I queried my network, asking if anyone else had been given homework assignments. It turns out I wasn’t alone. Developers all over the U.S. had encountered the practice, spending anywhere from a few hours to over three days working on their unpaid interview assignments. In a talk given at PyCon last year, software developer Susan Tan said she spent as long as 32 hours on homework, only to be rejected because it was missing a feature not even stated in the original requirements.

Holiday’s company now uses a structured “live-coding interview” format that involves reviewing code together and talking about it. The process typically takes between 30 minutes to an hour.

Alistair Davidson, a Technical Architect in London, says his company made the same switch after learning that a “small” homework assignment they’d developed took a candidate 16 hours to finish. “[A live-coding interview] gives you a better feel for what it’s like to work directly with someone and try to solve a problem with them” he says.

https://work.qz.com/1254663/job-interviews-for-programmers-now-often-come-with-days-of-unpaid-homework/