Want to learn to code without paying up front? Programs such as Lambda School, App Academy and even Purdue University are experimenting with income-share agreements (ISAs), in which students agree to pay a portion of their income after graduation, reports The Atlantic. It’s a promising idea, particularly when businesses need to fill over half a million computer-science jobs. But the schemes are still in their infancy, and it remains to be seen whether ISAs prove to be a viable business model or successful for graduates.