Thanks to the on-demand economy—a term so sweeping it’s become almost meaningless—you can summon a massage, a dog walker, a Starbucks latte, a handle of whiskey, or legal advice with a few taps on your phone. A new crop of startups wants to make it just as easy for businesses to find temporary workers.

These “on-demand labor” startups, which offer more automated, efficient versions of traditional staffing agencies, say that they are adding more jobs to a well-established part of the labor economy. “We’re not saying, replace 100 workers [with our app],” says A.J. Brustein, the CEO of an on-demand staffing platform called Wonolo. “There is no way a Wonoloer is going to come in on the first day and be as productive as someone who has been working there for three years. In our mind, our platform has tens of thousands of jobs that wouldn’t have existed before.” Others, like Susan Houseman, a labor economist at the Upjohn Institute, have suggested that companies’ increasing ability to expand workforces to cover peak times and then downsize them when there’s less work–a trend that has been around for a while–is cutting into the supply of dependable work and income.

The number of workers employed through temp agencies is already at a record high. However you feel about the impact of this kind of work, on-demand labor could push that number even higher.

The largest startup in the still nascent on-demand labor space, Wonolo (the name is a take on “work now locally”), is backed by Coca-Cola and has several hundred businesses signed up as clients. It sets up temp work in the same way that companies like Uber and Handy broker rides and cleaning appointments: Its app pushes short-term jobs like event staffing and warehouse work to potential temp workers via a smartphone app. Workers, who are not classified as employees, but as independent contractors, can choose to accept them or reject them whenever they want.

Most traditional staffing agencies hire their workers as employees (some exceptions have faced lawsuits alleging they misclassified workers as independent contractors). Independent contractors have no right to minimum wage, overtime pay, unemployment insurance, benefits like health insurance, or collective bargaining. Consequently, they cost about 30% less to hire.

Brustein says that part of what makes this classification appropriate is that Wonolo fills a different niche than a traditional staffing agency. “What staffing is great for is helping you deal with predictable work,” he says. “You know you’ll need people over Christmas? Temp staffing is great. Have someone going on maternal leave? Temp staffing is great. Temp staffing generally can’t help you if seven people call in sick with a cold.” Richard Wahlquist, the president and CEO of the American Staffing Association, says temp agencies usually handle jobs with a longer lead time than a day. “Tomorrow is tough,” he says. “Next week is easier. I would say that it would be good to expect at least five days.”

Another startup called BlueCrew has the same quick-employment goals as Wonolo, but it hires its temp workers as W2 employees. W2 jobs are not necessarily better than 1099 jobs (see just-in-time scheduling), but the company pays into Social Security, Medicare, workers’ compensation, and unemployment insurance on workers’ behalf, and, if BlueCrew workers hit full-time hours, helps pay for their health benefits. Like Wonolo workers, they can still choose to accept or reject jobs offered to them via an app.