Mr. Carroll brags that Leap2 has been able to spend “almost 100 percent” of its budget on programming talent. That spending goes further because Leap2’s developers, as independent contractors, do not get benefits.

Most of Leap2’s developers have staff jobs at bigger, established companies that provide health insurance. Because most of them have children, they tend to do their work for Leap2 after about 9 p.m. Only one contractor, Travis Williams, does not have a day job anywhere. He is a graphic designer who juggles multiple projects by choice, and he has health insurance through his wife, who is a kindergarten teacher.

Though the company’s developers are mostly local, they interact primarily by instant message or Skype. They meet in person once a week over dinner, and one, Michael Marley, who works on contract through the Allen Group in Norwalk, Conn., calls in via Skype. A monitor showing his face is propped up on a chair to suggest he is in the room.

“You used to hear about inventors tinkering in their garage,” said Tyler VanWinkle, the company’s product manager. “Skype is the new garage.”

This focus on leanness and streamlining is not limited to high-tech start-ups, according to Eric Ries, the author of “The Lean Startup.” He said the revolution began in Japan in the 1980s, when manufacturers learned the value of creating products in smaller batches and refining them more often, and has since spread.

“Now you can rent the means of production instead of owning them,” he said.

All of these factors should make it easier to start a business, suggesting that the volume of new companies would help make up for the smaller head count at start-ups. That has not been the case in recent years, however.

Over the last five years, the number of new employer businesses, including new franchises for existing companies, fell by 20 percent, to 536,445 in 2011 from 667,341 in 2006.