With age and experience comes wisdom, or so the saying goes, but when it comes to being a developer is it a job you can pursue into middle age?
There are plenty of stats and anecdotes that suggest the average age of developers skews young.
Norman Matloff, professor of computer science at the University of California, has long argued there is an upper age limit on the profession, writing that "statistics show that most software developers are out of the field by age 40". Just last year, an ageism lawsuit against Google claimed the median age of the firm's employees was 29.
Looking beyond Silicon Valley, recent surveys have also found that developers tend to be younger worldwide. This week, a survey by Stack Overflow found that, on average, developers in London have been coding for just under eight years. Globally, average coding experience is even lower, about six and a half years. The implication that most developers are relatively recent starters chimes with another result from Stack Overflow's global survey of developers, which put the average age of coders at under 30.
"Stack Overflow may not be that representative, but the figures are certainly reality. Younger people are cheaper, with the cutoff being about 35," said Matloff.
Matloff's argument is that once coders reach the age of 35 - 40 they face a greater number of rejections, which he said are usually attributed to them not having kept up with the latest technical skills or, conversely, being overqualified. The more likely reason, he believes, is that experienced developers cost too much money.
It's certainly true that developers' salaries do track higher than the average wage. Across the UK, the average salary of a developer is £51,339 ($75,654), according to Stack Overflow's developer survey, putting developers in the top 20 percent of earners.
However, not everyone agrees that Stack Overflow's findings necessarily back up the argument that older developers are leaving the profession.
Fintan Ryan, analyst with RedMonk, said the Stack Overflow surveys are likely weighted in favor of younger developers that use the site.
"There will be an inherent bias in a survey run on a platform such as Stack Overflow towards younger respondents. There are significant groups of older developers in areas such as finance that are not inclined to respond to surveys likes this," he said.
Natalia Radcliffe-Brine, marketing manager at Stack Overflow, is inclined to view the figures as evidence that more young people are entering the profession than ever before.
"I don't think it's that the older developers aren't there anymore, I think there's been momentum around technology and you've got so many more young people going into computer science."
In the UK there are signs of burgeoning growth, both in jobs in the wider tech industry and in the numbers studying computer science. Following the 2008 global crash, the rate of job creation at UK technology companies was found to be far outstripping that within the wider private sector, and Cambridge University recently saw the number of people applying to study computer science pass the high watermark of late 90s dotcom boom.
"The proportion is changing, so instead of having lots of older people in the industry, you have so many more young people coming into it now," she said.
"That's why the age looks a lot younger. I definitely don't think it's that the older developers aren't there."
Nick Heath is chief reporter for TechRepublic. He writes about the technology that IT decision makers need to know about, and the latest happenings in the European tech scene.