Sean Conaty looked closely at a favorite plaid shirt. He counted threads, noted their colors and followed their directions. Then he tried drawing the pattern in Microsoft Paint, one pixel at a time. A garment had become a programming problem, although the programming would have to wait. First came the decidedly unglamorous business of copying and pasting.
A shirt is a useful place to begin this story. Plaid has an appearance of complexity: intersecting stripes, changes of color, the little visual negotiations where one direction crosses another. Yet it repeats. Find the unit and understand the rules, and a large surface becomes something a computer can reproduce. Conaty wanted to make that process less laborious.
The result was PlaidMaker, his online pattern-making tool. Alongside a career in software engineering, he has kept a project devoted to a very particular creative task. Its origin is pleasingly literal. Someone examined the thing in front of him, tried making it by hand, and decided the computer should take a turn.
The shirt gets a second life
Paint gave way to Photoshop, where layers, masks and repeating patterns made the work more efficient. Conaty still wanted to write a program. The missing piece was image creation: he knew what he wanted the algorithm to do, but needed the means to draw its output. Learning PHP and the GD graphics library supplied those means.
PlaidMaker dates to September 2008. Today, the site offers a maker and a gallery of saved designs. A visitor can create a pattern, download it or save it publicly. PlaidMaker Plus adds private storage for designers who want their work accessible only to themselves. The distinction is small but practical: sometimes a design is ready for company, and sometimes it needs a room of its own.
A digital pattern need not remain digital. In 2016, designer Su Schaefer credited Conaty's software for the plaid component of an orange, black and white design photographed as a printed fabric swatch. The finished work included her own line art and textures. It offers a concrete example of the tool entering somebody else's creative process, then emerging as something you could touch.
That is a satisfying route for a small piece of software: from an object to an image, through another person's choices, and back to fabric. It also leaves the authorship where it belongs. The designer makes the design. The tool helps her do it. A good pair of scissors has never needed its name sewn into the hem.
- 01Look closelyThreads, colors, directions
- 02Draw by handMicrosoft Paint pixels
- 03Repeat smarterPhotoshop layers and masks
- 04Write the toolPHP and GD image creation
A day job, and a project of his own
Conaty is based in Portland, Oregon, and works as a senior full stack engineer at Judi Health. His professional history includes interface design and development at AdBrite, front-end work at Potrero Media, and software engineering at Hearsay Systems. Later came Atlassian and Scrunch AI. PlaidMaker runs alongside that employment history, carrying its own September 2008 starting point.
The Atlassian stretch began in April 2017; the senior software engineer title followed in September 2019. His next engineering role, at Scrunch AI, ran from July 2024 to May 2025. He joined Capital Rx in May 2025; today, his role is at Judi Health. These are changes of workplace around an unusually durable independent project.
He attended the University of California San Diego from 2000 to 2004. His university activities included ultimate disc. There is no need to turn the sport into an elaborate theory of teamwork; it is an ordinary detail in a career otherwise described by employers, programming languages and job titles. People have afternoons as well as résumés.
A colleague from Remind, Sean McQuillan, describes Conaty's attention to system design and his feel for product design. Gidon Wise recommends his design work too. Those accounts place him at the meeting point between how an application is put together and what using it feels like. Both questions are present in a pattern maker: can it produce the image, and can somebody make the image they intended?
Roses are red, after the edit
Conaty's writing about code has room for a joke. In an April 2012 explanation of Git commits, he builds a short poem in stages, gives the roses the wrong color, then corrects them. The subject is how to combine changes into a readable history. The literary achievement is modest. Its usefulness as an example is considerably greater.
Git records changes to files. During development, that record can accumulate false starts and corrections. Conaty demonstrates interactive rebasing, arranging a correction beside the earlier change and combining them. The final history becomes easier to follow. The point of his example is the organization of work for the person who will review it later.
There is an enjoyable admission in the setup: immaculate-looking code can have a decidedly untidy first draft. Most readers will recognize the condition even if they have never opened a terminal. A finished paragraph rarely preserves every sentence its author tried. A useful revision history likewise needs some editorial judgment about what belongs together.
The poem makes a dry procedure memorable without requiring a grand anecdote about a late-night production emergency. A mistaken rose is enough. It is a little teaching device with a clear sequence: attempt, correction, reorganization. For readers learning the operation, the joke and the explanation arrive in the same package.
The browser has opinions about poetry
A few days later, in May 2012, he published a lesson about whitespace in HTML. The example this time was Edgar Allan Poe's Lenore. Text that appeared carefully arranged in a file became a continuous passage in the browser. Adding line breaks restored the lines, but the indentation still disappeared. Preformatted text supplied the remaining piece.
The subject is how ordinary HTML collapses spaces and line breaks. For someone arranging words on a page, that behavior can feel like a very fussy printer taking unauthorized liberties. Conaty moves from the poem to a more technical consequence: extra spaces between elements can change the appearance of syntax highlighting. Something almost invisible in the file becomes visible in the result.
It is a lesson about checking the thing people actually see. A document can look orderly to its author and behave differently when rendered. That gap is familiar beyond software. The editor, the designer and the engineer all eventually have to look at the finished page. The browser, regrettably, cannot be persuaded by how nicely the draft was arranged.
Placed beside the plaid project, the essay suggests a useful connection between his subjects. Both involve translating a structure into an image on a screen. Repetition matters in one; spacing matters in the other. The dimensions are tiny, but the consequences are right there in the picture. Paying attention changes what the viewer gets.
When a string crosses a boundary
His July 2014 essay, Escape From HyperText, takes up another translation problem: strings moving between HTML and JavaScript. It distinguishes the contexts in which text is interpreted and explains how an apparently ordinary value can be read as part of the page's structure. The examples concern escaping, templates and the handling of content supplied by users.
Here, his tone becomes more insistent. He describes a shared utility intended to handle a recurring case and mentions a colleague's pre-commit hook that checks a template convention. These are ways of reducing the amount a developer has to remember unaided. A rule written in a document is helpful; a check built into the workflow can catch an oversight before it travels farther.
The essay is tied to the tools and conventions of its moment. As a piece of professional writing, its interest is the route through a difficult subject: separate the cases, show the consequence, explain the safeguard. It exposes the work beneath the interface. Even a plain field of text has crossed several boundaries before it appears where a user expects it.
“building a tool that lets others be creative too”
Sean Conaty, on PlaidMaker
Leaving room for somebody else's idea
Conaty describes the appeal of his own creative work in terms of “building a tool that lets others be creative too.” It is a compact statement of purpose. PlaidMaker gives it a visible form: a set of controls, a repeating image, and the freedom to choose colors that its maker would never have chosen himself.
His interests also extend to looking at other people's visual collections. In a December 2024 discussion, he mentioned enjoying David Rumsey's map collection while responding to a site devoted to old maps. The comment is brief, but specific. Patterns and maps both reward looking closely; neither requires a person to hurry past the details.
The shirt remains a good closing image because it carries the whole sequence without decoration. Look, try, revise, build. The resulting program belongs to Conaty. What somebody makes with it belongs to them. Somewhere along that route, counting threads became a way to hand another person a blank piece of fabric.