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IT

Catch bugs before your users do.

Agents use every page of your app in a real browser and show you each failure, with the proof to reproduce it.

Try it on our sample app
The IT department for Acme Notes, our sample app: “16 things break for customers on 4 pages, 8 of them to fix first.” The fixes are listed in order, the first one open beside them.

How a bug is found

Each finding says what happened and what the browser saw, and comes with a fix your coding agent can apply.

The front page of Acme Notes, our sample app, with its “Get started free” button ringed.
The console’s detail for one of IT’s findings on Acme Notes: “The main button does nothing when pressed”, with what the browser saw and the fix.

  1. Presses every button

    One at a time, on a fresh page. Anything that looks like a payment or a delete is left alone.

  2. Records what happened

    The “Get started free” button does nothing a visitor can see when clicked: no navigation, and no change on the page. It sends no request either, so nothing is wired to it.

  3. Suggests a fix

    Every finding comes with a prompt for your coding agent, and a re-check to confirm the fix worked.

27 findings from one free run on Acme Notes

Acme Notes is our sample app, with bugs planted on purpose. Across five pages, on desktop and phone, 16 of them break things for customers.

Broken flows

Dead buttons, forms that won’t send, links to nowhere and scripts that crash on load.

  • A form cannot be submitted at alllanding, pricing
  • A link leads nowherelanding, pricing, settings
  • The page hits an error in its code as it loadspricing

Lost saves

It saves a change, then checks from a fresh browser that the change was kept.

This browserDisplay name changedSaved
A clean browser, 5 seconds laterDisplay name: Maya ChenUnchanged
  • The save says it saved, and it did notsettings

Security

Exposed keys, passwords over plain http, unsafe cookies and libraries with known holes.

  • A secret key is visible in your website’s codelanding, pricing, login
  • A password field is sent without encryptionlogin
  • A sign-in cookie is missing a security settinglogin

Accessibility

Every page against WCAG 2.2, with axe-core and checks of our own.

98/100 accessibility
  • A link has no readable textlanding, pricing
  • A piece of text is hard to read against its backgroundlanding
  • The page changes and a screen reader is never toldlanding, pricing, login

Speed

How fast each page loads, how much it jumps and how quickly the server answers.

91/100 performance
  • An image is far larger than the space it fillslanding
  • The page is heavy to downloadlanding

On a phone

Every page again at phone width, for sideways scrolling and buttons too small to tap.

  • Part of the page is wider than a phone screenpricing
  • Buttons or links too small to tap on a phonelanding, pricing, app, settings

Regression checks

Confirm a finding and it becomes a check that runs every time.

  1. Confirmed

    You mark the bug as real while it is still there.

  2. Seen to fail

    The check fails on the bug, which proves it can see it.

  3. Holding

    You fix it, and the check passes from then on.

  4. Came back

    If the bug returns, the finding reopens as ship-blocking.

Every run also photographs each page and compares it with the last look you accepted. How regression checks work

Standards

The standards and research behind its findings. Each one links to its source.

Limits

  • It can’t judge whether your code is well designed. It reports what your product did when it was used.
  • Speed is measured on our machines, not on your users’ phones.
  • A clean accessibility pass is not conformance. Automated rules cover a minority of the standard.
  • It is not a penetration test or legal advice. It reports what your product shows a visitor, and the rule that asks about it.
See what we catch, and what we miss

Questions

Does it need my code?

No. It opens your app from its address, in a real browser, the way a customer arrives, and reports what the app did.

Can it test the pages behind my login?

Yes. Save a test account and it signs in first. Use a login made for testing, never your own, and never one with billing or admin rights.

Testing behind a login
Will it change anything in my app?

It clicks things, so give it an account whose data you would not miss. It skips payments and anything that cannot be undone, and submits forms with test data only if you switch on Live product writes.

How do I know a fix worked?

Re-check that one finding. A finding you confirm becomes a check on every run, and reopens as ship-blocking if the bug comes back.

How regression checks work

Pricing

Free on every plan, unlimited

Buttons, forms, saves, speed, accessibility, security, phone layout, AI assistant access, a map of your app and re-checks of fixed bugs.

Uses validations

Simulated users who try your app, and an AI review of every page.

See pricing

Other departments

Marketing

See how your pitch lands.

Finance

Know what your app could earn.

Try nth Labs now.

Paste a link to run your first check. No account needed.

Checks that don’t use AI are free on every plan. No card needed. See pricing