If you wanted to contribute to an open source game, what benefit would this have on your resume or portfolio? If you are trying to build up your portfolio or resume, should you pursue open source contribution, or should you just work on things like your own game demos or something else?

I've been discussing this recently with several industry contacts and it seems that visible contributions to a project on GitHub - yours or someone else's - are worth quite a lot nowadays. Potentially more than having "polished demos" of your own as people seem to care less about the fit and finish these days. The nice thing about seeing code work on those sites is it's a glimpse of how your actual workflow looks, which is actually job-relevant. Even if it's your own portfolio demo, it should be open source with the development process visible.

Mind you, this is my anecdotal experience. But when I'm asking people what they want to see in junior candidates, I'm not hearing "demos" anymore. I'm hearing "internships" and "open source work".

I'm hoping open source contributions are valuable because it's all I've done over the last 17 years or more, and I'm looking for work right now.

It seems it's irrelevant for a lot of lazy silicon-valley types who follow the Google lead and insist on timed online tests of how well you can solve random mathematical problems in 20 minutes that took academics years to solve when I was in university. If any place demands you take such a test, don't take them to the next level because if they can't be bothered to make a legitimate effort during hiring, they're not going to make a legitimate effort during employment either. I'm a former hiring manager, I can see through their shit.

Open source is your code portfolio. You should aim for both the old and new way: create a portfolio of your work and keep the sources open on github or the equivalent.

For me, I would want to see actual code from you when applying, but I don't care if it's open source or not. Being able to contribute to open source projects is not something everybody is equally suited for, so I don't like to place too much weight on it. It does demonstrate some degree of teamwork and version control competence though, so for anyone without open source contributions, they might want to think about how they can show those skills in other ways.

I will always value one who contributes to open source more than who doesn't, for 3 skills:

the first is the ability to face negative feedback by showing public code are asking for pull requests and communicating with people you don't know...online.

the second thing is the ability to find areas of improvement in public codebases. a lot of tools used at work are open source and the ability to find flaws, bugs and not-yet implemented features in them is crucial. it means the candidate will apply those skills also in internal projects.

and lastly giving something back. as i said before, a lot of the tools and instruments and frameworks used at the workplace in software development are open source. by paying their salaries the employer also indirectly invests in open source, because his engeneers are active consumers of those products. and they're are giving nothing back ? why is that.