In 2007, Mark Zuckerberg, then 22, said out loud what many in the software industry think: “Young people are just smarter.” Twelve years later, the lack of older programmers is still little studied compared to other dimensions of diversity. Google’s annual diversity report, for example, counts how many women or people of color it employs. Microsoft tallies its American Indian and Alaskan Native staff, and Apple is proud to hire veterans. It is commendable that these companies have revealed some measures of their diversity, but there is an omission: None report their age distribution.

Ari Rapkin Blenkhorn is a 47-year-old engineer who says she quit her last full-time job because the company, she says, wanted “a crowd of cheap youngsters. They didn’t want to support more senior people with established careers.” Her employer, which she requested not be named, valued her professional connections but did not invest in that network by sending her to conferences. “I believe they really didn’t understand why this was important or how my attending a research conference was different from junior developers attending technical training.”

Blenkhorn says that once she was back on the job market, the ageism she experienced was compounded by sexism. Despite her profound technical achievements, she was dismissed by recruiters as irrelevant and dull, as a “mom.” She recently completed a PhD in computer science and hopes the education will improve her chances in the job market.

Kevin Stevens, a 55-year-old programmer, faced a similar attitude when he applied for a position at Stack Exchange six years ago. He was interviewed by a younger engineer who told him, “I’m always surprised when older programmers keep up on technology.” Stevens was rejected for the job. He now works as a programmer at a hospitality company where he says his age is not an issue.

For other programmers, the outcomes can be far worse. A 2018 investigation by ProPublica’s Peter Gosselin and Ariana Tobin into age discrimination at IBM found that starting around 2014, the company attempted to reinvent itself by replacing older workers with younger ones. It laid off veteran employees by the thousands and strong-armed others into retiring. One 60-year-old systems engineer named Ed Kishkill was sent a layoff notice and told he had three months to find another job at IBM. Despite his decades of experience, he was rejected for all other positions. By the time of the ProPublica article’s publication, Kishkill was working as a Staples store clerk.