That doesn't sound like gaining machine learning experience. It sounds like you are just doing free infrastructure related work for someone else.
It is definitely free work though. There are absolutely ways to get paid to do this sort of thing. But if you believe in learning by volunteering it’s a good option. Having contributions to popular ML repos looks good to tech recruiters as well, so there’s that.
https://devboard.gitsense.com/ggerganov/llama.cpp
The popularity of this project is kind of insane (which probably explains why it was able to raise fairly easily).
If you take a look at
https://reviews.gitsense.com/insights/github?q=merged%3Atrue...
you can see all the merged pull requests (for PRs created within the last 120 days). And if you look at the "gift icon" you can see how long the contributors have been contributing to the project for. For many, it's less than 4 months, which means many new contributors are successfully getting their changes merged.
Edit: Rejected PRs
https://reviews.gitsense.com/insights/github?q=pull-age%3A%3...
Full Disclosure: This is my tool.
I honestly believe we can work smarter and I talk about the paradigm shift here https://devboard.gitsense.com/ggerganov/llama.cpp?board=gits... Note, the repo that is talked about in the intro DevBoard hasn't been pushed yet. DevBoard will be open sourced and I'm currently working on a browser extension (will also be open sourced) that will convert GitHub's insights tab into a hackable dashboard, which should make it easy for people to address GitHub limitations.
hope it can be sustainable/stick around in the future.