Redesigning a news site is simple — that is, until you add in the content, ads, in-house promotions, comments, departmental politics, and performance issues.

There’s been no shortage of attempts to re-imagine The New York Times site, whose design dates back to 2006. The latest offering is a little different from the others, though: Michael Donohoe, a Seattle-based developer who recently left the Times after seven years there, has built a Google Chrome extension that dynamically re-skins the Times’ website. It’s called Ochs, as in Arthur, and it uses CSS and JavaScript to create a sort of living mockup, powered by real content.

It’s an uncluttered, iPad-inspired look (a lot like the Times’ newish Opinion Pages). Headlines and body text are set in Cheltenham, the Times’ serif of choice since 2003, instead of plain-vanilla Georgia.

Donohoe tells me he is not trying to Fix The New York Times; he’s scratching a longtime itch. While at the Times, there were parts of the site that pleased no one, he says, but never got fixed. “For example, that left navigation on the homepage. People generally know that as an eyesore. People don’t actually click on it. People don’t use it,” he told me. “They recognize that there’s a problem, but they can’t figure out what the solution is — or they can’t find a consensus on a solution that would work.”

It’s a problem for any large news site, not unique to the Times: how to reinvent a complex, heavily trafficked news environment while keeping the whole thing running smoothly. Donohoe said he built his design for the user he knows best: himself. “There are things that I got rid of or things I didn’t like” — Today’s Paper, for example, or the Video vertical. (“People don’t click on that, either,” he added. “I can’t recall a specific internal report that said it, but you could kind of hear people talking about it in the background.”)

He also cut out a lot of the ads, which is the most common bit of criticism he receives about Ochs. On the NYTimes.com homepage today, I count 12 display ads, seven of them in-house ads. On Donohoe’s version of the same page, I count one.

The ads are absent for technical reasons, he said, because he’s trying to figure out how to preserve them without breaking his layout. Eventually, “my goal is to restore as many ads possible.”

While he’s at it, though, Donohoe is thinking out loud about improving the ad experience. He is resurrecting some ideas from the very early Times redesign days, back in 2005, the no-such-thing-is-a-bad-idea days. One idea is what he calls “progressive advertising” (or perhaps regressive advertising), wherein a user sees fewer and fewer ads the longer he navigates the site. And then there’s the idea of hiding ads for paying subscribers, which the Times rejected early on.

“There are definitely people who thought, ‘Well, I paid for the Times, I shouldn’t see adverts.’ I’m in that camp, personally,” Donohoe said. Then again: “You could argue that people are willing to pay for the Times, so they are a more and more valuable audience for the Times” (and its advertisers).

The user base for Ochs is small — 240 a week, according to the Chrome store, a fraction of a fraction of one percent of the Times’ audience. “If this had 100,000 users tomorrow, I’d say, ‘Well that’s crazy,’ and that would be affecting The New York Times’ bottom line.” And from the Times itself — or, at any rate, Donohoe’s former colleagues at the Times — he’s received only positive feedback, Donohoe said, save for a little concern that it’s an attempt to skirt the paywall. (It’s not.)

“Not to sound selfish, but I’m kind of doing it for myself,” Donohoe said. “I just use this as a mental exercise when I need a break from my other work. It’s…a work in progress. I’ll spend an hour on a Thursday night just padding pixels.” Ochs is a labor of love, he stresses, not an attempt to “initiate reform.”

See the current NYTimes.com home page and the Ochs version below: