That's a great topic!
Back in 2017, I decided to work for a small student non-profit (~100 members) I had been the treasurer of for more than a year — so obviously the mission did resonate with me because I was a member and co-lead of the organisation in the first place.
They didn't actually ask me anything: I volunteered to build them a new website. The motivation for me was to gain some experience, both with code and project management.
At the time being paid was out of the question, because I was doing it as a fellow student, and I did not have the experience to demand anything. Besides, I had much more time to give away than I do now. :)
So if the situation came up again, and I really connect with the mission, I'd say it depends on the size of the project:
I'm interested in seeing what others think!
It's cool that you help for free by offering, they generally need it. 👍
This is a good balance (some small work for free, paid on bigger projects) if you are actually trying to help.
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