University of Waterloo art and business student Jenevieve Ayuste along with University of Toronto computer engineers Faye Feng and Judy Shen developed an app called "WalkSmart" at deltaHacks that would allow a user to alert friends she hadn't made it home within the timeframe she expected to. (Kelly Bennett/CBC)

It served to highlight some stereotypical excesses of a male-dominant tech culture:

A finalist entry at a college hack-a-thon event in California last year developed an algorithm to estimate how likely a woman would be to sleep with the user of an app called Wingman, based on how much skin she showed in her profile photo on Tinder, whether or not she attended a "party school" and other factors.

At a hack-a-thon called "deltaHacks" this weekend at McMaster University, the bottom line looked dramatically different.

The event Saturday and Sunday invoked the mathematical definition of "delta" as "change." The 300 or so college programmers and designers who participated in the 24-hour intense, project-based event were coming up with projects to "hack for change." They used software, hardware and sometimes both to bring ideas to fruition in time for Sunday's expo and judging sessions.

Consider the project by Jenevieve Ayuste, Faye Feng and Judy Shen:

The WalkSmart app would allow a user to push an easy "HELP" button to send texts to a preset list of emergency contacts. (Kelly Bennett/CBC) A user would use simple buttons on their app, WalkSmart, to alert friends she felt unsafe when she was walking somewhere alone, or that she hadn't arrived home within the timeframe she expected to.

With more than the 24 hours allotted for this project, the team would hope to add functions like GPS tracking to the app.

"This hack-a-thon was about social impact; that's what drew me to it," said Shen, who studies computer engineering at University of Toronto.

"Most of the hack-a-thons are about 'How will this app make money?'" added Feng, Shen's classmate at U of T.

A group of McMaster computer software and engineering students had a very different idea, also with a social component.

Jamie Counsell grew up in a small town where he remembers everyone buying each other's Tim Hortons regularly. Counsell and classmates Rakesh Mistry and Shawn Simon created a location-based pinnable map where users could announce when they've done a good deed like rescue a lost pet or buy someone's coffee.

An app called 'Deeds' developed at this weekend's hack-a-thon at McMaster University would encourage users to do good deeds, pin the location where they did them, and pay others' deeds forward. (Kelly Bennett/CBC) It's up to other users to pay that good deed forward — exponentially. A red pin doesn't show up as "paid forward" until two more good deeds are logged in response.

The hack-a-thon helped populate the map right around McMaster as hackers bought each other coffeee Sunday. Some teams looked a little bleary-eyed Sunday afternoon after sleeping for just a couple of hours between working on their idea.

'This shows what students can do'

Some of the challenges carried prize incentives like medals, tablets, subscriptions to tech services and a paid summer internship at Geographers Without Borders.

Justin Hall is a master's student in McMaster's geography department. Together with Ph.D student Charles Burke, he's launched a concept called Start the Cycle, a bike-sharing library for kids. The startup needed a lot of coding help to get its geographical tracking, online sign-up and back-end logistics database connected. So Hall and Burke asked for a team to address their gaps as part of the weekend.

"We couldn't do it on our own," Hall said. "We'd have to get it done somehow, and this way we get skilled coders involved."

Mohamed Fouda, member of HackitMac, the group sponsoring deltaHacks, said that emphasizes one of the event's main goals: To give students real-world coding experience they can include in a portfolio.

"If you Google my name right now, you're not going to find much, but if I worked on a hack-a-thon..." he said. "This shows what students can do."