaks After a DeployArticle
Post-Deploy Monitoring: What to Check After Every Deploy
Deploys are the riskiest moment for your website. Learn how deployment monitoring catches post-deploy regressions within minutes, before users find them.
Read Post-Deploy Monitoring: What to Check After Every DeployArticle
Website Monitoring Checklist: Before You Launch
A practical website monitoring checklist covering uptime, SSL, visual regression, and user journey monitoring — everything to set up before and after launch.
Read Website Monitoring Checklist: Before You LaunchArticle
CI/CD Website Monitoring
How to fit website monitoring into CI/CD: verify each deploy in production, catch regressions the moment they ship, and turn monitoring into a post-deploy safety net.
Read CI/CD Website MonitoringArticle
What Is Visual Regression Testing?
Visual regression testing catches layout and UI changes that break how your site looks. Here's how it works and why it matters for non-technical website owners.
Read What Is Visual Regression Testing?Article
Why Websites Break Without Going Offline
Learn why websites can break without going fully offline and how website health monitoring helps detect silent failures.
Read Why Websites Break Without Going OfflineArticle
What Causes Blank Pages on Websites?
Learn what causes blank pages on websites and how website health monitoring can detect blank screens even when the server returns 200 OK.
Read What Causes Blank Pages on Websites?Article
How to Monitor JavaScript Errors on a Website
Learn how to monitor JavaScript errors on important website pages so front-end failures do not break forms, checkout, signup, or page rendering.
Read How to Monitor JavaScript Errors on a WebsiteArticle
How to Monitor Third-Party Scripts on Your Website
Learn how to monitor third-party scripts on your website so a broken tag, chat widget, or payment script gets caught before it breaks pages for visitors.
Read How to Monitor Third-Party Scripts on Your WebsiteArticle
How to Monitor API Failures That Break Web Pages
Learn how to monitor API failures that break web pages, including failed XHR and Fetch calls, missing data, slow dependencies, and broken customer actions.
Read How to Monitor API Failures That Break Web PagesArticle
API Monitoring: The Endpoints Your Website Depends On
API monitoring for websites: third-party API failures silently break pages. Learn how to monitor the endpoints your site depends on and catch failures first.
Read API Monitoring: The Endpoints Your Website Depends OnArticle
How to Monitor Website Redirects
A redirect can send your visitors to a page you do not control while uptime stays green. Learn how to monitor website redirects and catch off-site landings.
Read How to Monitor Website RedirectsRelated NorthDuty pages
Product pages, tools, and comparisons connected to this topic.
Feature
Deployment Monitoring
Automatically run health checks, visual diffs, user journeys, and API monitors the moment your site is deployed or your CMS publishes a change.
Explore Deployment MonitoringFeature
Visual Regression Monitoring
Screenshot-based visual regression testing and website change detection for key pages — get pixel diffs on design, content, and layout changes, no code required.
Explore Visual Regression MonitoringFeature
JavaScript Error Monitoring
NorthDuty detects JavaScript errors and console.error messages from a real browser on every health check — so front-end failures are visible before customers report them.
Explore JavaScript Error MonitoringFeature
API Monitoring
NorthDuty finds the critical APIs your site depends on and suggests monitors for them. Add an endpoint, confirm the fields it should return, and get alerted when it breaks.
Explore API MonitoringTool
robots.txt Tester
Free robots.txt tester and validator. Check if a URL is blocked for Googlebot or any crawler and see every rule and sitemap line. Replaces Google's old tester.
Open robots.txt TesterFrequently Asked Questions
Answers to common questions about NorthDuty and website monitoring.
What should I check right after a website deploy?
The homepage and top landing pages render correctly, key journeys like checkout, signup, and forms complete, there are no new JavaScript errors or failed API calls, redirects resolve, and robots.txt did not change. Visual diffs against the previous version catch layout breaks quickly.
How is visual regression testing different from monitoring?
Visual regression testing compares screenshots in a test environment before release. Visual monitoring compares screenshots of the live site on a schedule and after deploys, which also catches changes caused by content edits, plugins, and third-party scripts.
Call To Action
Start monitoring your website with NorthDuty today.
Trigger NorthDuty after every deploy to re-check pages, journeys, and visual diffs, so regressions surface in minutes instead of support tickets.
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