My name is Mat “Wilto” Marquis, and I make websites.

I’m an independent consultant. My specialization is inclusive web development.

My goal is to ensure that your content can reach any user, in any browsing context—regardless of the size of their screen, the speed of their internet connection, the age of their device, or the combination of browsers and assistive technologies they use to experience the web.

If you have the same goal, we should chat.

I’ve helped build some websites.

I’m a developer that heavily skews “designer.” From design to implementation, I believe that a good layout is a flexible, durable, and maintainable one.

I’ve been brought in to help clients like Rolling Stone with their performance concerns, clients like Axios and Microsoft with their accessibility concerns, and clients like ProPublica and Amazon’s PillPack to build, maintain, and improve on their websites.

Responsive Web Design

I’m incredibly fortunate to have played a small part in the history of Responsive Web Design, from the earliest discussions of the responsive Boston Globe project—all the way back in 2011—to leading the effort to add responsive image features to the HTML specification, browsers, and major CMSes.

Front-End Performance

I’ve had the privilege of traveling the world speaking about front-end performance. I’ve worked with organizations large and small not just to audit, identify, and help fix their performance pain points, but to establish workflows, development habits, and support systems that allow those improvements—and their results—to persist long after I’m gone.


I firmly believe that accessibility isn’t an add-on, a line item, or an ticket languishing in an issue tracker for “if we have time at the end.” It’s a persistent consideration through every step in the creation of a site—from content, to wireframes, to markup, to the final product. In the years that followed my accessibility work on the jQuery UI and jQuery Mobile teams, I’ve helped guide a number of organizations through the process of prioritizing accessibility both technically and culturally.

The homepage. An article page on The homepage. Homepage of a component library for an unspecified client.

I’ve written a few good books, and tech edited some great ones.

Cover of JavaScript for Web Designers. Cover of Image Performance

JavaScript for Web Designers is paced for anyone taking their first steps into the world of JavaScript development, but in-depth enough for anyone looking to understand JavaScript’s inner workings. Image Performance is a deep-dive into a subject that’s easy to take for granted, but difficult to master: putting images on the web. It covers everything from the inner workings of image formats and compression methods to responsive image markup to automation.

After (“despite?”) working with me twice as an author, A Book Apart brought me on board as their in-house Technical Editor.

Before writing any books of my own, I wrote the Robust, Responsible, Responsive Web Design chapter of Smashing Book 4, and two chapters on JavaScript for the fourth edition of Jennifer Robbins’ Learning Web Design.

And if any cookbook publishers come callin’, well, I’ll hear them out.

I want to build a better web.

Me, I’m stubborn. If it can be done on the web, I believe that it can be done responsively, it can be done accessibly, and it can be done in a performant way—it can be made to work for everyone.

The trickier that might seem at first, the more you’ve got my attention.

Those are the kind of projects I’m interested in—not just because that’s the sort of impact I want to make on the web, but because that’s where the exciting work is. That’s the space where we get to invent new approaches and techniques; to build something brand new together, in pursuit of making the web a faster, more welcoming, and more inclusive place.

If it sounds as though I might be a good fit for your next project, don’t hesitate to get in touch. I’m looking forward to it.

We’re all in this together.

If you’re here to help people, I’m here to help you.

I’m immensely proud to have volunteered time to organizations like Blaseball Cares (claws up) and The Covid Tracking Project—groups working to make a real difference in peoples’ lives.

If your organization is working to help those in vulnerable positions and you think my areas of expertise could help you do just that, let’s talk.

Whether it’s an on-the-fly accessibility audit, tips for speeding up your website, a second opinion on a particularly thorny browser issue, or any advice about the web, how it’s built, and how to hire the people that build it: your non-profit is welcome to book some “Office Hours” time on my calendar, completely free of charge, whenever it’s convenient for you and your team.

I keep busy.

I’m a former amateur boxer, decent cook, passable carpenter, bumbling antique British motorcycle mechanic, wannabe botanist, and third-year beekeeper.

I’ve been a speaker at conferences like An Event Apart and Smashing Conference, and an emcee for Confab. I’ve even been in a movie—What Comes Next is the Future—to discuss the role I played in web standards, and how I hoped to change them. I’ve got an IMDB page and everything!

Just—… just ignore the other thing on there.

It’s a long story.