C — https://www.haskell.org | BeaverCheck Audit

Site Health

Score: 74 / 100

Based on 8 categories, 0 sections

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

Top Priorities (5)

Content-Security-Policy header is missing

Security › Security Headers

HSTS header is missing

Security › Security Headers

No Content-Security-Policy header found

Security › Content Security Policy

1 button(s) with no accessible text

Accessibility › Link & Button Quality

1 control(s) without accessible label

Accessibility › Form Accessibility

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[![BeaverCheck](https://beavercheck.com/badge?url=https%3A%2F%2Fwww.haskell.org)](https://beavercheck.com/results/1d4fb56b-96ff-6c1c-51fb-3bca47e4c70b)

HTML

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

Accessibility

Best Practices

100

SEO

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

2.09 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

5.15 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

54 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.197

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

2.41 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

5.17 s

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Request	Cache TTL	Transfer Size
www.haskell.org/img/pattern.png	0.0 ms	291.6 KiB
www.haskell.org/img/haskell-uwu.png	0.0 ms	100.5 KiB
www.haskell.org/js/jquery.js	0.0 ms	33.3 KiB
www.haskell.org/fonts/ubuntu-mono-v15-latin-regular.woff2	0.0 ms	27.0 KiB
www.haskell.org/testimonials/logos/mercury.png	0.0 ms	25.6 KiB
www.haskell.org/testimonials/logos/bellroy.png	0.0 ms	23.4 KiB
www.haskell.org/fonts/raleway-v28-latin-700.woff2	0.0 ms	21.1 KiB
www.haskell.org/testimonials/logos/Scrive.png	0.0 ms	19.5 KiB
www.haskell.org/testimonials/logos/stackbuilders.png	0.0 ms	18.6 KiB
www.haskell.org/css/hl.css	0.0 ms	17.0 KiB
www.haskell.org/testimonials/logos/hubspot.png	0.0 ms	16.3 KiB
www.haskell.org/testimonials/logos/fission.png	0.0 ms	15.4 KiB
www.haskell.org/fonts/source-sans-3-v9-latin-regular.woff2	0.0 ms	14.9 KiB
i1.ytimg.com/vi/t1e8gqXLbsU/mqdefault.jpg	7200.0 s	19.8 KiB
www.haskell.org/testimonials/logos/hasura.png	0.0 ms	14.6 KiB
www.haskell.org/testimonials/logos/e-bot7.png	0.0 ms	14.4 KiB
www.haskell.org/testimonials/logos/foxhoundsystems.png	0.0 ms	13.4 KiB
www.haskell.org/testimonials/logos/finn.png	0.0 ms	12.8 KiB
www.haskell.org/testimonials/logos/iohk.png	0.0 ms	11.2 KiB
www.haskell.org/testimonials/logos/noredink.png	0.0 ms	11.0 KiB
i1.ytimg.com/vi/LnX3B9oaKzw/mqdefault.jpg	7200.0 s	14.0 KiB
www.haskell.org/testimonials/logos/centralapp.png	0.0 ms	10.5 KiB
i1.ytimg.com/vi/4RuLzL_q0zs/mqdefault.jpg	7200.0 s	13.4 KiB
www.haskell.org/testimonials/logos/imagineai.png	0.0 ms	9.6 KiB
www.haskell.org/testimonials/logos/calabrio.png	0.0 ms	8.5 KiB
i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg	7200.0 s	10.9 KiB
www.haskell.org/js/bootstrap.min.js	0.0 ms	7.8 KiB
i1.ytimg.com/vi/WHVMjMIJnB4/mqdefault.jpg	7200.0 s	10.0 KiB
www.haskell.org/js/jquery.console.js	0.0 ms	7.2 KiB
www.haskell.org/js/tryhaskell.pages.js	0.0 ms	6.8 KiB
www.haskell.org/testimonials/logos/scarf.png	0.0 ms	5.9 KiB
www.haskell.org/testimonials/logos/bitnomial.png	0.0 ms	4.1 KiB
www.haskell.org/testimonials/logos/serokell.png	0.0 ms	3.6 KiB
www.haskell.org/js/tryhaskell.js	0.0 ms	2.8 KiB
www.haskell.org/img/haskell-logo.svg	0.0 ms	1.6 KiB
www.haskell.org/js/home.js	0.0 ms	777 B
www.haskell.org/css/fonts.css	0.0 ms	410 B
cdn.jsdelivr.net/npm/glider-js@1/glider.min.js	604800.0 s	3.2 KiB
cdn.jsdelivr.net/npm/glider-js@1/glider.min.css	604800.0 s	1.1 KiB

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]

items: [map[node:map[type:text value:Total] score:0.19693] map[node:map[boundingRect:map[bottom:805 height:43 left:30 right:381 top:762 width:351] lhId:page-24-SMALL nodeLabel:(click to insert) path:1,HTML,2,BODY,1,DIV,11,DIV,1,DIV,1,DIV,1,DIV,1,DIV,1,DIV,1,DIV,3,DIV,0,DIV,2,P,1,SMALL selector:div#guide > div.indent > p > small.note snippet:<small class="note"> type:node] score:0.119511 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://www.haskell.org/fonts/source-sans-3-v9-latin-regular.woff2]] map[cause:Web font extra:map[type:url value:https://www.haskell.org/fonts/ubuntu-mono-v15-latin-regular.woff2]] map[cause:Web font extra:map[type:url value:https://www.haskell.org/fonts/raleway-v28-latin-700.woff2]]] type:subitems]] map[node:map[boundingRect:map[bottom:2167 height:1240 left:0 right:412 top:927 width:412] lhId:page-23-DIV nodeLabel:Why Haskell? A new paradigm Express your ideas clearly and learn a new way of … path:1,HTML,2,BODY,1,DIV,15,DIV selector:body.page-home > div.wrap > div.features snippet:<div class="features"> type:node] score:0.077419 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2358 height:93 left:20 right:186 top:2265 width:166] lhId:page-18-IMG nodeLabel:div.row > div.span3 > a.thumbnail > img.img-responsive path:1,HTML,2,BODY,1,DIV,17,DIV,1,DIV,1,DIV,1,DIV,1,DIV,5,DIV,1,DIV,1,DIV,1,DIV,1,A,1,IMG selector:div.row > div.span3 > a.thumbnail > img.img-responsive snippet:<img src="https://i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg" alt="" class="img-responsive"> type:node]]] type:subitems]]]

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:26.919 source:map[column:1098 line:15 type:source-location url:https://cdn.jsdelivr.net/npm/glider-js@1/glider.min.js urlProvider:network]] map[reflowTime:3.351 source:map[column:1599 line:15 type:source-location url:https://cdn.jsdelivr.net/npm/glider-js@1/glider.min.js urlProvider:network]] map[reflowTime:2.682 source:map[column:3768 line:15 type:source-location url:https://cdn.jsdelivr.net/npm/glider-js@1/glider.min.js urlProvider:network]] map[reflowTime:0.197 source:map[column:3950 line:15 type:source-location url:https://cdn.jsdelivr.net/npm/glider-js@1/glider.min.js urlProvider:network]] map[reflowTime:0.911 source:map[column:4532 line:15 type:source-location url:https://cdn.jsdelivr.net/npm/glider-js@1/glider.min.js urlProvider:network]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

	URL	Resource Size	Est Savings
Sponsors Fastly's Next Generation CDN provides low latency access for all of H… `body.page-home > div.wrap > div.sponsors`	www.haskell.org/img/pattern.png	291.1 KiB	41.1 KiB
Mercury: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/mercury.png	25.3 KiB	23.7 KiB
Bellroy: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/bellroy.png	23.2 KiB	21.5 KiB
Scrive: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/Scrive.png	19.3 KiB	17.6 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/t1e8gqXLbsU/mqdefault.jpg	19.7 KiB	17.2 KiB
Stack Builders: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/stackbuilders.png	18.4 KiB	16.8 KiB
HubSpot: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hubspot.png	16.1 KiB	14.5 KiB
Fission: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/fission.png	15.2 KiB	13.6 KiB
Hasura: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hasura.png	14.4 KiB	12.8 KiB
e-bot7: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/e-bot7.png	14.2 KiB	12.6 KiB
Foxhound Systems: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/foxhoundsystems.png	13.2 KiB	11.7 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/LnX3B9oaKzw/mqdefault.jpg	14.0 KiB	11.4 KiB
finn.no: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/finn.png	12.6 KiB	11.2 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/4RuLzL_q0zs/mqdefault.jpg	13.3 KiB	10.8 KiB
IOHK: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/iohk.png	11.0 KiB	9.8 KiB
NoRedInk: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/noredink.png	10.8 KiB	9.6 KiB
CentralApp: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/centralapp.png	10.2 KiB	9.1 KiB
Imagine AI: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/imagineai.png	9.4 KiB	8.4 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg	10.5 KiB	7.9 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/WHVMjMIJnB4/mqdefault.jpg	10.0 KiB	7.4 KiB
Calabrio: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/calabrio.png	8.3 KiB	7.4 KiB
Scarf: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/scarf.png	5.7 KiB	5.1 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

lhId: page-22-DIV

nodeLabel: Try it! Type Haskell expressions in here. λ Got 5 minutes? Type help to sta…

path: 1,HTML,2,BODY,1,DIV,11,DIV

selector: body.page-home > div.wrap > div.pattern-bg

snippet: <div class="pattern-bg">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.

title: Preconnected origins

value: no origins were preconnected

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

value: No additional origins are good candidates for preconnecting

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

URL	Transfer Size	Duration
www.haskell.org/css/hl.css	17.0 KiB	240 ms
www.haskell.org/css/fonts.css	410 B
cdn.jsdelivr.net/npm/glider-js@1/glider.min.js	3.2 KiB	150 ms
cdn.jsdelivr.net/npm/glider-js@1/glider.min.css	1.1 KiB	751 ms

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Element	Layout shift score
(click to insert) `div#guide > div.indent > p > small.note`	0.120
Why Haskell? A new paradigm Express your ideas clearly and learn a new way of … `body.page-home > div.wrap > div.features`	0.077

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

TTI

Diagnostics

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Estimated savings: 0.0 ms 4.1 KiB

URL	Transfer Size	Est Savings
www.haskell.org/js/jquery.console.js	7.0 KiB	4.1 KiB

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Estimated savings: 0.0 ms 15.2 KiB

URL	Transfer Size	Est Savings
www.haskell.org/css/hl.css	16.8 KiB	15.2 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

	URL
Calabrio: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/calabrio.png
HubSpot: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hubspot.png
Bitnomial: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/bitnomial.png
Serokell: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/serokell.png
finn.no: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/finn.png
Scarf: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/scarf.png
NoRedInk: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/noredink.png
CentralApp: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/centralapp.png
IOHK: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/iohk.png
Hasura: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hasura.png
Fission: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/fission.png
e-bot7: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/e-bot7.png
Stack Builders: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/stackbuilders.png
Foxhound Systems: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/foxhoundsystems.png
Mercury: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/mercury.png
Imagine AI: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/imagineai.png
Scrive: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/Scrive.png
Bellroy: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/bellroy.png
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/LnX3B9oaKzw/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/4RuLzL_q0zs/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/t1e8gqXLbsU/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/WHVMjMIJnB4/mqdefault.jpg
Haskell `div.row > div.span6 > div.branding > img.img-responsive`	www.haskell.org/img/haskell-logo.svg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/IzQTfh-Iuds/mqdefault.jpg

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Max Potential First Input Delay 110 ms

●Document request latency

●Optimize DOM size

●Font display

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Reduce unused JavaScript

●Avoids enormous network payloads Total size was 858 KiB

●JavaScript execution time 0.2 s

●Minimizes main-thread work 1.1 s

●Avoid long main-thread tasks 4 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 90 ms

●Server Backend Latencies 150 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Avoid multiple page redirects

●Initial server response time was short Root document took 180 ms

○INP breakdown

○User Timing marks and measures

○Avoid non-composited animations

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.

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.

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.

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.

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.

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.

Best Practices

General

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Source	Description
i1.ytimg.com/vi/IzQTfh-Iuds/mqdefault.jpg	`Failed to load resource: the server responded with a status of 404 ()`

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Use a strong HSTS policy

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

100

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

Performance

Accessibility

Best Practices

100

SEO

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

889 ms

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

1.57 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

0 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.035

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

962 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.57 s

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Request	Cache TTL	Transfer Size
www.haskell.org/img/pattern.png	0.0 ms	291.6 KiB
www.haskell.org/img/haskell-uwu.png	0.0 ms	100.5 KiB
www.haskell.org/js/jquery.js	0.0 ms	33.3 KiB
www.haskell.org/fonts/ubuntu-mono-v15-latin-regular.woff2	0.0 ms	27.0 KiB
www.haskell.org/testimonials/logos/mercury.png	0.0 ms	25.6 KiB
www.haskell.org/testimonials/logos/bellroy.png	0.0 ms	23.4 KiB
www.haskell.org/fonts/raleway-v28-latin-700.woff2	0.0 ms	21.1 KiB
www.haskell.org/testimonials/logos/Scrive.png	0.0 ms	19.5 KiB
www.haskell.org/testimonials/logos/stackbuilders.png	0.0 ms	18.6 KiB
www.haskell.org/css/hl.css	0.0 ms	17.0 KiB
www.haskell.org/testimonials/logos/hubspot.png	0.0 ms	16.3 KiB
www.haskell.org/testimonials/logos/fission.png	0.0 ms	15.4 KiB
www.haskell.org/fonts/source-sans-3-v9-latin-regular.woff2	0.0 ms	14.9 KiB
i1.ytimg.com/vi/t1e8gqXLbsU/mqdefault.jpg	7200.0 s	19.8 KiB
www.haskell.org/testimonials/logos/hasura.png	0.0 ms	14.6 KiB
www.haskell.org/testimonials/logos/e-bot7.png	0.0 ms	14.4 KiB
www.haskell.org/testimonials/logos/foxhoundsystems.png	0.0 ms	13.4 KiB
www.haskell.org/testimonials/logos/finn.png	0.0 ms	12.8 KiB
www.haskell.org/testimonials/logos/iohk.png	0.0 ms	11.2 KiB
www.haskell.org/testimonials/logos/noredink.png	0.0 ms	11.0 KiB
i1.ytimg.com/vi/LnX3B9oaKzw/mqdefault.jpg	7200.0 s	14.0 KiB
www.haskell.org/testimonials/logos/centralapp.png	0.0 ms	10.5 KiB
i1.ytimg.com/vi/4RuLzL_q0zs/mqdefault.jpg	7200.0 s	13.4 KiB
www.haskell.org/testimonials/logos/imagineai.png	0.0 ms	9.6 KiB
www.haskell.org/testimonials/logos/calabrio.png	0.0 ms	8.5 KiB
i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg	7200.0 s	10.9 KiB
www.haskell.org/js/bootstrap.min.js	0.0 ms	7.8 KiB
i1.ytimg.com/vi/WHVMjMIJnB4/mqdefault.jpg	7200.0 s	10.0 KiB
www.haskell.org/js/jquery.console.js	0.0 ms	7.2 KiB
www.haskell.org/js/tryhaskell.pages.js	0.0 ms	6.8 KiB
www.haskell.org/testimonials/logos/scarf.png	0.0 ms	5.9 KiB
www.haskell.org/testimonials/logos/bitnomial.png	0.0 ms	4.1 KiB
www.haskell.org/testimonials/logos/serokell.png	0.0 ms	3.6 KiB
www.haskell.org/js/tryhaskell.js	0.0 ms	2.8 KiB
www.haskell.org/img/haskell-logo.svg	0.0 ms	1.6 KiB
www.haskell.org/js/home.js	0.0 ms	777 B
www.haskell.org/css/fonts.css	0.0 ms	410 B
cdn.jsdelivr.net/npm/glider-js@1/glider.min.js	604800.0 s	3.2 KiB
cdn.jsdelivr.net/npm/glider-js@1/glider.min.css	604800.0 s	1.1 KiB

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

	URL	Resource Size	Est Savings
Sponsors Fastly's Next Generation CDN provides low latency access for all of H… `body.page-home > div.wrap > div.sponsors`	www.haskell.org/img/pattern.png	291.1 KiB	41.1 KiB
Mercury: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/mercury.png	25.3 KiB	23.7 KiB
Bellroy: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/bellroy.png	23.2 KiB	21.5 KiB
Scrive: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/Scrive.png	19.3 KiB	17.6 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/t1e8gqXLbsU/mqdefault.jpg	19.7 KiB	17.5 KiB
Stack Builders: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/stackbuilders.png	18.4 KiB	16.8 KiB
HubSpot: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hubspot.png	16.1 KiB	14.5 KiB
Fission: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/fission.png	15.2 KiB	13.6 KiB
Hasura: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hasura.png	14.4 KiB	12.8 KiB
e-bot7: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/e-bot7.png	14.2 KiB	12.6 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/LnX3B9oaKzw/mqdefault.jpg	14.0 KiB	11.8 KiB
Foxhound Systems: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/foxhoundsystems.png	13.2 KiB	11.7 KiB
finn.no: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/finn.png	12.6 KiB	11.2 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/4RuLzL_q0zs/mqdefault.jpg	13.3 KiB	11.1 KiB
IOHK: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/iohk.png	11.0 KiB	9.8 KiB
NoRedInk: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/noredink.png	10.8 KiB	9.6 KiB
CentralApp: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/centralapp.png	10.2 KiB	9.1 KiB
Imagine AI: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/imagineai.png	9.4 KiB	8.4 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg	10.5 KiB	8.3 KiB
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/WHVMjMIJnB4/mqdefault.jpg	10.0 KiB	7.8 KiB
Calabrio: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/calabrio.png	8.3 KiB	7.4 KiB
Scarf: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/scarf.png	5.7 KiB	5.1 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

lhId: page-22-DIV

nodeLabel: Try it! Type Haskell expressions in here. λ Got 5 minutes? Type help to sta…

path: 1,HTML,2,BODY,1,DIV,11,DIV

selector: body.page-home > div.wrap > div.pattern-bg

snippet: <div class="pattern-bg">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

title: Preconnected origins

value: no origins were preconnected

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

value: No additional origins are good candidates for preconnecting

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

URL	Transfer Size	Duration
www.haskell.org/css/hl.css	17.0 KiB	131 ms
www.haskell.org/css/fonts.css	410 B
cdn.jsdelivr.net/npm/glider-js@1/glider.min.js	3.2 KiB
cdn.jsdelivr.net/npm/glider-js@1/glider.min.css	1.1 KiB	201 ms

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Estimated savings: 120 ms 14.9 KiB

URL	Transfer Size	Est Savings
www.haskell.org/css/hl.css	16.8 KiB	14.9 KiB

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Estimated savings: 0.0 ms 4.1 KiB

URL	Transfer Size	Est Savings
www.haskell.org/js/jquery.console.js	7.0 KiB	4.1 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

	URL
Calabrio: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/calabrio.png
Mercury: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/mercury.png
Hasura: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hasura.png
NoRedInk: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/noredink.png
Scarf: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/scarf.png
CentralApp: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/centralapp.png
Imagine AI: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/imagineai.png
IOHK: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/iohk.png
Bitnomial: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/bitnomial.png
Foxhound Systems: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/foxhoundsystems.png
Serokell: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/serokell.png
e-bot7: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/e-bot7.png
finn.no: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/finn.png
Scrive: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/Scrive.png
Stack Builders: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/stackbuilders.png
HubSpot: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/hubspot.png
Fission: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/fission.png
Bellroy: Logo `div.span3 > div.thumbnail > a > img.img`	www.haskell.org/testimonials/logos/bellroy.png
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/re96UgMk6GQ/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/LnX3B9oaKzw/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/4RuLzL_q0zs/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/t1e8gqXLbsU/mqdefault.jpg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/WHVMjMIJnB4/mqdefault.jpg
Haskell `div.row > div.span6 > div.branding > img.img-responsive`	www.haskell.org/img/haskell-logo.svg
div.row > div.span3 > a.thumbnail > img.img-responsive `div.row > div.span3 > a.thumbnail > img.img-responsive`	i1.ytimg.com/vi/IzQTfh-Iuds/mqdefault.jpg

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Time to Interactive 1.6 s

●Layout shift culprits

●Document request latency

●Optimize DOM size

●Font display

●Forced reflow

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Max Potential First Input Delay 20 ms

●Minify CSS

●Reduce unused JavaScript

●Avoids enormous network payloads Total size was 858 KiB

●JavaScript execution time 0.0 s

●Minimizes main-thread work 0.2 s

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 90 ms

●Server Backend Latencies 170 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Avoid multiple page redirects

●Initial server response time was short Root document took 90 ms

●Avoid large layout shifts 3 layout shifts found

○INP breakdown

○User Timing marks and measures

○Avoid long main-thread tasks

○Avoid non-composited animations

Accessibility

Contrast

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

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

These are opportunities to improve the legibility of your content.

Navigation

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.

Names and labels

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

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.

Best practices

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

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

●Buttons have an accessible name

●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

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●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

○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.

Best Practices

General

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Source	Description
i1.ytimg.com/vi/IzQTfh-Iuds/mqdefault.jpg	`Failed to load resource: the server responded with a status of 404 ()`

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Use a strong HSTS policy

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

100

SEO

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`

Browse & Analyze

Learn

Results for https://www.haskell.org

Site Health

Top Priorities (5)

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Names and labels

Contrast

Navigation

Best practices

Best Practices

General

SEO

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Contrast

Navigation

Names and labels

Best practices

Best Practices

General

SEO

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