Treehouse founder and CEO Ryan Carson believes that making the process of learning to program more gamelike is “tremendously powerful” because it makes learning addictive—something he says he’s heard from customers. “Obviously that would be terrible if we were selling tobacco, but we’re not,” he says. “We’re selling making yourself better.”

And people are buying into it. So far, the site has 8,000 paid users, most of whom it picked up since rebranding under the Treehouse name in November (before that, it was operating as a companion to a site Carson runs for Web designers and developers called Think Vitamin). Treehouse charges a monthly fee of $25 or $49, depending on the desired detail of instruction (for students, it costs $9 per month).

Carson doesn’t think avid subscribers will have to pay much to learn to code, though. He expects that in about six months, a user could get enough training to build a simple Web application, and after a year, he says, a user could get an entry-level coding job. “And you could do that the whole time living out of Pueblo, Colorado,” he says.

It’s still too early to tell if this will happen, though—Treehouse is still working on its curriculum, so it won’t be finished creating the most advanced lessons until September.

Gabe Zichermann, who runs an annual conference called the Gamification Summit—focused on adding gamelike functionality to all sorts of activities, in order to increase engagement— says that while these startups don’t include typical video-game tropes like throwing bombs or killing Orcs, they are creating a positive experience that takes users’ minds off the fact that they’re learning something new and difficult. “They’re unpacking that and making it significantly more engaging,” he says.

Codecademy and Treehouse can be useful to those who already know how to code, too. Amanda Rae Arseneau, a programming student in Toronto, signed up for Code Year in January and has been following along faithfully each week.

Arseneau, 32, says the program is helping her learn new skills and refresh old ones. And unlike with her three-year-long vocational school program, she says, completing a Code School lesson gives a sense of immediate gratification, and game-related tasks like building a blackjack game are fun.

“It’s much more engaging than a textbook,” she says.