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Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
47
GRADE
F
FIX
8
REVIEW
3
PASS
2
INFO
0
Checks
13
2 PASS 3 REVIEW 8 FIX
D
Landmark Structure
Action
1 landmarks
FIX
1 landmarks
Critical::
No <main> landmark found
Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.
Info::
1 <nav> landmark(s) found
Info::
No banner (header) landmark
Info::
No contentinfo (footer) landmark
Warning::
Skip navigation link is missing (WCAG 2.4.1)
Add a skip link as the first focusable element so keyboard users can bypass repeated navigation.
Page Structure — as a screen reader sees it
BANNER (missing!) NAV MAIN (missing!) CONTENTINFO (missing!)

Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.

Why this matters

Without a <main> landmark, screen-reader users can't skip past the navigation to the page content — every page starts with re-reading the menu.

Learn more ▾

The <main> element marks the page's primary content area. Assistive tech offers a 'jump to main' shortcut — but only if <main> exists. Without it, every page navigation forces re-reading the header. Wrap your primary content in a single <main>.

Source: WAI-ARIA / WCAG 2.4.1

Add a skip link as the first focusable element so keyboard users can bypass repeated navigation.

Why this matters

Without a skip-nav link, keyboard users tab through every nav item before reaching content — every page, every visit.

Learn more ▾

WCAG 2.4.1 (Bypass Blocks) requires a mechanism to skip past repeated content. The standard implementation is a 'Skip to main content' link that's the first focusable element, visually hidden until focused. Three lines of HTML + four of CSS.

Source: WCAG 2.1 SC 2.4.1

D
Heading Hierarchy
Action
65 headings, 2 skip(s)
FIX
65 headings, 2 skip(s)
Critical::
No H1 heading found
Every page should have one H1 that describes the page content.
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H4 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
  • H4 Enjoy long-term maintainable software you can rely on
  • H4 Declarative, statically typed code.
  • H2 Try it!
  • H3 Got 5 minutes?
  • H2 Why Haskell?
  • H3 A new paradigm
  • H3 Composition and predictability
  • H3 Declarative
  • H3 Performance
  • H3 Abstraction
  • H3 Excellent tooling
  • H2 Videos
  • H5 Escape from the ivory tower: The Haskell journey, by Simon Peyton-Jones skipped
  • H5 Functional Programming & Haskell, by Computerphile / John Hughes
  • H5 Past and Present of Haskell – Interview with Simon Peyton Jones
  • H5 Functional Programming in Haskell, by Graham Hutton
  • H5 What is a Monad? by Computerphile / Graham Hutton
  • H5 The Haskell Unfolder: Dijkstra's shortest paths, by Andres Löh and Edsko de Vries
  • H2 Testimonials
  • H4 IOHK skipped
  • H5 Smart contract systems are largely about programming languages, and when it comes to programming languages work there is no competitor to Haskell.
  • H4 Scarf
  • H5 Haskell powers Scarf's backend, helping us move fast and not break things. It offers unparalleled maintainability, so we can quickly and safely adapt our system to the moving target of customer demand
  • H4 Fission
  • H5 Haskell enables Fission to build rock solid, maintainable, and performant services and tools.
  • H4 Calabrio
  • H5 At Calabrio we use Haskell to build our Customer Intelligence and Analytics Platform (Calabrio Advanced Reporting). Haskell's robust typing and semantics offer us important guarantees for our data ope
  • H4 Stack Builders
  • H5 Haskell makes it possible to maintain an EdTech platform in 23 languages for more than 70K users from one of the largest multinational financial services corporations.
  • H4 Bitnomial
  • H5 Haskell gives us huge leverage over our complex business domain while allowing us to stay nimble and innovate. The type system allows us to integrate new knowledge quickly and refactor our sizeable co
  • H4 CentralApp
  • H5 We use Haskell... Because solving complex problems well requires the best tools in the business.
  • H4 finn.no
  • H5 FINN.no is an online classified ad site, and we use Haskell in production. It allows us to express business logic with focus on correctness and we benefit greatly from the safe and joyful refactoring
  • H4 Serokell
  • H5 Haskell enables us to build reliable, performant, and maintainable applications for our clients in biotech, fintech, and blockchain.
  • H4 NoRedInk
  • H5 The highest-traffic features of noredink.com are now served via Haskell. We've seen a huge performance improvement compared to what was previously doing that work as well as a massive reduction in pro
  • H4 Bellroy
  • H5 We've found the stability, maintainability and performance of Haskell to be exceptional and we look forward to more of that in the years to come.
  • H4 Imagine AI
  • H5 ImagineAI is a smart code generator written in Haskell that instantly turns your app spec into clean Django and Node source code.
  • H4 Foxhound Systems
  • H5 At Foxhound Systems, we build custom software for a variety of clients. Haskell is our first choice for building production systems because it is unrivaled in the combination of developer productivity
  • H4 Hasura
  • H5 Haskell is an ideal prototyping tool, when we want to build an MVP and get a prototype out as quickly as possible...Haskell lets us be precise when we need to be, and fast when we want to be.
  • H4 Scrive
  • H5 Scrive uses Haskell to build secure and scalable e-signing, programmable document workflows and customer onboarding solutions. The Haskell language comes with a developer community that is a pleasure
  • H4 Mercury
  • H5 Mercury offers banking for startups — at any size or stage. We use Haskell to meet our customers' high standards for correctness and security.
  • H4 e-bot7
  • H5 Haskell allows us to create powerful, reliable software with confidence. It allows us to detect unwanted behavior before it shows up in our production environment.
  • H4 HubSpot
  • H5 Haskell drives our data synchronization engine, delivering highly configurable two-way sync to our customers. It enables us to build and evolve complex software with confidence at HubSpot scale.
  • H2 Features
  • H3 Statically typed
  • H3 Purely functional
  • H3 Type inference
  • H3 Concurrent
  • H3 Lazy
  • H3 Packages
  • H2 Sponsors
  • H3 Maintenance of this site
  • H3 Psst! Looking for the wiki?

Every page should have one H1 that describes the page content.

Why this matters

No H1 means screen-reader users can't identify the page's primary topic, and Google's content-extraction degrades.

Learn more ▾

The H1 is the document title for assistive tech and a strong signal to search engines about page topic. Pages without one force screen readers to fall back to the <title> attribute or page chrome. Add a single H1 that names the page's primary subject.

Source: WCAG 2.4.6 / Google Search Central

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

F
404 Error Page
Action
HTTP 404, bare page
FIX
HTTP 404, bare page
Info::
Correct 404 status code returned
Got: HTTP 404
Warning::
Bare server default 404 page
The 404 page has no custom styling. Users hitting a broken link see a generic error with no way to navigate back. Add a custom 404 page with your site navigation and a search bar.
404 Page Quality Default 404 Page
Status Code HTTP 404 ✓Page Title 404 Not Found ✓Custom Styling ✗Navigation ✗Homepage Link ✗Search Form ✗
F
Favicon & Branding
Action
1 icon(s) detected
FIX
1 icon(s) detected
Warning::
No favicon.ico at site root
Some older browsers, bookmark tools, and RSS readers look for /favicon.ico. Add one as a fallback.
Info::
HTML icon links detected
Info::
No apple-touch-icon detected
iOS devices use this when users add your site to their home screen. Add <link rel='apple-touch-icon' sizes='180x180' href='/apple-touch-icon.png'>.
✗ favicon.ico Missing
✓ PNG Icons Present
✗ Apple Touch Missing
✗ SVG Favicon Missing
✗ Manifest Icons Missing
✗ Multiple Sizes Missing
D
Web Manifest
Action
Not found
FIX
Not found
Info::
No web manifest found
No manifest at standard paths (/manifest.json, /site.webmanifest). A manifest is optional but enables PWA features like home screen installation and standalone display.

No web manifest found.

D
Dark Mode Support
Action
No dark mode signals
FIX
No dark mode signals
Info::
No dark mode signals detected
Consider adding CSS with @media (prefers-color-scheme: dark) and <meta name='color-scheme' content='light dark'>.
Info::
Detection limited to meta tags and inline styles
External CSS files may contain prefers-color-scheme rules not visible to this scan.
Dark ModeNo Dark Mode Detected
color-scheme meta Not set ✗Dark theme-color Not set ✗CSS indicators Not detected ✗

Detection limited to meta tags and inline styles.

D
Print Stylesheet
Action
No print styles
FIX
No print styles
Info::
No print-specific styles detected
When users print this page, they get the screen layout including navigation and non-essential elements. Add @media print rules to hide navigation and optimize layout for paper.
Print Stylesheet No Print Styles
Print stylesheet Not found ✗Inline @media print Not detected ✗
F
Navigation UX
Action
No navigation patterns
FIX
No navigation patterns
Info::
1 navigation landmark(s) detected
Info::
No breadcrumbs, search, or skip link detected
These navigation aids help users orient themselves and find content efficiently, especially on large sites.
Breadcrumbs
Search
Skip Link
Labeled Navigation 1 <nav> element(s)
Back to Top
Hamburger Menu
Sticky Navigation Cannot reliably detect (CSS-based)
1 of 6 testable patterns navigation patterns detected. Limited navigation support. Consider adding breadcrumbs, search, and skip link.
C
Color Contrast (Screenshot)
Action
20 text elements analyzed, 20 fail WCAG AA
REVIEW

Analyzes text contrast against the actual rendered page, including background images, gradients, and overlays that CSS-based tools cannot detect.

0 pass 20 fail WCAG AA
h2 Try it!
1.53:1
#000000
on
#3F1C5B
needs 3.0:1 (large text)
24px · mid-page
h2 Why Haskell?
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Videos
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Testimonials
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Features
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Sponsors
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
24px · bottom of viewport
h3 Got 5 minutes?
1.83:1
#000000
on
#4F256F
needs 3.0:1 (large text)
19px · mid-page
h3 A new paradigm
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Composition and predictability
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Declarative
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Performance
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Abstraction
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Excellent tooling
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Statically typed
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Purely functional
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Type inference
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Concurrent
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Lazy
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Packages
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Maintenance of this site
1.43:1
#000000
on
#361D49
needs 3.0:1 (large text)
19px · bottom of viewport
Show all checked elements (20)
ElementRatioRequiredFGBGResult
h2 Try it!1.53:13.0:1
#000000
#3F1C5B
Fail
h2 Why Haskell?1.43:13.0:1
#000000
#361D49
Fail
h2 Videos1.43:13.0:1
#000000
#361D49
Fail
h2 Testimonials1.43:13.0:1
#000000
#361D49
Fail
h2 Features1.43:13.0:1
#000000
#361D49
Fail
h2 Sponsors1.43:13.0:1
#000000
#361D49
Fail
h3 Got 5 minutes?1.83:13.0:1
#000000
#4F256F
Fail
h3 A new paradigm1.43:13.0:1
#000000
#361D49
Fail
h3 Composition and pred…1.43:13.0:1
#000000
#361D49
Fail
h3 Declarative1.43:13.0:1
#000000
#361D49
Fail
h3 Performance1.43:13.0:1
#000000
#361D49
Fail
h3 Abstraction1.43:13.0:1
#000000
#361D49
Fail
h3 Excellent tooling1.43:13.0:1
#000000
#361D49
Fail
h3 Statically typed1.43:13.0:1
#000000
#361D49
Fail
h3 Purely functional1.43:13.0:1
#000000
#361D49
Fail
h3 Type inference1.43:13.0:1
#000000
#361D49
Fail
h3 Concurrent1.43:13.0:1
#000000
#361D49
Fail
h3 Lazy1.43:13.0:1
#000000
#361D49
Fail
h3 Packages1.43:13.0:1
#000000
#361D49
Fail
h3 Maintenance of this …1.43:13.0:1
#000000
#361D49
Fail

Methodology: The top 20 text elements by font size were checked. Background color was sampled from the desktop screenshot using a 5-point pattern. WCAG 2.1 AA requires 4.5:1 for normal text and 3:1 for large text.

B
Lighthouse Accessibility Audits
Score 83/100 — 5 failing, 21 passed
REVIEW
83

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
nav.navbar > div.container > div.navbar-header > button.navbar-toggle nav.navbar > div.container > div.navbar-header > button.navbar-toggle

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.span6 > div#console > div.jquery-console-inner > textarea.jquery-console-typer div.span6 > div#console > div.jquery-console-inner > textarea.jquery-console-typer

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
primes div.branding > div.code-sample > pre > span.hs-definition

These are opportunities to improve the legibility of your content.

Navigation

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Escape from the ivory tower: The Haskell journey, by Simon Peyton-Jones div.span3 > a.thumbnail > div.caption > h5
Calabrio div.thumbnail > div.testimonial-caption > a > h4

These are opportunities to improve keyboard navigation in your application.

Best practices

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable
○Interactive elements indicate their purpose and state
○The page has a logical tab order
○Visual order on the page follows DOM order
○User focus is not accidentally trapped in a region
○The user's focus is directed to new content added to the page
○HTML5 landmark elements are used to improve navigation
○Offscreen content is hidden from assistive technology
○Custom controls have associated labels
○Custom controls have ARIA roles
●`[aria-*]` attributes match their roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`s have all required `[aria-*]` attributes
●Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
●`[role]`s are contained by their required parent element
●`[role]` values are valid
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●Image elements have `[alt]` attributes
●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
●ARIA attributes are used as specified for the element's role
●Elements use only permitted ARIA attributes
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links are distinguishable without relying on color.
●Links have a discernible name
●Touch targets have sufficient size and spacing.
●Deprecated ARIA roles were not used
●Identical links have the same purpose.
●Elements with visible text labels have matching accessible names.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
○`[aria-hidden="true"]` elements do not contain focusable descendents
○ARIA input fields have accessible names
○ARIA `meter` elements have accessible names
○ARIA `progressbar` elements have accessible names
○Elements with the `role=text` attribute do not have focusable descendents.
○ARIA toggle fields have accessible names
○ARIA `tooltip` elements have accessible names
○ARIA `treeitem` elements have accessible names
○The page contains a heading, skip link, or landmark region
○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
○Definition list items are wrapped in `<dl>` elements
○ARIA IDs are unique
○No form fields have multiple labels
○`<frame>` or `<iframe>` elements have a title
○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
○Input buttons have discernible text.
○`<input type="image">` elements have `[alt]` text
○Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
○List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○No element has a `[tabindex]` value greater than 0
○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
○`[lang]` attributes have a valid value
○`<video>` elements contain a `<track>` element with `[kind="captions"]`
○Tables have different content in the summary attribute and `<caption>`.
○All heading elements contain content.
○Uses ARIA roles only on compatible elements
○Image elements do not have `[alt]` attributes that are redundant text.
○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`<td>` elements in a large `<table>` have one or more table headers.
A
Alt Text Quality
1 of 27 images have issues
PASS
1 of 27 images have issues
Critical::
1 image(s) missing alt attribute
Images without alt text are invisible to screen readers.
Info::
6 decorative image(s) correctly marked
Info::
20 image(s) with good alt text
27 images 20 good alt text 6 decorative 1 missing
IssueCount
missing1 image(s)

Images without alt text are invisible to screen readers.

Why this matters

Each image without alt text is a WCAG 1.1.1 failure — invisible to screen-reader users, lost from Google Image Search.

Learn more ▾

WCAG 2.1 Level A requires text alternatives for non-decorative images. Empty alt='' is fine for decorative; meaningful images need descriptive text. Common fixes: CMS audit + bulk add, build-time linter (alt-text-required ESLint rule), CI gate on Lighthouse a11y score.

Source: WCAG 2.1 SC 1.1.1 / WebAIM Million Report

A
Form Accessibility
1 of 1 controls have issues
PASS
1 of 1 controls have issues
Critical::
1 control(s) without accessible label
Form controls need a <label>, aria-label, or aria-labelledby for screen readers.
Got: <textarea>
1 controls
0 labeled
0 placeholder only
1 unlabeled
ControlTypeLabelMethod
textareatextarea(none)none

Form controls need a <label>, aria-label, or aria-labelledby for screen readers.

<textarea>

Why this matters

Form controls without labels — assistive tech announces 'edit text' with no context; users can't complete forms.

Source: WCAG 2.1 SC 3.3.2

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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