Who You Are Building For

Ten years ago I started sharing a desk with Samir, a backend developer who is blind and uses the NVDA screen reader. In his first week he tried to book a train ticket on a well-known site. He got as far as the seat map, a grid of clickable boxes that his screen reader announced as nothing at all, and gave up. He phoned the call centre and paid a booking fee for the privilege. That site’s developers were not careless people. They had never watched anyone like Samir use it.

This course is about closing that gap, with code. You won’t learn a list of rules to recite; you will learn how disabled people actually operate a web page, and the specific HTML, CSS, JavaScript and ARIA that make your pages work for them.

Who you are building for

The World Health Organization estimates that about 1.3 billion people, around one in six, live with a significant disability. That number alone makes accessibility a mainstream concern, but it undercounts the people who benefit. Disability is often temporary or situational:

• Seeing: blindness, low vision and color blindness, but also a cracked phone screen or glare on a sunny platform.
• Hearing: Deaf and hard-of-hearing users, but also anyone in a loud café or a silent library without headphones.
• Moving: tremor, paralysis or a missing limb, but also a broken wrist, or a parent holding a baby in one arm.
• Understanding and remembering: dyslexia, ADHD, a brain injury, but also exhaustion, stress, or reading in a second language.

When you design for the left column, the people on the right get the benefit for free. Captions were built for Deaf viewers; today a large share of social video is watched with the sound off.

The state of the web

Every year WebAIM runs an automated scan of the home pages of the top million websites. The 2026 run found detectable WCAG failures on 95.9% of them, with an average of 56 errors per page. The striking part is how ordinary the errors are. Six categories make up almost all of them: low-contrast text, images without alt text, form inputs without labels, empty links, empty buttons and a missing page language. None of these needs a specialist. Each takes minutes to fix once you know to look.

Notice that every one of them lives in the page’s own markup and styles. That is why this course never reaches for an “accessibility mode” toggle or a third-party overlay script: a second mode drifts out of date, and the default page, the one most disabled people land on, stays broken. You fix the source, and every user gets the fix.

Meet Ticketly

Throughout the course you will audit and repair Ticketly, a single-page booking site for Harbour Lights, a weekend music festival. Ticketly looks fine with a mouse. Under the surface it has all six WebAIM classics, plus a seat picker that only responds to clicks, a “Book now” modal that leaves keyboard focus behind on the page, error messages that appear silently, and an Arabic event title read aloud with an English voice.

Each lesson takes one slice of Ticketly. Section 2 rebuilds its structure with semantic HTML. Section 3 makes it fully keyboard and screen-reader operable. Section 4 fixes what people see and read. Section 5 tests the result with axe, a keyboard, VoiceOver and NVDA, and turns the lessons into habits for a whole team.

Before you change a line of code, though, you need to know what the people using Ticketly are using to reach it. The next lesson looks at assistive technologies and the accessibility tree they read.